Packaging a bike for flying with a bike bag

What??

No!

Hardcase, hardcase, hardcase!!!

Your bike is not going to fare well going most of half way around the world in nothing more than a plastic bag. Please believe me. Don't ruin your tour.

Some shops rent hard cases. Call around and see what you can find. Ask your friends. Ask local clubs. Look for a new or used one, buy it, and sell it when you're done. Ship the empty case to your endpoint.

For that matter, you'll probably be better off- both in terms of how the bike is treated and how much it costs you- if you pack the bike and ship it ahead of time. Just make arrangements with family/friends/local shop to receive it. Get it insured.

Whatever you do, don't ship your bike in a plastic bag. If you don't heed my warning, please post pics.


Yes, it's perfectly safe to use the next larger size tube in a smaller tire. It's a common trick used by bike messengers to reduce the chance of flats. The only downside is a slightly heavier wheel since you're using more tube that you really need.


Raleigh Twenty forks too narrow to accept 93mm hub

How bad is it?  If it's only a couple of mm then just manually spread the fork slightly as you install the wheel.

(Also make sure that no unnecessary washers have been added to the axle.)


Always - Always! Follow the instructions regarding torque - otherwise you could snap your frame/post etc..

As for everything else, I think it's the same, I treat my carbon roadie as I would my aluminium.

Clean it etc, but with carbon, if you have a crash or such, it would be an idea to check for cracks, and get them looked at!


Generally you will find, for getting started a gel seat may help.  As do padded shorts.

However, once you ride regularly, and build some muscle and tolerance around your sit bones, you will find it annoying.

So it is a good gateway drug to getting used to a saddle.  Generally people find that narrower and simpler seats are more comfortable, once you start riding regularly and build up your seat area.


Can a climbing helmet be used for biking safely?

They are designed for different things: climbing helmets have more protection against sharp object penetrating the shell from directly above, while bicycle helmets have more protection for a high force hit with a blunt object (the ground, car bonnets etc) from the sides, front and back.

If helmets are required where you live, unless the climbing helmet meets the standards (EN 1078, CPSC etc) required by your country for cycling helmets, (some might, I don't know) you are not riding legally.

Even the safety benefit of wearing a helmet is hotly debated (refer What are the reasons for and against wearing a bicycle helmet?; wearing the wrong type of helmet is an unproductive debate that will have no useful outcome. Probably what will not be debated too hotly is "If you are in an accident, wearing a climbing helmet is safer than not wearing a helmet" and "It's best to wear a bicycle helmet that meets a recognized standard".

I suggest you refer to discussions in related questions such as are ski helmets safe and Would a military helmet make a safe alternative to a bicycle helmet?.


Front wheel Fork is having scratches and Oil is getting leaked from it?

That stanchion is stuffed and needs to be replaced.  If the damage is from normal wear and tear the other will need replacement - probably cheaper to get a whole new fork. If its accident damage (e.g from rubbing while on a car rack) and the other is in very good condition, replacing the damaged one is an option (if you can find a single replacement).

Replacing the oil will buy you a couple of rides and a mess to clean up at the end of each one, and the shock will not perform particularly well.

Its not really a dangerous problem, but the fork will not be working properly and will sag under load.


How much should a wallet friendly entry level road bike weigh?

A "wallet friendly" entry level bike should weigh as little or as much as your wallet allows.

The key here is entry level. For the vast majority of people in the market for a entry level bike (and most racing cyclists), the weight of the bike is not the limiting factor. All things considered, 8.5kg is not absurdly heavy for a bike, it's actually a shade lighter than my current racing bike, which is more than capable on hilly and flat races.

Bottom line, lightweight and wallet-friendly are usually mutually exclusive when it comes to bikes. Don't worry about the weight, and enjoy the ride.


You have addressed the pinch flat problem by running higher pressure.

If you are getting repeated punctures, even with new tubes, there is probably something still in the tire that is causing the tiny holes.

Finding the offending object can be difficult. I was unfortunate enough to pick up a tiny piece of steel wire (possibly a bit of paper staple) in my rear tire recently that just protruded into the tube. I had to carefully inspect both the inside and outside of the tire to find it.


I would not fibreglass it - instead I'd remove the black coating 10-15mm around the edges of the hole and just over the "curve of the well".

Then I'd use a thin piece of aluminium plate and carefully conform it to the bed of the well.  This would be a lot of careful hammering with a ball-peen hammer and perhaps a cold chisel.  You also want the edges napped or relieved to smooth the transition up and down for the rim tape.  No sharp edges !

Once its all fitting in place snugly, I'd drill the valve stem hole in a pillar drill, and carefully chamfer the edges of the hole.

Weigh the final piece now.

Clean both surfaces and then use a 2 pot epoxy to snot the patch part in place.  Use a bolt temporarily through the valve stem hole to retain it while the epoxy sets, and leave for at least the maximum "hardness" time on the epoxy instructions.

You want to keep it totally below the "terrace" beside the clincher bead hooks, so the repair doesn't interfere with seating of the bead.

Also, you may choose to make a second plate of equal weight to adhere diametrically opposite the valve, to help with balancing the wheel and reduce vibrations at high RPMs.


I think your derailleur needs adjustment.  Watch this video

and if you think you can follow those steps, try it.  Otherwise bring your bike to a bike shop and let them do it.


Whenever I get stuck wheelbuilding, I loosen every spoke one turn, walk away and come back in a few hours or the next day.

The worst thing you can do is keep doing something that is not providing the results you expect. It is completely possible to overtighten spokes enough that they stretch significantly under the tension. You can even break them with a bow and arrow like result that can be slightly terrifying. ( Fortunately the spoke was pointed at the ceiling and not me when that happened. )

Part of wheelbuilding is getting a feel for how much tension the spokes will support. There is a point at which tightening them further just does no good and actually makes the wheel worse, not better. In the past when rims where just boxes made as light as possible and spokes were more burly, you'd get wonky things happening to the true to let you know when you'd gone too far. Now most rims have enough structual shape that they won't deform that way and the spokes are much lighter.

In my experience out of round truing almost always requires adjusting all 4 quarters of the wheel. ( i.e. the trough as well as the bulge. ) You can't fix
it by just working on one section.

If tightening stops working, it's time to take some tension out of the entire build. Start by loosening the spokes you've been working on a half turn at least and then start loosening other spokes to achieve the affect you want. If that still doesn't work, loosen all the spokes and start over.


100kg is not super heavy and  well within the range of rider weights that bicycles and bike components are designed for. A decent quality seat and seat post should not break underneath you.

Some saddles probably do have a specified rider weight limit, in the same way the most bicycles do. I quickly looked for some information and found that Fi'zi:k actually explicitly states they have no rider weight limit on any of their products. I also looked at WTB but have found no information at this time.

Looking at the picture you supplied, and the description of what happened, I may be able to offer some insight. The seat in the picture is positioned very far back. If the seat that broke was positioned in the same way, your weight would have been acting behind the seatpost and trying to rotate it backwards rather than pushing straight down on the rails and post. You may have also over-tightened clamping bolt. These two factors would have over-stressed the bolt and caused it to snap.

I guess you fell off the back of the bike behind the seatpost, which would have been fortunate as you avoided being impaled on the post as well as breaking your leg.


Chain hops off cassette sprockets when I stand-pedal

You've got a 'stretched' chain that needs to be replaced.

If the chain has been in this condition for some time, and I suspect it has, I always recommend replacing the cassette at the same time. The reason being that a worn chain wears down the cassette and a new, unworn chain, will fit the old worn cassette poorly and the skipping will continue. I had to learn this the hard way, with multiple trips to the bike shop.

As usual, Sheldon has already laid the issue out in depth:
http://www.sheldonbrown.com/chains.html#wear


Puncture in SCHWALBE CITIZEN ACTIVE tire

A quick google shows https://www.schwalbe.com/en/tour-reader/citizen.html

Its a straightforward clincher tyre that may be used tubeless, but may be used with a tube.

Best thing to do is take the tyre off and see if there's a tube inside.

Do note that tubeless tyres can be run with tubes perfectly well.

From there, your question devolves to either :

how to fix a puncture in a tubeless tyre  or

to patch or replace a tube?  followed by either: how to fix a puncture in a tube tyre  or  how to replace a tube in a tyre


I'm starting to think I fooled myself somehow

And you are correct.

Smaller sprockets on the front or larger sprockets on the back give lower gear ratios (easier to pedal, but you go slower).


Effectiveness of disc brakes with brifters

As other have stated road discs are becoming more common. While hydraulic discs will give you the best performance, it comes at considerable cost. New shifters would be needed. Mechanical disc would reuse your shifters. I would put mechanical disc as a cost effective alternative. If this is an upgrade it is important to use road specific calipers. Mountain calipers and road calipers have a similar appearance but are not interchangeable.


Advantages / disadvantages of freecoaster and cassette hubs

My son wanted to change his freewheel/cassete hub to a freecoaster hub so I did some research about 6 months ago and found this great YouTube video from Odyssey and RideBMX magazine all about freecoaster hubs.

As you said, the cranks will not move when coasting backwards. For my son, this is the real advantage and why he wanted the hubs. Landing a 180 out of a half pipe, his freewheel hub did not allow great control of the bicycle requiring him to spin cranks as he rolled backward (just like that trick at 3:08 in your video).

In the end it came down to money and we (he 12 year old) did not want to spend the money to get a new wheel with a freecoaster hub, you cannot just swap the axle/mechanism/insides of your freewheel shell with a freecoaster mechanism, you need a shell/hub that supports the freecoaster axle/mechanism.


This is pretty simple. All things being equal, aerodynamic drag is a function of the relative wind velocity squared. Doubling the effective wind speed increases the drag force by a factor of four. Head winds could easily account for the loss in speed you are experiencing. Your body weight isn't a factor in dealing with head winds. Indeed if you are relative small, your drag will be lower than a larger rider. Weight is much more of a factor on hills, but in Florida that shouldn't be much of an issue.


What should I use to lubricate a freehub?

Freewheel (old technology) or freehub (current technology)?   People tend to use the terms interchangeably, but they are quite different.
A freewheel can be pretty effectively lubed with any medium-viscosity oil.  There's not much in there; a couple of ratcheting "pawls" and their pivots.

You don't want anything that will gum up and cause the pawls to stick.

On a freehub, the mechanism is pretty well-sealed and greased from the factory.  However, they are pretty easy to disassemble in most cases.
They do make a clever tool called the "Freehub Buddy" which lets you inject grease into the thing without disassembly.

However, at 40 bucks it's a bit steep for home use where you would only use it every couple of years or so.


The FC-2450 uses a Octalink bottom bracket. A newer 105 crankset would be a Hollowtech II, so at the minimum you'd need a new bottom bracket. You'll also need to make sure you can position the front derailleur for the change in teeth (probably can), and probably get a new chain to account for the extra teeth.

That being said, if you want a bit of change in gearing, changing the cassette rather than the crankset is probably easier and cheaper.


Slipping chain from lowest (largest diameter) cassette sprockets

This does not sound like a basic derailleur indexing issue, nor a bent derailleur hanger problem.

Possibilities that I can think of:

You have a broken or malfunctioning shifter. As you try to change to the larger sprocket the shifter is pulling the cable, the ratchet mechanism is not catching and is slipping back two places.
Your derailleur low limit is set too far in. As the shifter pulls cable it hits the limit, does not complete the shift and again slips back two places.
B-screw is badly adjusted to the top jockey wheel hits the 32 tooth cog and has the same effect as the low limit set to far in.
You are hitting the upshift lever while working the downshift lever somehow.
I suppose it might also possible that your indexing is off by one gear to the high side, so when you try to shift to the lowest ratio the shifter is already in it's lowest position, resulting in an upshift instead.

What I'd do to troubleshoot this is disconnect the cable from the derailleur, With the bike is a stand make sure the derailleur can shift onto all sprockets by pushing it inwards while manually pedaling (be real careful not to catch you fingers in the chain). Adjust limits or b-screw if you find and issue.

Grab the cable with some pliers, apply tension, work the shifter. Can you make the shifter slip on the last downshift position? If this is the case it's very likely the shifter is malfunctioning.

If you don't find a problem try reconnecting the cable and working through the Park Tool rear derailleur adjustment procedure to ensure correct limits and indexing.


There are several different sizes of chain based on the number of sprockets used in the rear cluster (e.g. 8-speed, 11-speed).  These are 3/32" nominal width.  Single sprockets for these chains are available, but can be hard to find and/or expensive.  In your application you may be able to get away with a slight mismatch, i.e. using a wider chain than your sprockets would suggest (an 8-speed chain on 10-speed sprockets, for example).  This wouldn't be a good idea on an actual bike, and it could get fiddly if you mix and match too much.  Here are the relevant spacings.

The alternative is singlespeed components - they use 1/8" chain and sprockets are always sold singly.

If you're going to pick up cheap used cassettes, I suggest you pick one type and stick to it.  All 8-speeds should work well together, or all 7-speeds, but less so for higher counts.  7- and 8-speed parts are cheap if you want to buy some new, while 5- and 6-speed can be hard to find and 10-speed or higher will get expensive.

As for the strength, consider the forces involved in hard pedalling - let's say a 100kg rider standing on a 175mm crank with the chain on a 22-tooth chainring.


What is causing the chain skip after chain replacement?

Yes, the stretched chain wears the chain ring and sprockets to match its pitch. It's recommended to use a chain gauge (such as this one by Park Tools) so you can replace your chain before it's stretched enough to do significant damage to the rest of the drive train. If you do let the chain stretch too far, you'll need to change the cassette/rear cog and/or chain ring(s).

The teeth of new chain rings have a mostly symmetrical profile; worn ones acquire a characteristic "shark fin" shape that's steeper on one side than the other and quite pointy at the top. On a one-by or single-speed bike, that's pretty easy to identify; on a bike with front derailleurs, be aware that the chain rings tend to have several teeth with funny profiles from new, to aid with shifting.


What is the drag / power lost to a safety flag?

If the pole is a flexible one, you can do the following:

Choose a windless day
Ride past a second person at a known speed
Let the second person take a picture while you pass
Repeat immediately in the opposite direction to capture the effect of the remaining wind.
With the bike still, pull the flag back, measuring the force somehow. You can use a spring scale, or just hang a bottle with different amounts of water on a string, connect that string to the pole, and run the string over pulley or a round, smooth piece of metal.
Take more pictures of how you are pulling the flag back.
Compare the pictures of the bend pole while riding with the pictures while pulling the flag back.

With this method, you get the force that the flag exerts on you while riding the given speed. Now simply multiply with your speed, and you get the power that's drained by the flag.

Note: Work with the correct units. 1kg weights 9.81N, and if you multiply the force in N with your speed in m/s, you get Nm/s = J/s = W. Just make sure that you convert the inputs to the multiplication correctly.


Replacing rear coaster brake wheel on 1959 Roadmaster

Because you're using a coaster brake, rim diameter is less critical an issue than in most cases. The size 24 x 2.125 is actually a tire size which corresponds to 54-507 in ISO measurements. That means that the bead seat diameter (diameter of the rim) is 507mm and the tire is 54mm wide. If the original wheel is ~24", it will correspond to BSD sizes between 520mm - 547mm (because there are lots of "24" size tires, read Sheldon Brown.) The new rim will be smaller...however... with a wider tire, it may make for a close fit. Match the old tire size with the link and you'll have a better idea of the original wheel-tire size as compared with your potential new size. Keep in mind that you can buy rather narrow tires to provide clearance for your fenders.

Another consideration is the Over Locknut Dimension (O.L.D. for short) which is how wide the hub is at the axle nuts (and correspondingly, how wide the frame is.) This is something that you'll need to break out a decent metric ruler to determine. You want to get that dimension close, but if it is off it isn't a big deal. +/- 5mm is an acceptable stretch. Anything more and you may want to consider either finding the correct width hub or swaging out the seat/chain stays to accept a wider or smaller hub (steel is a very forgiving frame metal.) Another option is to use a longer axle and spacers in a hub that is too narrow...something that you may want a shop to handle if you've never rebuilt a hub before, especially considering it will alter the chain-line.


Shimano RS785 hydraulic disc brake caliper will not reset

Thank for your detailed description and analysis of the problem.

I had similar symptoms with RS785 levers and RS805 callipers. I tried everything. Extreme force on syringe would only get a little oil into the shifter bleed funnel. Oil would not flow freely from the shifter funnel to the calliper with the bleed nipple open. Operating the lever would force oil down but not freely. Calliper pistons were slow to return, so the first pull on lever felt sort of OK, pulling immediately again and it felt hard.

I was not aware of the seal on the J-Kit (Easy Connect) system until I saw this photo which got me searching and I came across your post here.

You are correct. I disconnect the joint and a minute flap of white sealing material was causing the problem. I removed it using a needle and  re-bled the brake. Here is a picture of the removed flap with needle on a 5mm grid.

I did not have to replace the brake hose. The rear brake is working perfectly and feels the same as the front brake.

As to what caused it. I can only speculate. I wanted the brakes on my new bike swapped with Left = Front, Right = Rear (same as US, in NZ they are opposite). LBS swapped by changing over the Easy Connects. Assuming the brakes were operating correctly prior possibly this was partly to blame. In addition they introduced air and did not re-bleed the brakes so maybe that also aided the material flap in moving.

Another thought is that the seal was thicker due to manufacturing or material defect and did not burst but stayed intact.


It depends why the chain is tight.

If there's a chain tug then loosening that is the obvious way. Yes, it's slightly annoying to do that then tighten it up afterwards, but it's easier than the alternative. I use QR axles so for me popping the QR means I can slide the tug off without changing the adjustment and it's all easy from there. But even with a solid axle and nut you should be able to loosen or remove the nut and slide the tug off.

If not, just how tight is the chain? I've never been comfortable having the chain so tight that I can't just slip a tyre lever between the chain and chainring where a front derailleur would go and pedal the chain off that way. Often if the chain is too tight it's an attempt to compensate for bad chain line (ie, there's an offset between the cog and chainring) which is a problem in itself.

Edit: to fix this the only way is to add a link to the chain (so you have more slack), and that probably means using a chain tug to hold the wheel in place. You might not need the tug but unless the cost is critical I would add one. It's about $20 for a cheap one.


Styles of Shoe Covers for Colder Weather

I have 2 sets of shoe covers, and each has its advantages.
One are very much like the ones you show.  These are much warmer and easier to walk around in, but take a little more work to pull on (they are tight to the shoes) and while water repellent they are not waterproof.  They are perfect for riding in cold, dry conditions (down to, say -5C with good socks).  I've never had a problem with the zippers.
The other pair are waterproof cordura-type nylon.  They are mostly open on the bottom, except where they hook over the toe, velcro up the back instead of having a zipper, and have a velcro flap that passes under the arch of the shoe to hold them in place.  They are not nearly as warm and mostly good in heavy rain.  (Although even then water will come up through the screw holes in the bottom of your shoe.)  These are easy to carry (they fold up smaller), and faster to put on, at the expense of being mildly awkward to walk in.
Durability is an issue with both of them.  Pulling the neoprene ones on and off over the cleat has mostly torn the strap under the foot, and the toe part (mine comes partly down over the toe) is mostly abraded away from stepping down.  I have gaffer tape one one of them to keep the toe from popping up off my shoe.  The cordura ones the velcro is not holding well any longer, and I've occasionally had the strap under the foot come loose.  (Fortunately it hasn't gotten caught in anything yet.)


looking for Lightweight inexpensive children's bike (120cm) available in uk

Sadly the kids aren't the ones with the money, so some of the design of a bike is to appeal to the adult with the cash.  When I was a kid, single speed raleigh 20 was common, as were BMX.  You had to be pretty lucky to have a three speed, and only super rich people had ten speeds.   So the excess of gears is appealing mostly to adults.

If 120 cm is the height of your six year old, then that's about 10 cm above "average" so you're looking at a bike with 20" wheels.  Your son will be too small for a 26" wheel bike at this age, so expect this bike to be adequate till about the age of 10-11.  At that point he will be tall enough for a 26" wheel size but a smallish frame. Then somewhere between 15 and 17 he'll have stopped growing taller and that will be about the time to measure for a proper adult's size frame.

The point of all that?  Your purchase will have 5 years of use by your son at most.  So spending silly money on a specially lightweight kid's bike is a waste.  example: google for "carbon frame kids bike" and see how few there are.

Kids do tend to be a little rough on their toys as well - a lightweight frame will not endure being dumped, dropped, dubbed-on or used as a step ladder, as well as a "more robust solid bike"

There's no need to do this:

Because:


Cartridge bottom bracket with lockring on one side only

Your standard cartridge and "loose bearing" bottom brackets have two threaded "cups".

Usually the right (drive) side cup has a lip on it, so it will only screw so far into the bottom bracket housing.  There is no adjustment, and no need for one, since the distance that the shaft should project outward is determined by the design of the parts.  And if the bottom bracket is a cartridge one often the right side cup is permanently attached to the cartridge.

However, nothing is perfect.  If the cups do not tightly restrain a cartridge unit it will move about and make annoying clicks.  And if the cups are loose in a loose bearing style unit the axle will wobble around in the bearings.

So one side (at least) is made adjustable, without the lip on the cup, but instead with the threads extending a few mm outward beyond the expected distance it should be screwed into the BB shell.  This adjustable cup is then screwed in "tight enough" to achieve the desired pressure on the bearings.  But "tight enough" is not generally so tight as to cause the cup to "lock" in place like a regular bolt, so the lock ring is added to allow the cup position to be preserved, in spite of the various mechanical pressures that would attempt to turn it.

Note that this "adjustable cup" is generally on the left side, allowing the adjustment to be accessed without interference from the chainrings.

The vast majority of "3-piece" BB setups, at least on lower-end bikes, are of this variety, with one "fixed cup" and one "adjustable cup".  For the most part these units are interchangeable, so long as the style of the axle end matches (and there are 3.5 different styles).  There will be a modest variation in the length of the right-side shaft, between 2-ring and 3-ring fronts, but most 3-ring bearing assemblies will fit 2-ring bikes, and likely a fair number the other way.

A few bottom bracket bearing assemblies have adjustable cups on both sides.  This allows for various things, such as a BB shell that is wider or narrower than normal, or desire to adjust the "chainline", moving the sprockets closer to the frame or farther away.  It also allows a single BB bearing assembly to fit several (slightly) different setups.


Flat pedals are great for lots of reasons, but I won't get into the virtues or pitfalls of platforms versus toe clips versus clipless systems (though I am a big fan of plain old platform pedals.) I will try to give information pertaining to the different styles and a few examples rather than an exhaustive list of specific brands and prices. There are lots and lots of different models which are mostly variations on two themes: rat trap quill pedals and one-piece platform pedals. None are perfect, but many are cheaper and easier to use/maintain than clipless pedals.

Classic rat trap pedals have been around for a long time - one or two metal sides secured to a central body and quill (there were lots of poor quality pedals spec'd on bikes back in the day, but modern ones are generally of decent quality.) Variations use the same style of construction to much the same effect. Some people balk at using pedals without sealed bearings, but bearing maintenance on pedals is probably the easiest to tackle and shouldn't be an issue for most people. The VO Road pedals above use sealed bearings, while the MKS Sylvans use loose bearings. I would say they are both of reasonably high quality. They accept toe clips and reflectors and other forms of toe retention and are super easy to use (platforms on both sides so you can't miss.) A few brands make pedals that fold up so as to not catch on anything (MKS FD-7s...important if you have to carry your bike indoors frequently.)

Two drawbacks: these pedals are generally not as grippy as some others, noticeably in the rain/snow. Second is that the construction can be felt through thin shoes. In Chuck Taylors with thin socks I found the dip in the MKS Sylvans to be a bit uncomfortable. Generally folks don't mind it, though.

Track pedals are narrower and only have a platform on one side as they're intended to be used solely with toe clips and straps. These are great if you love toe clips, but there is no back side to the pedal so they're somewhat limited in flexibility. On the plus side, they're lightweight and narrow so that you can clear obstacles (cars, curbs, doorways, people's ankles...)

There are also many machined and forged one-piece pedals based on the above designs (plastic versions I've seen are not worth consideration.) Velo Orange Touring pedals are surprisingly light weight and use sealed bearings (their narrower Urban pedal would be comparable in width to a track pedal but still has two useable sides.)

BMX style platform pedals are super popular and work for lots of people. The cheaper ones are probably the most affordable/functional pedals out there. These pedals range from fat and chunky plastic to graceful CNC aluminum (and there are lots of garish colors out there for those into color-coordination.) Some of these pedals have provisions for reflectors and most allow for strap-type foot retention (but not toe clips.) The more expensive pedals will have sealed bearings, but you generally get what you pay for. The big benefit of this style of pedal is that they have a nice flat platform with lots of grip. Metal platforms frequently have pins set into the tops to add grip which, if you've ever ridden these pedals in shorts, leads to frequent bloody shins (so avoid expensive pants or delicate leg skin.)

Cruisers and utility bikes will sometimes have plastic or composite pedals with rubberized tops that don't tear your shins into ribbons. I have a set of VP 001 Thin Gripsters and they're great for commuting and hauling around town. They do have sharp little nubbins, but I can deal with it as they're really shine in the rain and snow. They're noticeably thinner than other platforms (hence the name) but they're wide and long so I never misstep.

The big drawback to these pedals is that they're heavy and wide (plus the bloody shins, but I covered that.) The weight is a compromise in any case, but the width can sometimes be a real problem i.e. a low bottom bracket with long cranks will dig your pedal into the pavement while cornering. Similarly, riding a bike with lots of toe overlap on the front wheel will lead to endless suffering in tight places. These can be avoided with careful maneuvering but will surprise the unawares.


Information regarding UN300 and UN100 (new Shimano Bottom Brackets)

On the german Shimano site the UN300 is a bottom bracket designed for (e-)MTB. It is advertised as available in 3 versions: standard, E-type and closed gearbox (I think it is the spindle&co. without the housing). Different lenghts are offered.
It is advertised as part of the "Shimano Acera" family of products.

The UN100 is advertised as part of the "Shimano Altus" and "Shimano Tourney" family of products. It explicitly mentions being compliant with two specifications only (D-NL and LL123)


Can I swap the lock out on one suspension fork for the remote lock out on another?

Yes, assuming they are both remote capable. Rockshox uses the same lockout on all the models I have seen. Should be no issue and will only take a small allen wrench. You will likely need to remove the grips, brake lever and shifter from your left handlebar.

IF the new fork is not capable you may need a remote lockout top cap, which is a bigger question.


If your goal is to convert your 3 gears in the front and 7 gears in the back to a 3 in the front and 9 in the rear this will be quite expensive. A new rear wheel will be required Your current rear wheel uses a screw on freewheel to mount the rear gearset. Nine speed rear wheels use a freehub mounting system with a cassette. You will need a 9 speed rear shifter and derailleur of the same brand, Shimano shifter with a Shimano derailleur or Sram derailleur with Sram shifter. You may need a new front derailleur, some 7 speed front derailleurs can be adjusted to work with narrower 9speed chains but it is trial and error and shifting may not be optimal. If you front shifter is a non indexed type this may actually improve shifting in this mismatch scenario. You will need a 9 speed chain. If you are doing these improvements yourself you will need to add the cost of a chain-tool, freewheel removal tool, cassette install/remove tool and a chaiin whip.


Handlebar positioning and posture on Giant bikes

The Cypress is a comfort oriented bike that has a deliberate high handlebar position and upright riding posture. Almost all other bicycle types will have a much lower handlebar position.

If you look at the Cypress on the Giant website, you can see the bars are above the level of the seat. On the Roam and Cross City they are about level. General handlebar height is built into the geometry of the frame, but the angle and length of the handlebar stem also affects it. Notice that the Cypress has a stem that raises the bar height considerably.

Handlebar height can be adjusted on most bikes, but only by a a few centimeters. It is possible to raise the bars more by swapping the stem for a 'riser' stem as seen on the Cypress.

The best approach is to visit local bike shops, test ride some bikes and find one that you are happy with. It's always best to buy the bike you actually want in the first place rather than trying to modify one after buying it.

A good bike shop will help you find the bike you want, and would probably be willing to swap the stem on a bike for a riser (if they have one in stock) for a test ride.


Replacing needle bearing threaded headset with an ordinary one

In replacing a threaded headset on an older bike, there are two other considerations we need to make beyond selecting between ball bearings or needle bearings (though, IMO needle bearings are ideal for a number of reasons that I won't get into.)

First, you need to measure the stack height. Stack height is the amount of space the headset takes up, not including the parts that fit inside of the head tube. If you measure the entire length of the steerer tube and subtract the height of the head tube you wind up with a difference that is taken up by headset cups, bearings, the keyed washer, and the lock nut. You can add or subtract spacers to make fine adjustments.

To measure the stack height, simply measure:

You'll wind up with a measurement in millimeters. Try to find a new headset with a stack height equal to or less than what you have. If there are spacers installed (smooth or knurled rings between the top lock nut and the upper race) ignore them, but be sure to include the height of the lock nut and keyed washer (just under the lock nut.) If you wind up with a new headset that is just slightly too tall, you can omit the keyed washer if you use some thread locking compound on the lock nut, but it would be better to just get the right dimension in the first place.

The second thing you need to do (and this will be more difficult) is to verify that you have an ISO headset (as opposed to a JIS headset... more extensive information about different headset measurements and how to adjust them Sheldon Brown and Headsets here.) ISO is the standard size, but JIS headsets were used on lots of Japanese and Taiwanese bikes from the 70s until the early 90s. There are many other sizes, but for most 90s bikes this will suffice.

To finally get to your question...no not all bicycle headset frame cups are identical. Another measurement, the diameter of the fork crown seat, also varies between standards. Two common threaded headsets you'll run into are 1" ISO and 1" JIS and they are ever so slightly different. If you have access to a lock nut wrench and metric calipers discerning between the two will be pretty straightforward.

Remove or loosen the fork in the frame enough to see the fork crown race when you push the fork down and lift up the bearings and retainers. You need to measure the inner diameter of that fork crown race.

The fork crown race in the photo is bronze colored, while the seat at the bottom of the steerer is silvery. The seat is slightly larger than the steering tube, so measure right where the seat and the race meet. In an ISO headset that measurement will be 26.4 mm. In a JIS headset that measurement will be 27.0 mm. I will tell you from my own experience that the two are not interchangeable. Additionally, the frame cups for an ISO headset are 30.2 mm in diameter while JIS cups are 30.0 mm. It is much easier to fudge installing 30.2 mm cups in a frame designed for 30.0 mm cups, but have a shop do it (and only in a steel frame.) Finding cheap JIS headsets is easy enough and, like I said, ISO is pretty standard.

One final note: replacing a headset is actually pretty doable for most people so long as they're careful and reasonably clever. If you're unsure about any of the steps you should take it to a shop. It is a quick installation and relatively inexpensive. They have all of the right tools which will make the process far easier than using homemade tools.


Can anyone identify this Tandem bike I restored from a junk yard?

I had a very similar frame on a tandem from Craigslist several years ago. That was a Schwinn.
The frame is terribly flexible, you can't put an adult on the rear seat.


With friction shifters this is usually caused by one of two problems:

Loose Shifter Screw: Friction shift levers usually have a wing-nut-screew used to adjust the tension and friction of the lever against the mounting housing.  Tighten this screw, but not too tight or else you can't move the shift lever.  You can also take the shifter apart (noting carefully the order of the parts) and clean everything with degreaser.  DO NOT LUBE - you are trying to regain friction, not remove it.

  Edit re. ʍǝɥʇɐɯ  - After you adjust everything you may find that the shifter screw continues to come loose almost immediately - in that case you may want to use a little 'adjustable/removable' Loctite on the screw, assemble, and let it sit for a while before using.  That should help hold everything together.

Cable Friction: Often there will be one or more points of friction on the cable route.  This could be in the housing, or in the routing channels under the bottom bracket.  As you apply pressure to the pedals the frame flexes, pulling the cable one way, but then the friction stops it from sliding back.  Check and clean your housings and routing points, especially at the bottom bracket.


Chain getting in between sprocket and rear dropout

Yes, you need to adjust the limit screws of the derailleur so it can't pull the chain farther over than the last cog.  There are various videos on YouTube, such as GCN's:


Replace SPD pedals for road pedals... which system to choose?

I've ridden commuter and road racing bikes both for decades and can validate your decision to go specific in regards to your shoe/pedal setup.  Start with the shoes - try a bunch on and find a pair that really fit well and seem to work for you.  Most modern shoe/pedal systems use the three bolt pattern common to Shimano and Look systems so there's not a lot of compatibility issues anymore.

Speedplay is the outlier for sure here - I wouldn't worry so much about single sided vs double sided.  Getting in and out is a bit trickier for road systems but you'll figure it out quickly regardless.  What you want to concentrate on is float and release pressure.  Since you're used to clipless on your commuter, it will be fairly straightforward to try systems out.  Work with a retailer who will let you try different systems while using a trainer, that way you can get a feeling for how they work.  If you don't have a retailer close by who will let you do this, look for a fitter and ask them to fit you.  It costs about $100-$150 to get fitted properly with new shoes and pedals on your bike but it's well worth it in the long run.


Are road caliper brakes usually compatible with any model of lever/STI shifter?

Pretty much right -- you just have to make sure that the calipers have enough reach to brake (on an Allez, pretty much anything but a long reach caliper will work). There are some threads like this with some new Shimano stuff (new Super SLR) which is technically a ymmv/you're on your own, but it should work.

Another thing you should check when replacing the brake is that the cabling was done properly -- bad brake cable routing, for example, can make your brakes not feel good.


How to install rear rack & fenders on a vintage road bike

Does this frame have mounting points down on the rear dropouts?  The sort  sometimes used for mudguards/fenders, which can be repurposed for the downshafts of a rack.  Since they hold most of the weight, a front mount is relatively lightly loaded.

I made a couple of clamps out of thin sheet metal for my rack, which wrap around the seat stays and bolt through the rack.

View from above

Looking backwards

Each bracket is a short strip of aluminium which is wrapped around the seat stay and then back on itself.  The bolt is a stainless steel one, and is (edit: should be!) double-nutted for vibration resistance.

Remember at least 2/3 of the weight is taken by the rear struts.  I've had a good 12-15 kilograms on this rack.   The black plastic is a substitute for a mudguard/fender, which does fine protecting my backside and bag, but does little to keep the bike and chain clean.


Bunny Hop, Stoppie or Wheelie? Which one to attempt first on MTB?

Overweight is relation to height rather than age, but that really isn't an issue at all with performing "stunts". I am 175 and was in the x-games performing "stunts". The most useful "stunt" in the sport (that I can think of ATM) is the bunnyhop! This basic maneuver is the one that will get you further in this sport than almost anything else. You can get over curbs, rocks, rivers, cracks, etc. Wheelies are cool and help in skatepark contests, and for a short distance might help with getting up on things, but it is really just the first step in a bunnyhop. Wheelies are the only trick where weight can be a factor since you will be torquing your chain, but that shouldn't matter in your decision (going up hills does the same thing). Endos (stoppies) are not practical for anything I can think of except to practice front end balance. Bottom line: LEARN BUNNYHOPS FIRST!!


Trek 3700 XC Hardtail - looking to convert to temp road bike

If you want to use a mountain bike on the road, you put on slick tires (this is all I'd recommend doing for bang for your buck).

I wouldn't recommend changing out the wheel sets, since this is pricey and doesn't give you a ton of gains unless you're really at the top.

A rigid fork would be a bit lighter, but you do need to match it to the type of fork you have there (this would be a good thing to consult with your LBS on, given that you need to get the fork cut and what not). I don't think this is strictly necessary (weight isn't that much of a killer, and this is a bit pricey for a bike that the kid is going to outgrow in a few months) - just lock out the fork (if you can) and move on with your life. It isn't ideal, but it wont make or break you.

Most importantly is to probably fit the kid as best as possible to the bike you have.

Also, 31 inch inseam seems high for a 5'2" kid.


It seems that the problem is that the cable is not beign pulled through the hose. this can be caused by various things:

Get your chain on the bigger chainring and shift down, since the derailleur does not shift properly, try to move it by hand. if you feel just a little resistance you should check your routing and/or change hoses and cables. if the resistens is strong, do not apply to much force. In this case check if the limit adjuster screw is preventing the chain from moving onto the smaller chainring. you should find two screws on the derailleur which are responsible for setting the upper and lower bound, e.g. prevent your derailleur from moving the chain to far.

hope that helps!

PS.: make shure that the cable is routed the right way, it looks kind of wrong in the posted picture (near the point where the cable is clamped).


Sheldon Brown to the rescue: "Shimano uses the trademark "Hyperglide-C" to designate a system with an 11 tooth sprocket. The "C" stands for "compact". These systems are used with smaller-than-usual chainwheel sizes, or on bicycles that have a small drive wheel, or to achieve higher gears.

Due to clearance problems, the cutaway between the splines on 11-tooth sprockets only goes halfway through the sprocket. The matching splines on Hyperglide-C bodies don't go all the way to the outer end of the body."

To summarize: Hyperglide-C cassette on non-hyperglide C body gives wobbles (which you can correct with a 1 mm spacer).

In the reverse case, you can remove some spacers from your cassette (if you have them) to get it to fit (though I'm not really sure when this case would practically occur).


Direct Pull (V-Brake) vs. Center Pull Cantilevers (pros and cons)

The main reason that the direct pull (V brake) was invented is that it approximates a center-pull cantilever in terms of balanced force and leverage, while not requiring that the cable be anchored at some point above the wheel.  This is important for front wheels on suspension forks, but not significant for most other uses.

Another slight advantage of the V brake is that it doesn't generally protrude out of the profile of the bike quite as much and is thus somewhat less likely to be damaged in off-road use.

Neither advantage is of any importance for a road bike without a suspension fork.  However, there is the problem that the two require different levers (because the cable travel length is different) and the old cantilevered levers are getting hard to find, should you break one.


In many cities, doing a 35 km (22 mi) commute will take you through parts of the city with different socioeconomic levels and different driver behaviors.

Cyclist behavior that works well in one part of the city can lead to road rage in another place. It's valuable to recognize this and adapt your approach at different parts of your commute.

Some years ago, my commute took me through some quiet streets of a well-to-do suburb of mostly older residents. It took a few interactions, where a driver would look right at me and then apparently try to run me down, for me to realize that they simply didn't see me. They were looking for cars. It's like These are not the 'Droids you're looking for. They are looking for cars, not bikes.

Knowing the area you're riding from, I would describe it (for other readers) as rural / urban interface. There are new developments, and little infrastructure. Roads become congested early, and stay congested late. It's also Winter here now, so it's often only half-light or dark when commuting. Because of the ongoing development there is a higher than usual number of tradesmen (tradies) driving utes (pickups for US readers) and commercial vehicles. Their focus is on getting to their current job. It's not an area where I would choose to ride.

So, either recognize the local conditions and adapt to them in a safe way, or find another route. Another route may not seem practical, but on a 35km commute, a safer route that involves a 3km detour will not be much slower (it may even be quicker), and could save you hospital time in the future. You could maybe drive a short distance to the start of your safer route.

Another change you could make is to use a helmet-mounted light. They shine where you look. So when you look, the drivers are more likely to notice you. Be careful not to get one that's too bright though. If you dazzle the driver then they actually can't see you.


135mm quick release hubs are still common. 26” 135mm 10 speed cassette compatible wheels should be easy to obtain.

Make sure to get a Hollowtech BB that is specific to MTBs. These fit 73mm shells and 68mm shells with included spacers, and are compatible with MTB cranks. Road Hollowtech BBs only fit 68mm shells.

For the rear derailleur, "23-28t Close ratio" and "32-36t Wide ratio” refers to the size of the largest cassette sprocket supported. If you want low gears you want the wide ratio option and a 11-32, 11-34 or 11-36 cassette. Do some research or gear ratios to decide what range you need.


Need help with picking right shoes for riding my new bike

You may look at changing your pedals, instead of your shoes.  Many companies make flat pedals with pins to keep your foot/shoe on the pedal.

Keep in mind there are trade offs.  Your current pedals may have no grip, but you can probably ride them barefoot, in flip flops, etc.  More agressive pedals will most certainly keep your feet from sliding off, but are also famous for causing shin and leg injuries when they catch you unawares.

You may also look at cages which will hold your feet in place as well, but are a bit harder to get out of (meaning you may get your foot stuck and fall).

Either of these styles of pedals should be purchasable for about the same, or less than a new pair of shoes, and should likely last longer than any cycling specific shoe.


Welcome to Stack Exchange.
You are dealing with a one piece crankset.  This Park Tool video shows the viewer how to get this done. More common tools to assist in this job is an adjustable wrench ("crescent wrench" is a specific brand and type of adjustable wrench but that phrase has morphed into a synonym for adjustable wrench).  A flat bladed screw driver.  A hammer. Needle nose pliers.  In the video, the gentleman uses a special bicycle wrench to remove that ring (it's a threaded cone nut). In your pic, you've got the hex lock nut loose.  The keyed washer remains in place and partially covers this cone nut. Note the slots in this piece.  You'll have to figure out a way to engage these slots so you can torque this piece loose and unthread it completely. You can use the screwdriver as a punch by positioning the blade in one of the slots and tangent to the ring.  Use the hammer to tap on the screw driver's handle so that you can "break loose" the cone nut's threads.  Once it breaks loose and starts to turn (to the RIGHT---see next sentence), you can come in with your needle nose pliers, engage both slots and continue to loosen until you can use your fingers to complete the removal.  Try engaging the slots with the pliers and attempt removal first.  These cone nuts aren't installed with a great amount of torquue, but time and corrosion may have frozen it in place and it may require a little "persuasion" to get moving. Make sure the keyed washer is off before all this. PLEASE NOTE: on this left side of the bike the pedal, locknut and and cone nut are LEFT HAND threads so to remove, one turns them CLOCKWISE.

In your question, your description of the pedal is a bit confusing.  Typically the pedal will thread into a hole at the end of the crank arm.  Often its a 1/2 inch spindle on these types of cranks but could be 9/16". (Metric equivalents are 13 and 15mm respectively).  There are wrench flats on the end of the pedal spindle where it joins the crank.  Sometimes the pedal is threaded and torqued tight by the use of a hex key placed in the hole found a the end of the pedal.  If you dont see any wrench flats on the outside, look to the inside--the end of the pedal spindle where it comes thru the crank arm for this hex-key slot.  Your pic just cuts off a view of this on your right pedal.


Get your sit bones measured.

Bikes are made in different sizes, handlebars in different widths, cranks and stems in different lengths, seat tubes are adjustable.  Why all this variation?  Because people are built differently.  So why just choose a saddle that "should be good" and go?  Get your sit bones measured, then buy a saddle from a company that makes different width saddles to accommodate different riders anatomy accordingly.


Returning to bicycling after a long hiatus

Age is a big factor - if you are 20, you probably can get away with going straight into it, if your over 50 (like me), the body is less willing than the mind, much better to take it easy. Some people bounce back fast, others take a bit longer, so there is no way to say what you should do.
Main risk is going too hard, too soon and suffering an injury. Start with short and slow rides, listen to your body, and build up to your 20 miles. Over doing it and injuring yourself means you time to get back to normal capability is significantly increased and inconvenient.
Keeping in mind the age thing, what I would do is something like 5 miles slow, adding 10%-20 per week until your up to 20miles. Mix it up with some short faster rides, increasing speed by 10%-20% effort (not actual speed) per week.
You get do not get fit exercising, you get fit recovering from exercise.


The derailleur in the first photo doesn't appear to be mounted correctly. See how there's a big gap between the axle and dropout slot? I think you should just go with a regular, bolt-on derailleur. Non-replaceable hangers are usually found on steel frames (check yours with a magnet) and are perfectly fine to use. With steel, you can just bend it back into shape if broken, or even cut it off and weld on a new one if i remember correctly. Any 7 speed (it might even be 6/7/8 compatible) derailleur should be the right one.
The chain skipping could be caused by worn out drivetrain components like you mentioned, or it could be due to the wonky derailleur setup. I would wait until the correct parts are installed and it shifts fine before sorting that problem out.


Does my rear tubular tire need to be replaced?

Yes. It needs to be replaced.
When the rubber tread is worn so far down the carcass is showing the tire is dangerous. The fabric carcass cannot provide grip like the rubber can so you risk losing grip in a corner and wiping out.


Unable to shift to lower gears; Shimano 6 speed SIS rear deraillers

There are several things that could have gone wrong, some listed in previous answers. But one question to start with: What sort of shifter do you have? Shimano SIS is normally a thumbshifter but your description sounds as though it might be a twist grip or push-button shifter. The problems for each can be slightly different.

All of the following will be easier if you can lift the rear wheel off the ground so that you can spin the pedals and change gear while you experiment. Flipping the bike upside down so it's resting on the saddle and handlebars is sometimes the only way to do this.

Since you have more than one gear working, the cable moves in the housing and is probably still intact. It may have frayed at a bend and be jammed up, with just enough movement to let you use two gears.

If your bike has suffered an impact there may be obvious damage - a bent derailleur or broken shifter. This should be obvious.
if there is exposed shifter cable along the frame tubes, try pulling on that while gently spinning the pedals. Be careful because if the derailleur is bent this may cause it to move into the rear wheel, potentially damaging the wheel or derailleur. The gears should change. Work out which cable changes the rear derailleur and see if that gives you the full range of gears.

If so, it's probably the shifter,
If not it's probably the derailleur.
If the cable pulls right out of the bike, the cable is broken.

Next, shift to the lowest gear you can, stop the rear wheel, and pull quite hard on the cable. With thumbshifters and twist grips, pull hard enough so that the gear lever moves to the highest gear. With rapidfire this won't happen so just pull as firmly as you think is reasonable. This does two things: if the cable is frayed, it will hopefully snap; if there's a sticky point somewhere in the system, it will probably give way.

If the problem is just the cable sticking in the housing and you don't want (or can't afford) to replace it, lubricating the cable will often solve the problem for a while at least. Most solvent-based chain lubes will do this just fine. Thereś a video at http://bicycletutor.com/lube-brake-shift-cables/ showing exactly how to do this.

A bent derailleur can often be straightened, and with a 6 speed, if it looks straight it usually is. If you break it off while bending it back you haven't lost much, since the alternative is buying a new one. If it does bend back you win.

If the derailleur just won't shift far enough any more, you'll need to check for more subtle problems. I'm not sure I can talk you though those.

If the thumbshifter is broken, you need to replace it.

If it's a broken cable, the Park site @Jay Bazuzi linked to will show you how to fix it.

The easy option is, of course, to take it to your LBS. It should take the mechanic about 30 seconds to work out where the problem is, and they will either bend the derailleur back or replace the broken part. Unfortunately old, cheap gear systems are usually not repairable or worth repairing. The good news is that replacements are cheap. The bad news is that if you bought the bike second hand, new replacement parts will probably cost as much as the bike.


How do I make my pannier bag less smelly?

I know it sounds too simple, but these bags are made to be cleaned (assuming yours is unlined. If it's lined, you'll never get it out).

First, try dish soap and water. Citrus scents seem to cut the smell best, but that may be a personal preference.

If that is not enough, then the next best option is to use a diluted solution of something like Pine Sol or other bath, kitchen and tile cleaner.

I've used Pine Sol in a 1:4 ratio with water, and it did the job that dish soap wouldn't.

Another thing to consider:

Seal the products you are carrying better.

Don't take fish just wrapped in newspaper like the fish market gives them to you. Ask for, and insist on if necessary, a ziplock or similar plastic bag or wrap to keep the fish oil off of your bag.

For Gym clothes, pack them in vacuum storage bags like you get for packing luggage tightly. Push the air out of the bag, and it will keep the nasty sealed in well enough to keep your bag form smelling.

They come large enough to put most anything that will fit in your panniers or messenger bag, (even newspaper wrapped fish), and they don't take up much room when empty.


Most likely you need:
3/8" diameter
26 tpi (thread per inch)

On the website below there is a list off all Shimano gear hubs which use this size nut:
https://www.sjscycles.co.uk/hub-spares/shimano-nexus-brim40-cap-nut-38-inch/

Please check if your hub is listed to ensure compatibility.

Source: https://forum.cyclinguk.org/viewtopic.php?t=98948


Since it's a new-to-you secondhand bike, for safety's sake as well as to deal with the sluggishness I recommend you take it to a bike shop for a complete overhaul. I'll bet you'll be astounded at the difference when they're done.


Which bolt to use when aligning disc brakes?

Should one adjust the caliper on top of the bracket? Or should one adjust the bracket on the fork?

For Magura parts, you'll adjust the caliper. It's impossible to predict what would be the case for every brake assembly that will ever be manufactured, so your question about the future cannot be answered with certainty. But if you ever see an intermediate bracket like that, engineering concerns dictate a very high probability that you'll always want to adjust the caliper itself, rather than the mounting of the bracket it's secured to.
The part secured by the blue screws is the QM26 adapter used to allow the caliper to work with a 203 mm rotor:

The red screws then secure the caliper to the adapter. It is those screws that you need to loosen before aligning the caliper:

The diagrams above are from the owner's manual. The instructions that go with the second picture read in part:

Installing brake calliper

…
Screw in retaining screws top (M6x35)(11) and bottom (M6x33)(12).
The brake calliper can still be moved slightly but only wobbles slightly
Pull and release the brake lever several times
Pressure point is clearly noticeable and does not change.
Pull and hold brake lever.
Tighten retaining screws alternately and in stages to a tightening torque of max. 6 N-m (53 lbf-in). [A7][A2]

Note particularly the last two points. Disc brakes in general are finicky to get adjusted right (well, even many rim brake designs are too), but it's important to make sure you are holding tension on the brake lever to secure the caliper in line with the rotor, and tightening the screws carefully so as to not disturb this alignment.
Assuming you've already done all these things, then you may have things aligned as best as you're going to. The brake pads ride very close to the rotor, and minute vibrations resonate well through the brake parts and bike frame, so the tiniest irregularities produce noticeable noise. Often once the pads have been worn a bit, things get evened out and the noise abates or disappears completely.


Is there a "conventional" configuration for mounted accessories?

For commuting with panniers and/or a toddler seat, I've settled on the front fork for the D-lock, mainly because little else fits there and I'm restricted by cables and tube diameters elsewhere. Having that 1.5kg forwards also helps the handling with a heavy back load. Don't forget that a heavy lock is only around 2% of a rider's weight - it has to be a long way from the centre of mass to be noticeable for handling.

A cable lock will often fit in a spare bottle holder. I actually use the down tube holder for this, and the seat tube  one for my bottle. But I'm usually in stop-start conditions (for longer rides I use both bottle holders for bottles).

My pump actually fits under the down tube with around 10mm clearance to the mudguard.

My puncture kit (including for humans) and other tools go in a small triangular bag in the front of the frame. A saddle bag doesn't fit with the toddler seat. I'm lucky in that I normally lock up somewhere I'm happy to leave tools and lights on the bike.

As for convention, if there is one I ignore it. Personal preference combined with quirks of bike design are much more important.


To go from a 1x8 to 2x10 drive train you will need:

Replacement shifters for 2x10 drive trains
Front derailleur for double 10 speed crankset
Double 10 speed crankset
10 speed chain
10 speed cassette
10 speed rear derailleur
Cable outers for front derailleur


Option #4 won't work - the spacing between the cogs is different for 7,8,9 speed (4.34 mm for a Shimano compatible cassette for 9 speed, 5 mm for 7 speed Shimano). An index shifter is designed to move the chain over by a certain amount based on this spacing, which is why you have to typically match the number of speeds on the shifter with the cassette. Note that a 7 speed, 8 speed, 9 speed chain can usually be used on any of the 7/8/9 speed setups though (not necessarily optimally, but it usually works out with a bit of adjustment).

The cheapest solution is to just buy a 7 speed cassette and put it on, and is likely the best (#2). 7 speeds chosen appropriately is more than enough for almost everyone.

Disassembling a cassette is a hassle and its likely you won't get the spacing correct anyway, so #3 is out.

Option #1 is a decent option given 9 speed alivio or whatever shifters are not too expensive now, and you get a fresh set of cables if you buy a set of Alivio shifters. But, if you have brake-shift combined units, you may also have to buy new brake levers. Its also more work, but if your shifters aren't working too well, this is a good choice - there isn't much on the market for good quality 7 speed shifters anymore, so if you're going to be using the bike a lot, this may be a good choice (I just upgraded my 7 speed commuter to 8 speed because the shifters went).

To conclude, option 2 (installing a 7 speed cassette) or option 1 (installing 9 speed shifters) are the only ones which would work. Option 2 is cheaper (and I'd likely go for this if the shifters are in good working condition), but option 1 is a decently reasonable one as well (and is recommended if it looks like the 7 speed shifters will go).


It's hard to tell exactly what was done and why – it would help to know the original and new tire sizes. But what it looks like is that the shop added inline barrel adjusters to your brake cables. That's consistent with your description as well. They probably added them because the release levers on the brakes didn't give enough clearance to remove/install the wheels with the new tires without having to undo the cable clamp bolts. This is to make it easy for you to repair flats and the like.

I would have expected the shop to contact you and tell you that the new tires were too wide to work with your current brakes and offer you options for the solution. One solution would have been to use a narrower tire, another is adding the barrel adjusters.


Partial answer - you are looking at a frame design known as "crank forward" or "semi-recumbent"

The backreset is an integral part of the "seat" because the rider pushes against the backrest to power the pedal, and cannot raise themselves off the saddle and onto their pedals.  The rear suspension makes it a bit more comfortable given you can't unweight for bumps.

I'm going to hazard a guess that its an asian-source bike, and probably aimed at the elderly.


If you have flat bar shifters, most bullhorns have a different diameter than flat bar shifters use. But you can find bullhorns which have the same grip diameter as flat bars and clamp the shifters on (though these are comparatively rare). Then you have to make sure the ergonomics work for you.

My suggestion if you want a few more hand positions is to buy some bar ends. Ergon makes some fantastic ones, albeit a bit pricey.

Edit: I saw STI shifters, which normally is just used for the drop bar brifters, so the remainder of the answer may be useful for that.

The bullhorn diameter has to match (and most bullhorn bars satisfy this, though you can also get bullhorns for mountain diameter). Worst case, you can always cut a drop bar to get a bullhorn.

The bigger problem though is that you have to shift -- the STI shift motion is pretty hard to pull off on anything other than a standard drop bar. The cable routing is a bit weird, and its not necessarily the case that you'll be able to fully use the brake lever when using STI shifters depending on how its installed (actually thats probably the biggest problem -- you don't need shifting but you do need good braking). Also, the ergonomics of a STI hood were designed for a drop bar

People have done this though and some people like it. Bar ends and aero brake levers are neater to route and likely easier to shift/brake with though.


How do I select a rear deraileur for my mountain bike?

A derailleur for your mountain bike should match the specifications on the original derailleur. That is, while it doesn't need to be the same model of derailleur, it does need to be the same brand, in almost every case.

It also needs to match the number of gears, or have more intended. Meaning a 7 speed will fit for 5 and 6 speed bikes. An 8 speed will work for 7 and 8 speed. A 9 speed will work for 8 and 9 speed, and sometimes 7 speed (but no promises.) A 10 speed mountain derailleur has more limitations. It may work with 8 or 9 speed, or it may not, depending on model and brand, and other variations. It is the newest, and least tested, with non 10 speed systems.

In addition, the cage length, either short, medium, or long, should be the same as the original. If you don't know what yours is, then long is the safest bet, but you may also need to change the length of your chain. The difference between long and short cages is the amount of chain the derailleur is able to absorb, which in turn determines the size of the gears you can run, particularly as relates to the front chainrings.

The large plastic pulley derailleurs you have seen are called Mega Range derailleurs. They are generally used for department store quality bikes, or hybrids, and are definitely not intended for a mountain bike. They give a very easy climbing gear, but are low quality, and often shift very poorly.

I hope that helps. If you need more info, feel free to ask.


Assuming this is the bike you are talking about

Zycom My 1st ZBike
According to the assembly video on their website (I couldn't find a manual)
The fork and handlebars are held together with a clamp

And the seat post is held into the frame with a clamp

The two clamps look similar but might be slightly different sizes. Swap them back and forth to make sure you have the right one in the right place. If one clamp is a little larger than the other the larger one could be for the fork/handlebars leaving the smaller one for the seat post clamp.


LBS said creaking under torque is normal?

First, to respond to the issue of your LBS -- you shouldn't be made to feel foolish or to feel obligated to purchase expensive replacement parts. The lack of attention and reassurance you're getting suggests that maybe you need to take your business elsewhere (which can be difficult if there are few local options).

Second, your creak/tick is not normal (and, as many have rightly pointed out, could come from many components which carry your pedaling force). While there are a number of components which have a tendency to creak or tick while remaining safe and functional (your BB for example), what your LBS should have checked for is any integrity issues with your frame (though, they may have done so and not mentioned it. Who knows?)

Bicycle frames (Al, CroMo, Ti, Carbon Fiber...) can develop cracks in a number of places which, when stressed by pedaling aggressively, can generate creaks or ticks in time with pedaling forces. Some bike frames will live decades with cracks while others can--and do--fail catastrophically (i.e. your head tube tearing off...though, thankfully, this is infrequent).

I recommend that you take your bike to a different bike shop and ask them to investigate this potential problem (more info on frame inspections here). If they're good, they'll give you sound advice about repairs or replacement (avoid trashing your other shop, though. It's bad etiquette.)

If the noise is a component, a good shop will solve the problem; a mediocre shop will replace every component one-by-one until the issue is solved (and a terrible shop will try to sell you a new bike!) Understand, however, that nuisance squeaks and creaks can be quite common--even for experienced cyclists.


What's a good, reliable mountain bike drivetrain (1x10?)

I won't suggest any brands but here are some ingredients that will allow you to go cheap and reliable:

go 1x9. 2x is more expensive, more noisy, heavier and generally problematic if you can get away with 1x. Just make sure you calculate some possible ring and cassete options so you know that you'll be able to tackle all ascents and descends you need to. A spreadsheet works great for that. Divide ring teeth to cassette teeth to find the ratios that you need. Ride friends' bikes on ascends and descends for find your numbers.
bashguard: Do you really need it? Please check on your existing one whether you see impacts. Have you used it so far? If not, you don't need one. Especially now that you'll go to a single and smaller ring, chances that you really need one are very slim.
chainring: Go with a "narrow-wide" one. There are at least 5 companies making such rings now. The narrow wide pattern of the teeth allows for maximum chain retention eliminating the need for a chain guide.
rear derraileur: Definitelly go with one which has a clutch mechanism. It does work wonders.
crank: You'll most probably be able to use your current SLX crankset, but I'm not 100% sure on that. There is a possibility that you'll need to do some research and play around with spacers in order to have the perfect chainline so all cogs of the cassette are working well.
chain: If you go 1x9 get a 9sp chain. If you go 1x10 get a 10sp chain.


What is the significance of tire minimum pressure?

The minimum pressure is an estimate that will most probably work for the majority of people in generic riding conditions. Not going below the minimum pressure may prevent:

loss of control due to insufficient traction
pinch flats
burped air in case of tubeless
tyre unseating
rim bending on harsh hits
tyre carcass premature wear
rotation of the tyre/tube combo within the rim (can cause tube valve failure)

Of course, that number just an estimate. An aggressive rider, a heavy rider, or a really rough terrain may require higher than the minimum suggested values.


What Gates Carbon Drive parts should I upgrade?

Hard to give a good definitive answer to this. It's impossible to predict of replacing one or both sprockets and the belt will solve the rubbling and squeaking problem, although it's possible that upgrading to the newer type Gates belt would help (presumably they have changed the design because it was better).

If the rear sprocket retaining ring comes loose, something is probably worn badly, probably by riding when the ring came loose the first time.

The retaining ring really needs to be tightened to the proper torque specification with a torque wrench, which is may be way more than you are estimating.

If the sprocket spines are damaged the hub splines may be damaged too. I'd evaluate the hub before deciding how to proceed.


Have multi-speed non-freewheeling bikes ever been common?

I read somewhere about a three-speed  internal fixed rear hub, the Sturmey-Archer ASC (hmm, here maybe?; now replaced by the Sturmey-Archer S3X), and people were complaining that it had poor reliability. Obviously if something is not used in a big cycling sport (and has access to its R&D budgets), it has little chances for a wider market effort.


Can I use a Presta tube in a Schrader rim?

As you mentioned, one of the primary differences between a Presta and Schrader valves are the diameters--with Schrader valves being slightly larger--and therefore the valve holes on bicycle rims are drilled to suit one size or another.

Your foremost concern with using a Presta valve in a rim drilled for a Shrader valve shouldn't be 'movement' of the valve stem, as geoffc suggested, but rather a 'hernia' of the tube through the excess space at high pressure, leading to a blowout.

Most mountain bike tires sit at a low pressure, therefore you will probably get away with it, however, there is a very inexpensive adapter, sometimes called a 'valve grommet', which is made out of rubber or metal and serves to make the valve hole small enough for a Presta valve to fit snugly. It will also not come loose under high pressure, unlike geoffc's 'old tire' solution.


How do I identify the manufacturing year of a Surly frame?

From Surly themselves:
"What year was my frame built?

You know that serial number on the underside of your bottom bracket? No?! Ok, so flip your bike over and take a look closely at the bottom bracket shell (the cylinder at the bottom of the frame around which your crank rotates). There will be a code stamped into the shell starting with the letter "M". Sometimes this stamp has a bunch of paint that has collected in it but look closely, it is there, I promise. The following number after the M signifies the last digit(s) of the production year of your frame. So, for instance, M2598144 was made in 2002, M8128666 was made in 2008 and M10034269 was made in 2010. Now write down the serial number and keep it somewhere you can find it in case your bike gets stolen. This might be the only identifiable mark on your frame if it comes back to you!"


Shimano chainring compatibility (7400 vs. 7700)?

tl;dr

yes it will work, as long you use a 7700 inner chain ring. Otherwise you might encounter some skating due to the smaller 9-speed chain.

  "9-speed" Chainrings
  When the move from 8- to 9-speed took place, starting with 1997 Dura-Ace, a very slight change in chainring design occurred. Shimano was concerned about the potential for the chain to "skate" over the teeth of the small chainring.

  "Skating" occurs when a narrow chain is used on a crankset intended for a somewhat wider chain. In downshifting, instead of the chain meshing properly with the teeth of the inner chainring, the side-plates of the chain can ride along the tips of the teeth of the small ring, causing a momentary "freewheeling" forward. If you are foolish enough to downshift the front while standing up, this skating could conceivably cause you to crash.

  The difference between "9-speed" cranksets and older models is only in the inner chainring. The teeth on a "9-speed" inner ring are slightly displaced to the right to better accommodate the slightly narrower chain.

  Shimano will tell you you need to replace the inner ring when converting an older bike to 9-speed. Their lawyers say that covers them if you're clumsy enough to hurt yourself due to "skating" and, besides, they make a nice profit selling the chainrings.

  My advice is to not worry about this, and not to routinely replace the inner ring when upgrading to 9-speed. This type of "skating" is very rare, and mostly only happens if you're in top gear front and rear, then decide to downshift the front before downshifting the rear. There's no situation where this is a rational shifting sequence anyway.

Source: https://sheldonbrown.com/dura-ace.html#chainrings

Sidenote

Skating can also happen when you don't properly mount the inner chain ring. Since the tooth are not exactly in the middle, mounting the rings in the wrong way will cause additional spacing between the outer and the inner chain ring. This spacing is enough for the chain to slip between them.
https://www.landrys.com/images/library/large/shimano-deore-xt-m8000-11-speed-inner-chainring-198501-1-11-1.jpg


Here's my 90's bike - the main period features are

Earlier alloy construction, with fatness in the downtube.
Group set, Shimano RSX and exage brakes.  The RSX brifters lack trim support, so badly set up transmission makes a takka-takka-takka sound when in bad combinations.  So 90s.
Too new for sissy brake levers, too old for cyclocross interrupter brake levers
Seat post diameter of 26.2 mm (because 25.4 mm was too small)
No frame pump mounts - they're 80s.

Unsure -

This bike still has a quill stem and a threaded fork, which would have been old-school even at the time.
Pedals - the period originals weren't with it, but Look clipless would be right.  Platforms are probably okay too, but SPD would be seen as too much MTB.
Seat - this one was probably a replacement.
Rear wheel cutout - this bike looks a little tracky/tri because of how the rear wheel tucks into a cutout in the seat tube.  This is not a 90s thing, its an overall design thing.
FD connector - this one has a braize-on mech rather than a band-on one, due to the cutout.  Is this a 90s styling?  I don't know.

Please make comments to refine this answer.

EDIT I think  @ebrohman may have identified some of the defining style characteristics of a 90's bike.

Ugly - case in point
Minimalist - nothing that's not needed for going fast
Materials - There's nothing wrong with a good steel frame, but by the 90s steel was the cheaper end of the market.  Aluminium alloy, and titanium had their blips, and right at the end of the 90s is when carbon was coming in.
Unconventional - The standard diamond frame was pretty much defined, so new materials and the new possibilities then became available.  Consider my bike's brutal downtube, which lead on towards hydroforming of aluminium we see in today's MTBs.


Consequences of under-tight cassette ring?

Assuming your cassette and freehub body are conventional, the cassette sits on a series of splines, and would be free to slide left/right if there were no locknut in the way.
Since the hole in the cassette will be larger than the diameter of the freehub body, a missing or loose lockring will allow the cassette to twist out of the vertical plane parallel with the rim.  Effectively this will vary the horizontal position of the teeth over each wheel rotation, more noticeably on the bigger cogs.
However as long as the lockring is done up sufficiently to not back itself out and also tight enough to stop the cassette moving relative to the freehub body, you'll be fine.

I've serviced bikes where the lockring has needed a cheater bar to undo, and others where the lockring was not even finger-tight.   These latter ones tended to have poor shifting and/or damage to the freehub body's splines.  Since finger-tight is under 3 Nm  ( okay 0.1~0.3 Nm or 1.7~2.6 Nm depending on what study you're comparing)  then 24 Nm from your torque wrench plus a yank more with a spanner should be close enough.
In full disclosure, I've never used a torque wrench when securing a cassette lockring (new or reused) and I've never had one come off or fail.  You develop a feel for a pressure that is tight enough for this application.

https://www.ors.org/Transactions/59/PS2--085/1535.html tests .1 to .3 Nm
https://en.wiktionary.org/wiki/finger_tight says 1.7~2.6 Nm


In the menu that shows the paired sensors delete the sensor you want to remove. 510 will ask for a confirmation. Then re-pair the sensor. It may help to remove the battery from the sensor and putting it back after a minute.


Can I upgrade my Specialized Epic Comp 29er 2x10 to a 1x11?

Yes, it can be done, but you should consider what the cost of the components and  tools or paying for installation would be vs a whole new bike.

You will indeed need a new crank, cassette, rear shifter and chain. May as well replace cables and housings at the same time.

If you have and will stay with Shimano, you might be able re-use the rear derailleur, as Shimano MTB 10 and 11 speeds use the same cable pull ratio, I believe. You just need to check that the derailleur can accommodate the largest sprocket size you will be using.

Unlike road systems, 11 speed MTB cassettes fit on 10 speed wheel freehubs as the largest sprockets can overhang the drive side flange and sprockets a little.


Please identify a bike that is like a cross trainer

Sounds like an Eliptigo, as in  https://gearjunkie.com/elliptigo-stand-racing-bike.  They're intended to duplicate the exercise of running, but without the impacts of hitting the ground.

There isn't really a generic name for them, other than the class of "Funny Bikes" or possibly an "Exercise Bike"


Is there a way to convert the Park PCS-12 to PCS-10?

You're not going to be able to buy just the floor stand without the clamp unless you chance to buy one at a yard sale or on ebay, you might be able to contact Park Tool and ask them if they can send you just the floor stand without the clamp as a replacement part, but I doubt it for that particular stand.

My advice would be to just buy the new stand, amazon sells them for $90 less than their listed price. And you can get them for even cheaper than that on ebay. Then you can keep you bench mount for spare parts or just leave it where it is and have two stands.

You could try building a floor stand out of chain link fence parts depending on the size of post you need to fit the clamp. The cheapest solution would probably be to buy one post (or borrow one from a local school) and a floor flange, and either bolt it to your garage floor (permanent) or to a big piece of thick plywood (which will eventually break). I don't recommend looking at getting piece of plate steel like the PRS Deluxe stands have, because I've looked into it before and the size plate you's want would cost almost as much as a new PCS stand would. If you can get anything free by chance or from a junker/someone you know then that's a bonus.

But like I said, I think you'd be better of just to buy a new stand.


Headest: replace bearings or entire headset

You may not be able to see it, but it's pretty likely the races are damaged at this point.

One trick I've had luck with over the years is to replace the caged bearings with loose bearings. If that doesn't work, you can try using the next size up bearing. Both these tricks move the bearing contacts to different spots and can help a lot with indexing.

See Sheldon's page for more headset maintenance tricks

http://sheldonbrown.com/headsets.html

Loose bearings are pretty cheap and a whole lot easier than replacing the headset.
You can get a bag of 25 bearings for $5. Worth trying IMHO.


Please identify this vintage bike - peculiar frame

The three stars are the logo for "Malvern Star" which is an Australian brand that has been operating since 1902.

https://en.wikipedia.org/wiki/Malvern_Star

http://www.malvernstar.com.au/


Slight wobble/"drift" in chain due to crankset?

The amount of wobble shown in the video is fairly typical, for better or for worse, which is not to say it's a good thing or that the FD adjustment can necessarily be free of rub in all combinations and under variable load with it. You don't have to worry about this getting worse if you leave it alone.

For what it's worth, you can multiply your "AA AB BB BA" set by four, because the rotational position that a crank is mounted on a spindle determines how bad the total wobble is, and making things truly as close to perfect as obtainable requires you to test all of them. I don't recommend actually doing this in most cases, but it is true that one position will be the best, possibly to an extent that matters.

The nature of runout in a square BB spindle is that the mounting orientation 180 degrees different will distort the chainring the same amount the other direction, meaning that one orientation's error might stack with any imprecision in the crank in a way that maximizes the effect, but mount it the opposite way and the two could cancel each other out and look great.

For cranks with rings mounted on different sets of bolt holes, i.e. most triples but not most doubles, you can observe whether all the rings are moving in unison to draw inferences about whether a given bit of distortion is coming from the spindle or the crank. And of course, even on a double, you can compare what's happening between the two rings to infer whether you're looking at error in the spider tabs or the rings themselves.

Spider tabs can also be trued. Before doing so it's important to do some kind of testing or measuring to make sure it's not the BB or chainrings that are causing your problems.


Using wrong speed/size cassette on trainer

As you suspect, you cannot use the 8 speed cassette with either bike. The indexing will be completely wrong.

8, 9 and 10 speed cassettes use the same freehub body so you can put a 10 speed cassette on the wheel. The sprocket spacing on the 11 speed cassette is different from the 10 speed, so that isn't going to work, at least not very well. Maybe you could get a few gears to work.

If your derailleur capacity and chain length don't allow the use of a 11-28 cassette, you will be OK as long as you stay off the sprockets that are too large. If you can't use a 11-28 cassette, why fit one? I guess you happen to have a spare lying around?


Can a (20*1.35) tire fit on my rim that has a (20*2.125) tire on it now?

Width compatibility is a matter of rim width, but according to the oft-cited table there's unlikely to be a rim that's particularly good for both 1.35" (35mm) and 2.125" (54 mm).  This is a big change, so unless your rim is on the narrow side for the tyre that's on there at the moment you might have trouble.  So in your case you really need to measure the inner rim width before going shopping.


The inner cable is very rusty. I would think that the cable friction is so great that the spring of the brake cannot pull back against it. Maybe at the other end of the cable, something has popped out of place, you can inspect the other end and see if this is the case.
Ultimately, the solution is going to be to fit, or to have fitted, new cables and the brakes setting up again to work well. If that cable condition is indicative of the rest of the bike, a good service is due which will make it nicer and safer to ride.


Is it safe to use aluminium seatpost adapter (27.2mm to 31.6mm) for a carbon frame?

80 mm length should be long enough to provide stable and good grip. Do make sure to use carbon mounting paste, of course, wiping any traces of grease (if they exist) off the adapter and the seatpost. If the seatpost stick long above the frame and if it's an off road bike, I might consider it a tad bit risky move. Otherwise, you should be fine.

And, like the previous poster said, to occasionally check for traces of galvanic corrosion. You don't want the seatpost stuck to the frame.


Why would a salty damp road be slipperier than the same road just damp?

It turns out there's actually some rather interesting science behind friction in the presence of water and salt.  Various model systems demonstrate that salt solutions really are better lubricants than plain (distilled) water between rubber and other materials, and by enough to matter.
Unfortunately little if any work has been done on the friction between real rubber and real wet roads in the presence of salt.  But there has been some work on more idealised systems.  One of the clearest results is from Experiments on the Lubrication of Raw Natural Rubber E.L. Ong and A.D. Roberts J. nat. Rubb. Res,, 1(1), 41-50 (1986).  Table 5 (below) is particularly interesting. Betwen raw natural rubber and Perspex the coefficient of friction reduced from 4.1 when dry, to 2.6 when wet and 1.5 when wet with salt solution.  A similar trend was observed for rubber-on-rubber friction. In other words in this system, in salt water there's about 60% of the grip compared to clean water. Fom the caption, "Stickslip motion tended to occur and maximum friction coefficients are quoted" (my emphasis). It's not clear whether this is true for all cases or just the salt solutions referred to in the preceeding sentence.

My journal access doesn't extend to reference 3 from this paper, Rubber friction in aqueous solutions containing ions, T.P.Mortimer & K.C.Ludema, Wear Volume 28, Issue 2, May 1974, Pages 197-206.  But the abstract of this latter paper states:

In the case of water lubrication of black rubber at slow speeds and
low pressures the lubricating ability of water is shown to be enhanced
by addition of electrolytes to the water. It is thought that negative
ions from the electrolytic solution collect on each sliding surface,
repel each other and prevent the close approach of two sliding
surfaces. Thus a thicker water film exists between the sliding
surfaces than if the ion layers did not exist. The thicker film
results in a reduced viscous drag force, lower than can be accounted
for by conventional hydrodynamics.

The ~40% reduction in friction from the table quoted above is enough to negate a reasonable safety margin when it comes to grip.  Applying this to my case I suspect an element of bad luck came into play too: That some tiny slip became unrecoverable because the overall friction was too lowThis would be especially the case as dynamic (sliding) friction is expected to be lower than rolling friction, thus extra grip is needed to recover a skid compared to avoiding it in the first place.
Further Reading:

Rubber Friction in Aqueous Solutions Containing Ions
Friction of rubber on ice in the presence of salt
DLVO and hydration forces between mica surfaces in Li+, Na+, K+, and Cs+ electrolyte solutions: A correlation of double-layer and hydration forces with surface cation exchange properties
Effect of aqueous cations on friction between rubber and glass


It does sound like a tandem is a good option for you and your wife. A trike for her (many recumbents are trikes) might solve the balance problem, but not the speed issue.

There are definitely folding tandems out there.  Might even be able to fold up and stick in the back seat.

The "simplest" way to get what you want is an an [S&S Coupled bike with a [single split in front](http://www.sandsmachine.com/tandem.htm#single split in front).  That's a bike that doesn't "fold", but does split into two pieces (or 3). If it splits in front you should be able to put it on a car bike rack and won't have to mess with taking a chain off. It's possible to retrofit many non-aluminum bikes into a folding/travel bike this way.

I believe usually people get an S&S coupled tandem so they can fly with the tandem and not pay outrageous shipping costs. Since you're more interested in getting a bike onto a bike rack on the back of your car you should have an easier time finding options.

So, the good news: yes, options exist. The bad news: they're custom or semi-custom and generally expensive.

Take into account that tandems can be hard to fit properly unless you're the "right" size difference.

Your best bet is probably locating a couple framebuilders near you and talking to them about your needs.  But look around at a few of these links to see what some options are:

Folding Tandems from Bike Friday -- folds up small enough to fit in back seat. Custom. The "example" build prices that look like a fast road bike tandem setups seem to start around $3000 USD
Zinn Cycles Tandems -- I think the Titanium S&S coupled tandem is a model I saw at a big group ride. "$12,000 and up", but the steel travel tandem could be as little as $8000.
Calfee seems to have carbon road tandems with S&S couplings available for $8000
S&S Coupling US Framebuilder List (look on their site through the photo gallery and retailer list, too. And at the tandem page. Oh, and the [tandem retrofit photo gallery](http://www.sandsmachine.com/#Tandem Retrofits))

(If I could afford it and had those needs, I'd talk to my local framebuilder since he's on the S&S framebuilder list and does a bit of tandem stuff even if he doesn't list prices for them yet. But framebuilders closer to you are probably a better option than one in my town.)


Should I put grease under the lockring on my cassette?

If the bearings are sealed (so dirt can't get into the bearing), and there isn't an interface (two surfaces rubbing together), than lube is probably not needed.  Adding lube may actually create a dirt-trap as more dirt sticks rather than just getting in there and falling back out.

The threads, certainly.  Packing in behind the lock ring?  Not so much.


Finding the right size wheel for a electric bike kit

Most ebike kits with hub motors are sized for 26" mountain bike tires and not the larger 700c road/hybrid tire. There are numerous reasons for this:

the smaller the wheel the more torque it can handle as well as deliver
*conversely, the larger the wheel the larger the hub motor has to be (adding to weight) or it has to be a geared hub motor, adding to complexity. In either case, hub motors for larger wheels are more expensive.
mountain bike frames are built more solidly and can take the extra weight and abuse
contemporary consumers tend to prefer the mountain bike styling and as a result cheap MTB frames are much more commonly available than 700c frames
if you only want to stock one SKU you'll stick with the most common one.  It doesn't hurt that a 26" wheel is cheaper to ship than a 700c one

As a result, it's much harder to find an off the shelf 700c rimmed hub motor compared to a 26" one. In most cases, you have to get a hand laced 700c rim on a hub motor. This adds cost and expense and is non-optimal as the motor was likely wound for a smaller wheel and will deliver weaker performance in a 700c.

Most end users  give up and instead get a cheap 26" mountain bike for their donor bike rather than using their 700c bike.

And if you have to ask: no, it's not possible to put a 26" wheel in a 700c frame -- not without considerable pain and expense. Seriously, just get a 26" BSO frame or be prepared to pay more for a boutique 700c hub motor.

Ps. If you're intent on keeping the 700c frame, a better option may be to use a bottom bracket (also known as mid-drive) motor. Bafang is the most common vendor of aftermarket BB motors  and if you google (bafang bottom bracket) you'll find vendors. However, they do tend to be more expensive than hub motors.


combining friction shifting with indexed components

Yeah, the only real problem is maintaining fine enough control of the motion, both in actively moving the lever, and in avoiding "creep" between shifts.  In part it comes down to how much fine muscle control you have, and in part it has to do with the quality of the shifter and how it's mounted.


Drop the chain and try to rotate cranks. If "skip" feels then I would look into BB. If not, then pretty much sounds like kink in the chain which is very possible on very new or very old chains.

Very new chains can be over-pressurised while installing and therefore one link connection is just not flexible enough which makes it "skip" when going through the derailer. Old chains have rust and dirt problem which causes same problem.


How can I cycle in winter while not being able to change work clothes?

I've had success wearing legwarmers under trousers during winter.

The main advantage is at the far end you can either wiggle them down while standing, or drop your pants in the toilet cubicle and shove them down around your ankles for comfort.

This works well with overshoes, in combination with a decent jacket and gloves.  I also wear a neck buff and/or helmet liner.

Try sitting nearer the window or door if you need a cooler breeze.


Reposition pedal on a fixed gear (fixie)

Have you learned how to skid the rear wheel yet?  As you are coming into the stop you can give a few hop/skids to re-position your pedals before you come to a stop.  After a while you get good at judging distances so you can nail getting the dominant foot forward at each stop.