Why can't I ride my city type (folding) bike uphill?

Folding bikes have a very limited gear range because they usually have only a rear derailleur. From the manufacturer's website, your bike has:

20" wheels with 20x1.5 tires
52T chainwheel
14 - 28T rear cassette

Running this through a gear-inch calculator shows that your highest gearing for going fast is 66 gear inches and lowest gearing for going up hill is 33".  Your total range is 33-66" or 2x.

Link: What are gear-inches?

In comparison, a bog-standard 700c hybrid bike at the bike shop with 3x9 speeds is going to have around 24" on the low end and 116" on the high end -- a range of over 4.8x. It's going to be both much easier going uphill on the hybrid (24" versus your 33") as well as much faster downhill and in the straightaways (116" vs. your 66"). Standard (big) bikes also have full length cranks - sometimes our folding bikes come with kid-size cranks which also reduces leverage uphills.

You can do some things to improve the overall spread and to reduce the gearing to make it easier to go uphill. You could replace the 14-28T 7-speed cassette with a 11-32T which has a larger spread so it would help a bit going downhill as well as uphill. In addition, you could reduce the size of your chainwheel from 52T to something like 48T to again help with the hills.  I'd recommend against an 11T sprocket on a 20" wheel as there will be a lot of wear on the teeth and so you'll chew up your chain and sprocket really quickly.

With a more reasonable 13-34T cassette and 48T chainwheel, for example you'd get 27.5" - 85" gear inches which should be enough for many purposes.

You're limited in modding by the capacity of your rear derailleur -- and if you swap it out with a long cage, it may drag on the ground on corners. The standard Shimano Tourney 7-speed on your bike seems to be ok - most models in that series are specced for 11-34T capacity. I should also note though that some sprocket/chainwheel/chain lengths may no longer allow the bike to fold smoothly or result in the chain derailing when you fold, so you'll need to fiddle a bit.

If it were my bike, I'd look at the terrain and make the decision. For my Brompton, for example, I got a smaller chainwheel as I live in a hilly neighborhood and needed the reduction in gear inches and don't mind my top-speed being limited. I had to take a few links out of the chain but it still folds ok.

Finally, I should note that even at the same gearing it's harder to go uphill with a small-wheel folding bicycle than it is a full-size bicycle. Our tires are smaller so they have less stability (less gyroscopic effect/leverage); our cranks are shorter so we have less leverage; and our steering is squirrelly so it's harder to go in a straight line.


How to tell if a chain is Bicycle Chain or something else?

From a little research it would appear most Mini Moto Bikes & Quads up to 50cc mostly use a 25H or 25E chain.
They vary in price depending on retailer but most seem quite easy to buy being a popular item. As we know very little else regarding main drive dimensions (cog / gearing) apart from the fact it should only consist of a main drive gear and a smaller one on the rear axle.

All I can do is attach a chart of the most likely chains and the OP can hopefully work out what chain is required according to the dimensions on the gearing.


Road bike fitting: Fit calculator results look slightly different with the bike I am planning to purchase

The frame you are planning to purchase has a sloping top tube. This means that the seat tube is shorter than what it would be if the top tube was horizontal, and you simply use longer seat post to compensate.

On the other hand, the results from Competitive Cyclist calculator does not have any numbers for stack, or height measured from bottom bracket to top of headset. With horizontal top tube this is not a issue, because it is directly related to seat tube length, but with sloping top tube you have to calculate it from bottom bracket drop and head tube length. Since the fit calculator recommends an unusually tall frame, the head tube is probably fine, and if the handlebars are too low for you, it is easier to raise than to lower them.


Do brake cables become more elastic with time?

Cables will stretch over time, but they won't become elastic. They're made of twisted strands of metal, and metal isn't generally known for its elasticity.

This sounds to me like your brake pads are shot. When they become spongy and glazed, you can squeeze your brake lever quite far and feel like little pressure is being applied. Get thee to a bikeshoppery.


In practical terms, how often do you have to adjust the belt tension of a belt drive bicycle?

I have been riding a Gates CDC (not Centertrack) belt drive for almost a year now.  Gates claims that tension adjustments are not necessary over the lifetime of the belt drive.  My experience does not support this claim.

One of Gates' claims is that the belt does not stretch enough to warrant tension adjustment after a break-in period, as you would on a brake or shifter cable.  I found this to be true.

However, I have noticed that the tension of the belt changes significantly with temperature (and possibly humidity, though I don't have enough data to test that hypothesis).  I have ridden my bike in various weather conditions and temperatures ranging from over 90℉/32°C to under 0℉/-17°C. I use the Gates iPhone app to check my belt's tension.  I have noticed that, if the belt is tensioned properly at about room temperature, then the tension in the belt decreases below the recommended tension range when the ambient temperature drops below about 20℉/-6°C.  I have noticed problems with the belt drive when tension is too high or too low, including excessive noise, skipping, and misalignment leading to dropping the belt from the sprockets.  Therefore, I found it necessary to retension the belt slightly in the beginning of the winter and again at the end of winter.

I'm not certain yet if the weather-related change in tension is caused by frame shrinkage (I suspect this is the case - my frame is aluminium) or by another factor.


The first result on google is http://www.shimano-sportcamera.com/us/application.php - if you click the little youtube video, it shows how to integrate Ant+ sensors and the video.


Well, 26 will feel a whole lot better than your current 23. You can get away with lower air pressure because of the larger volume supporting your weight. Lower pressure means smoother ride. Of course two tires of the same size can feel very different because of the quality of the casing and rubber. For commuting, I would say get as big as you can fit, which is hard to know without seeing the bike. Many modern road bikes can fit up to 28mm, but you'll have to look and see. There are three potential spots to look at: fork, rear brake bridge, and rear chainstays. If you can measure the gap between your current tire and each of those three spots, you can get a very rough idea of how much bigger you can go.

Your rims should be fine with anything at least up to 32mm if not more. They can accommodate a fairly wide range of tire widths. As the tire gets wider, it will tend to make more of a lightbulb-type shape which can be less stable, but that usually isn't bad until you get extreme in the differences.


Can I use a SRAM Powerlink on a Shimano chain

As long as it's a 9-speed power-link, you can. I have chains in all bikes connected this way and find it most convenient method. The one made by SRAM is also the easiest to open.


Presta valves are fairly fragile things. It's easy to bend the stem once it's unscrewed. They work by the tube pressure being higher than the atmospheric pressure. This causes the valve to be forced closed. It is not until you either loosen (unscrew) the valve and depress the stem or place a pump on it and increase the pressure above the valve until it is overwhelmed and allows air in.

Point is, you can leave the valve "untightened" and air won't escape. The valve mechanism failed because for some reason it did not return to a closed position completely and leaked out. Then when you tried to top off the tire again it was further stuck Two best guesses:

1) You had a run of bad tubes. Welcome to road cycling. Things are more fragile. This is my first choice. Buy a different brand and see what happens.

2) Schrader valves are more durable and forgiving of rougher treatment. Perhaps you were use to them and when you topped off the presta tubes you bent the valve core and it wouldn't fully return to sealed.

Don't give up. I've had bad tubes before.

And one last thing: If you are a valve bender (like myself) I found the cure. Silca and SKS both make a chuck that doesn't need to make contact with the valve core. It uses the pressure from the pump to overcome the resistance of the valve core. Here is the SKS version, currently on sale at Saint John Cycles. You just push it on and pump. Couldn't be easier or more effective. Good only for presta though.


An odd possibility, but it happened to me... does your foldie have a kickstand? If so, any chance that your crank is hitting it while you pedal?

Fix for me, once I figured out the problem, was obvious and simple: put kickstand up, push it in toward frame, tighten it down with hex wrench.


V-brake noodle broken: replace immediately? With what?

A noodle is totally cheap, and you should replace this immediately even if the brake appears to be working.   Dragging the inner around a sharp bend will fray the strands, leading to a sudden failure and a lack of front brake when it snaps.

Noodles come in two different bend radius.

90 degrees, often used on the rear brake
135 degrees, which is most common on the front brake.

Your folding bike might use either, it looks like a 90 degree one to me.

Note, you should change the inner brake cable at the same time.  Depending on condition, its also a good time to replace the outer if anything is wrong with it, like cracks or bends or rust.


Likely a a better rider would have stayed on, and there is work to do on you technique, but your suspension should not miss behaving like that. Your comment about rebound settings strongly suggests to me that will the route cause of the problem.

Sag is at the very best a starting point. Once you have the sag correct, you have a 'stake in the ground' to start tuning the suspension. The other settings are perfect for the average rider. The average rider has 2.5 kids, 13 feet a white picket fence and 1.2 dogs, my guess is you are not average :).

Have a look at this video. MTB Suspension Setup - How To Get It Dialed In 10-Minutes

The sag sets the amount of support the suspension offers - too little and you bottom out, too much and you don't get to use all the travel and don't get the benefit of it. Rebound sets the rate the suspension comes back after being compressed. Too fast rebound and you experience what you have had happen - the bike 'bounces' and you loose control (on the front the wheel lifts and it gets sketchy, on the back, you get flicked up, which with weight back and too straight legs could be turned into forward surge ). Too slow rebound and the shock /fork has not recovered before the next bump. After a few bumps, you have run out of travel.

The idea is get the rebound of the front and back balanced so the whole bike lifts evenly. You also need to get it so it rebounds just fast enough to recover, without being so fast it lifts wheels off the ground.

If anything, set rebound slower than ideal, and speed it up until you feel its too fast, then wind it back a notch or two.


Looks like a pair of Forté Carve pedals. Forté is a house brand of Performance Bicycles. I checked their website, but this particular model of pedal doesn't appear to be available any longer.

(photo from College Tri blog)

Here's another photo that shows the "CARVE" logo with the stylyized "V" engraved into the cross piece that matches the letters you found on your pedals:

(photo from mtbr.com)


If you go for a ride in the morning, your body's main source of energy is glycogen stored in your leg muscles, which came from the food you ate for dinner the night before. (There is also liver glycogen, and you can burn fat, but it's a slower process.) For most people, muscle glycogen is sufficient for about 2 hours of continuous, strenuous exercise. Once glycogen is stored in a particular muscle, such as a leg muscle, it can't be taken out of that muscle for use anywhere else. (Liver glycogen can be donated to other parts of the body that need it.) This two hours is if you're really putting out your maximum effort the whole time. Most cycling isn't actually that continuously intense over long periods of time -- the bike is after all a fancy device for improving your body's efficiency. In many cases you may be able to cycle for much longer, like 4 hours or more, without running out of glycogen.
So in terms of energy available to perform muscle contractions, typically it's not really necessary to eat anything unless your ride is very long. However, it's possible to start feeling hungry even when your legs still have plenty of glycogen. Being hungry is going to make your ride unpleasant, and may have the effect of decreasing performance, since fatigue is a complicated phenomenon mediated by non-conscious parts of the central nervous system. So basically it's just what you would think based on common sense: if you're hungry, eat.
At very long distances, where muscle glycogen is in danger of getting depleted, your body will try to switch over to burning fat, but that's slow, so you'll start to feel like you're bonking. In this situation it becomes important not just to avoid hunger but to provide your body with some energy that it has some hope of digesting fast enough that it can be used for pushing the pedals. If you anticipate this kind of long ride, then you can basically eat as many carbs as possible, starting even before the ride, in hopes of being able to use the energy. However, your body doesn't do a very good job of digesting food while you're exercising, and digestion takes time. That's why people often take small amounts of carbs, spread out over time.
Different people also differ in their ability to handle food while exercising strenuously. Some people barf if they try to do it. Do whatever works for you.
The main differences between a GU and some other carb-based food like a granola bar are that the GU doesn't require chewing, and it's also conveniently packaged for use while running or riding. Basically a GU is like cake frosting (or actually maltodextrose) in a convenient package.
There seems to be pretty solid science behind the concept of carbo-loading, i.e., eating lots of carbs in the day or days before the activity. Studies have shown it increases performance by pretty hefty amounts. Probably it just helps to top off your glycogen supplies. Having that energy already digested and available as glycogen is a big win. Eating during the activity is at best a minor benefit in comparison.
And BTW please don't be like a lot of the mountain bikers on my local trail system and leave your GU wrappers on the trail!


My back wheel will no longer spin freely

I am pretty sure the issue comes from your disc brake.
Check the brake pads first : there must be something wrong here because you say it was worse after you removed and put the wheel back.

I guess your brakes are hydraulic : sometimes when you store your bike in a humid place for a long time, the braking fluid will kind of "dilate", resulting in less space between the two pads, hence rubbing on the disk even if you don't press the lever.

Another test you could do is removing the caliper : if the wheel spins freely, that confirms my theory.

In that case, you need to push the pistons back to their initial position (using something to pry them apart, without damaging the pads). If you cannot, you might need to remove some fluid from the hose (there should be a small screw at the lever), but be careful not let some air go in the hose.


Will this power2max power meter be compatible with Cannondale Synapse?

Yes, you can install a Type S - Rotor 3D24 on your Synapse using the following adapter:

https://www.c-bear.com/en/products/bb30a-cannondale-synapse

You also have the option of Type S - FSA MegaExo (Gossamer or K-Force Light) and Type S - FSA BB386EVO (Gossamer or K-Force Light). Please have a look at the following chart from FSA:

http://www.fullspeedahead.com/wp-content/uploads/2014/04/POSTER-BB-2014-ROAD-A234.pdf

If you have any other question, please feel fre to ask !

Andrés
power2max Team


Going out on a limb, my guess is that the chain is too tight.

I've seen (heard) this issue on many bikes like this. On about 98% of big box store bicycles are sold with all the bearings and the chain too tight and the tires too low on air.

How tight should it be?:

  The chain slack on a bicycle ... is quite critical, and is regulated by moving the rear axle back and forth in the forkends. ... The chain should be tight as it can be without binding. If the chain is too loose, it can fall off

Later in the article:

  When adjusting the chain, you need to be able to turn the cranks. With a fixed gear or coaster brake, the rear wheel has to be off the ground. Keep your fingers away from the sprockets: the momentum of the rear wheel can crush a finger caught between a sprocket and the chain.
  Sheldon Brown, Minimizing Chain Slack

Assuming the chain is too tight you'll want to loosen the chain just enough to make the popping stop.

Loosen the chain side axle nut and push the tire to the side so that the chain is gains a little slack.
Snug the chain side axle nut up enough to hold (it does not have to be fully tightened yet) and test chain tension by pedaling (watch your fingers!) and listen for popping.

If the popping is gone tighten the chain side axle nut fully. If not repeat steps 1 and 2

After adjusting chain tension the wheel may not be in the center of the frame.

Loosen the non-chain side axle nut and center the wheel in the frame.
Tighten the non-chain side axle nut fully.

If the chain is not the cause of the popping sound no amount of loosening will make the popping go away.
What ever it turns out to be riding enjoyment and bike lifespan will be maximized if you have someone with some knowledge of bikes check it over from end to end.


Can I buy an aluminum seatpost with a chromoly frame

There isn't a problem with putting an aluminum seatpost in a steel frame. It's a pretty common thing to do.

Make sure to grease the seatpost before putting it in, lest it get stuck. If it does get stuck, you could try ammonia or drano (sodium hydroxide) or chilling the thing (e.g. with a CO2 cartridge to unstick it). See this page for other stuck seatpost suggestions.

Also, make sure you have the right diameter seatpost. This can be done by checking the documentation for the frame, or using a seatpost measuring tool (which most bike shops should have), or a pair of vernier calipers.


Suggestion on buying a single speed 29er mountain bike

SE Stout is a single speed mountain bike that runs relatively cheap.

If you're confident in your ability to put it together properly, you can find them at bikesdirect for around 350.
http://www.bikesdirect.com/products/se/stout.htm

It's got tabs for disc brakes so you could upgrade in the future, but comes with V-Brakes stock.  I have a few friends who have these bikes and really like them.


My wheel tilts to the left (to the disc side) any solution

It is a normal effect with disc brakes, the major reason why most motorbikes have left and right  discs at the front. Braking on the left side only will cause a slight deformation of the left leg of the fork, pushing it backwards. The wheel follows.

I'd guess you have quick releases on your bike. If you do, try to tighten it a bit more. Through axles have been introduced to help better secure the wheel in the drop outs but also to stabilize the fork.


Maintenance/Upgrades for Gary Fisher Joshua MTB

My suggestion is in line with heltonbikers.Bring the bike to a local shop and have them look at it.A simple tune-up may be all that is needed.Many shops offer spring specials so call early to avoid delays.I am not sure why you assume you need to replace all these parts .My theory on upgrades is to wait until there is a need to replace a component.If a parts is functioning and meeting your needs why replace it?My guess is that if both were properly adjusted most people couldn't tell the difference between the alivio and deore line.If your shifters are beyond repair that is the time to upgrade.My fisher marlin disc came with alivio and I think they're a great shifter.They are 4 years old and still work great.


This could be coming from the bottom bracket, which will make noise when worn out and pedalling under load. One way to test this is to stand beside the bike, grab one crank in each hand and see if they can be rocked towards/away from the frame. There should be no play in this direction. This is described with pictures here.

If that's not the problem, then the following link has a rather comprehensive list of possible causes of bike noises.


Short answer based on the little information given I'd guess two larger panniers would be enough, especially if the tent and sleeping mat is strapped on top.  Watch out for the heel clearance, especially with the largest ones.

Long answer and rambling: The length of the trip doesn't matter as much as you'd might think.  It really depends on how much you'll going to pack.  The truth is that probably a beginner will back more than an experienced bicycler tourer because you have to figure out for yourself what items and luxuries you'd like and which ones aren't of value to you.

Make a list of the things you would like to take along.  Maybe get some feedback from experienced tourers and have them review and comment on your list.  Take their suggestion with a grain of salt, since it's really personal what one takes along.  Then judge from that how large of a panniers you need.  Don't over stuff them if possible.  Not only will it be harder to get your things out of the bags but you also need some room for food purchases during your trip.  Often people stop at a grocery just before the campsite to stock up on food for the night.

Don't carry water in you panniers.  Two or three water bottles in cages should be plenty.  You wan want to take a small water bladder along if you go through the occasional area where extra water is needed (i.e. campground where drinking water isn't available).

Ortlib and Arkel are some popular pannier bags but really any sturdy pannier bags will work.  Some people even mount kitty litter tubs as pannniers to their rack.  Ortlib bags are by default rain proved but they also don't have external pockets and aren't breathable.  Most other bags including the Arkle need a rain cover for rain. BTW, try choosing a color that improves your visibility (yellow or red instead of black).

A main thing to keep in mind is to balance the weight evenly between the sides.  If carrying much you can also mount a front rack.  This will also distribute the weight off your rear wheel.  The goal with front racks is to keep the center of gravity low.  So lowrider front racks are often preferred.

Some alternatives to pannier bags are trailers (single wheeled like the bob trailer or two wheeled child trailer), frame bag (especially popular with mountain bikers in conjunction with handle bar rolls when riding narrow trails), or just tying everything onto your rack.

[links are just for clarifications, not for endorsement]


How bad is this fire damaged alloy frame?

I've done a bit of aluminum anodizing which requires annealing (softening) of the metal. This happens at about 650F. You mentioned the drop bars being melted so I suspect the top tube is likely annealed and won't have the same stiffness as it's suppose to. It may flex more than it should and may cause other parts to flex more also.

The head tube bearings were also mentioned and should be checked. I also wouldn't trust the seat post.


Will Slick Tires Work for a Mountain Bike Ridden by a Heavier Rider?

Those tires should work just fine. Any of the MTB slick tires listed on that site would work well with your bike and current rims.

You can get too small a tire on too wide a rim, but it takes a much bigger jump than from 2" to 1.5 or so. There is a very conservative sizing guide on Sheldon Brown's bike pages.

Given your weight, I would try and find the largest size slick you can. Something like the Schwable Big Apple in a 2.0" format1 supports a maxim load of 275 lbs per wheel, but it's outside your price range, or from that page the Kenda K1029 Kwick Roller Sport 26 Inch Tire (50-559).

The last number is key to understanding tire sizes. You have 559mm rims, so just about any 559 tire will work with your bike. The 50 is the nominal width of the inflated tire in mm's. ( i.e. 50mm ~ 2 inches ).

1 Schwalbe has a sizing guide too.


I don't know where you want to start or finish, but here's some strava routes for central Durham to to central Carrboro

Red roads are more popular for cyclists, blue ones are less travelled, and white ones are rarely or never cycled.

Route between Durham, NC and Carrboro, NC?   This one is the most "popular" based on strava tracks, and is 22.8 km.

This path minimises elevation changes, so instead of 309 metres of vertical you only have 225 metres of climbs.

This is the most direct path but it appears to go down a main road, which may not be legal on a bike, in your area.

You can also find a number of strava segments in the area, using this link
https://www.strava.com/segments/explore#location/durham/type/cycling/min/0/max/5/surface/undefined/center/35.92059,-79.052797/zoom/14/map_type/terrain

Curiously, Google's suggestion is different again to any of these.


I found this article - Tykes and Bikes - Injuries Associated With Bicycle-Towed Child Trailers and Bicycle-Mounted Child Seats

The paper estimates the numbers of trailer-related injuries and the number of child seat injuries:

  there were an estimated 322 injuries associated with the use of a bicycle-towed trailer (95% CI, 158-486) and an estimated 2015 injuries related to the use of a bicycle-mounted child seat (95% CI, 988-3042).

The paper notes that there is some uncertainty around these statistics:

  The data indicate the incidence of injury associated with the use of either bicycle accessory was low. However, injuries related to use of bicycle-towed child trailers were much less common (estimated 322 vs 2015). We do not know if this is because there are fewer bicycle-towed child trailers, resulting in lower exposure, or if there is truly a lower risk of injury associated with bicycle-towed child trailers.


I disassembled the caliper and the ceramic pistons were both shattered. They were either shattered on arrival or this was from trying to put a bleed block in when the pistons were slightly out. This pushed the pistons into a slight angle. Then they shattered when squeezing the brakes.


Can a bmx hub support a 7 speed mountain bike freewheel?

You could do this by respacing a standard axle (as opposed to proprietary) 3/8" BMX hub. The freewheel thread is the same as long as the BMX hub doesn't take only metric or LHD freewheels. It's something a tinkerer might do for fun to make use of some rims. There are some issues that may hold it back from practicality:

Current standard 3/8" axle 48h BMX hubs are more or less garbage
parts. Almost by definition they only have 48h for looks at that
point, since real freestyle bikes use 14mm rear and race bikes never use
48h. There are probably pre-14mm hubs that are counterexamples, but I can't think of any that use standard axles.
The extra strength and durability of it being a 48h wheel would
be somewhat wasted given its vulnerability to bent axles, being a
freewheel hub.

Some BMX rear hubs have flange to flange distances that are significantly greater than the 57-58mm numbers usually found on 135mm MTB hubs. You'd want to avoid that, because making a derailer wheel out of one would give less lateral strength.


Does air leak out when you depress the valve?  If so, air can get in, too, and it's your pump, or at least how you're using the pump.  My old bike pump would act up like this when I pushed it onto the valve stem too far (presta valves).  Could be the case for you, too.


Commercially available sprung tyres/wheels?

Loopwheels makes bicycle wheels with springs in stead of spokes. They also had a successful Kickstarter, so it might be what you were thinking about. They do however still rely on normal tyres and rims, so can't be said to work without pneumatic tyres. Although I bet you can run a pretty high tyre preassure quite comfortably with these wheels.


Presuming it came out of the bike, probably oil from Hydraulic brakes. Although the link does not specify things in detail - A 2009 bike with Tora Rock shox and Deore components would almost certainly have had hydraulic brakes.

Check the brakes are working and not spongy. If in any doubt take it to the LBS for a check over - a leak from the shocks needs fixing but would not be the same seriousness as a leak from brakes.


How to repair a broken steel frame, at the rear drop out /chainstay location

Apparently Raleight Techniums are weird combination of aluminum and steel. Rear triangle of Techniums are steel (chro-moly, I'd wager) so they should be repairable.

Looking at the pictures of Technium rear dropouts, they seem to be cast pieces that are brazed to the rear triangle. If the joint between the dropout and seat/chain stay is broken, then the fix is matter of re-brazing the dropout. If the dropout itself has cracked, then it needs to be welded together.

In either case, you need to take the frame to shop that can handle frame repairs. To do it yourself, you'd need a workshop and either TIG welding machine or oxy-acetylene torch and brazing materials. Not a job to the faint hearted.

Full disclosure: I'm a amateur frame maker. I've made couple of lugged frames and fixed a broken frame by welding it, so I have some idea what I'm talking about.


Is there not enough shim on my suspension pivot?

It is very possible that during assembly, the pieces were missed.

Try to see if you can shift the seat-stay or chain-stay sideways on the pivot. If you can, you definitely need to find another bushing to fit in there.

If there is sideways play in that pivot, it will wear out prematurely. You'll also get all sorts of dirt and debris stuck in there, which will also wear out the pivot much quicker than if it were covered with a bushing.

Another thing you could do is go to a brick and mortar store that sells the same brand of bike and see if the bikes in the store are also missing them.


Converting old mountain bike to fixed gear

Single speed and a chain tensioner will work no problem
In general, fixed gear in these situations is not a good idea.
It could work if you use a half-link chain and choose your rear cog and front chainring so the size works perfect with the chainstay length. But this will fail  over time as the chain wears out and the fit becomes loose.
The issue with chain tensioners and fixed gear is that when you use a spring tensioner and apply forward pedalling pressure, there is no problem, but when you apply backwards pressure, the chain will becaulse loose and will most probably come off. When you stop the forward pressure, the chain will become tight at the bottom (yellow arrow on the picture) and loose at the top.

If you try a non spring tensioner, such as the DMR STS, the forces you generate are stronger than the bolts on the tensioner, so you will be constantly re-adjusting the tensioner.

In my experience, as I already tried this, you would have to fine a chain tensioner which works on the bottom of the chainstay when you pedal forward and one on the top when you put pressure backwards. And non spring tensioner just come loose very easily. I suggest you go down the single speed route and not the fixed gear route.
Good luck and well done for fixing up that frame.


Can I tell the inner diameter of my 1" head tube without removing the headset?

Probably not.
Knowing the manufacturer of your bike gives a clue but not always definitive.
One is the Italian size and more common. The other is Japanese.


Is it possible to add speeds to single-speed bike?

If you want a 27 speed bike then buy one.  It is not cheaper to add speeds to a single speed or fixie bike.  Lots of stuff is not compatible including axle spacing and real wheel.


Handlebars for an upright seated position

You can likely find bars the will fit, but keep in mind that you still want the bike to function which means moving over your shifters and brake levers. While you could probably do this as a DIY project, I'd really recommend going to a bike shop and at least getting some advice first.

The can help you select a bar that is the right diameter to fit with your current stem and talk you through issues like re-cabling (longer bars probably mean longer cables) and where/how to mount shifters and brake levers. You might end up wanting to change brake levers to a different type depending on bars.

Don't forget the you still need to be able to get on and handle the bike. You will be doing some strange things with the center of rotation for the bars. At low speed (...i.e. the speed cruiser bikes that normally have these bars), this is probably not an issue. But you get up to high speed on a decent and you might find yourself in trouble. Start slow and see how it handles.

Happy riding.


Repair service specifically for bike commuters?

You don't need such a repair service.  There is a different, more practical solution: a loan bike.

In The Netherlands, most bicycles are used by commuters, so expediting wouldn't work.  However, there are also many places that rent bicycles.  A good bike shop can simply have a couple of dozen bicycles on hand that they then loan out to a (regular) customer, so that they can still go to work, school, social outings, etc..

This is already common practice in The Netherlands.  I believe there exist car garages that do the same, so I don't see why it would be any different for bicycles.

If the bike shop is unwilling to loan you a bike, and you have the money, you can just rent a bike to cover the period you won't have access to your own.  If it happens frequently, you can buy a secondary bicycle for the same purpose.


Need help understanding my grip shifters on my handle bar

You have two shifters. A friction shifter for the front derailer and a 6-speed indexed shifter for the rear derailer.
The shifters are operating by turning the grip front and back (like a motorbike throttle).
The front shifter is on the left. You must learn how to find the right position yourself, because it is a friction shifter, you can move it continuously. After the gear is shifted you must yourself find the position that does not make any bad noise.
The rear shifter is on the right side. There are 6 predefined positions for those 6 speeds, that means 6 different sprockets, chainwheels, at the rear derailleur.
You turn the right/rear shifter towards you to shift to an easier gear/larger cog in the rear.
You turn the right/rear shifter away from you to shift to a harder gear/smaller cog in the rear.
You turn the left/front shifter towards you to shift to a harder gear/larger cog at the front.
You turn the left/front shifter away from you to shift to an easier gear/smaller cog at the front.
If you want to look on the numbers, then the smaller the number indicated, the easier gear is selected.
The gear is not changed immediately, you must turn the cranks that hold the pedals first after operating the shifter. Do not push too hard or the chain can fall or get jammed.
To go uphill, you normally go slower, so you select a smaller chainwheel at the front and a larger chainwheel at the rear. That way you can go push with a reasonable force even if you go slower.
When you want to go fast on a flat or downhill, you select a larger wheel in the front and a smaller wheel at the rear. That way you do not have to turn your pedals too fast.
Do not select the smallest cogs on both sides at the same sides or the largest cogs on both sides at the same time. That is called cross-chaining  and is bad for the drivetrain and will likely be noisy.
As others noted, you should try to change the front gear less often and the rear gear more often. But everyone develops some personal style of shifting after some time. It is important to adjust your shifting to avoid those bad habits that lead to fallen or jammed chains. Especially, do not shift under load. The cheaper the drivetrain is, the worse it copes with bad shifting. Expensive derailers can shift multiple gears at a time, but try to avoid it with yours.


What exactly do seats with a cut out in the middle achieve?

The depressed channel running down the middle of the saddle is what is taking pressure off the perineum, not the actual hole in the middle. Some saddles merely have the channel with no actual hole.


How to remove alu seat post from carbon frame?

What you need is some way to grip or gain purchase on the post so you can apply a force to, then apply the usual methods to free the post from the frame.

Possible means of gripping the post I can think of:

Old quill stem inserted into stem and tightened
Star fangled nut inserted into seatpost, with a long bolt threaded into it.

GCN has a video showing how to use hot water to free up the post. It seems that a substantial amount of force is still needed to pull the post out though.


How to avoid turning the spokes while tuning the wheel

When I build/maintain wheels, I specifically make an extra quarter-turn to the nipple and then quarter-turn backward to release the rotational tension. This was recommended by Sheldon Brown

Lubing the spoke can help, but if your spokes are rusted, you might as well replace them with the new ones.


This is a very old military bike, estimates say circa 1898, credited to a French officer and cycling advocate Captain Gerrard (although actually probably designed by someone else). It is indeed a folding bike, one of the first of its kind. Soldiers on bicycle were a relatively common thing prior to the first world war. Lots more information here, The BSA & Military Bicycle Museum ; and here Captain Gerard history


Where is the grease on my front brake caliper coming from?

Assuming you have hydraulic disc brakes, the most obvious explanation is that you have a brake fluid leak in the front caliper. If the grease isn't appearing anywhere else it must be coming from the caliper itself. Shimano uses mineral oil as hydraulic fluid which will feel greasy, the black color is road dirt sticking to the oil.

You can probably prove this by thoroughly cleaning the rotor, pads and caliper (inside and out) with degreaser, reassembling and applying the brake hard several times. Remove wheel and pads and look for fluid in the caliper (the pads are already contaminated so this won't do any further harm). DON'T try this with the rotor and pads removed as you will over-extend the pistons and they may come out of the caliper body, resulting in all your fluid spilling on the floor. Alternatively you can use a bleed block in the caliper to retain the pistons.

If the bike was bought new the store you bought it from should fix or replace the caliper for free.


How to determine which cassettes I can use with my derailleur?

You can't work out from first principles in advance what kind of cassette your derailleur will work with--you need to know the model, and then look that up to find out what Shimano's recommendations are.

Daniel R Hicks describes how you can determine whether a cassette that you've already installed will work.

"Tooth capacity" is also sometimes referred to as "chain wrap" or just "wrap." This is how much slack the derailleur can absorb; this is a function of the length of the derailleur cage (the distance between the jockey pulley and the tension pulley); the longer the cage, the more wrap. This is expressed as a number of teeth, figured as follows:

(Big ring - little ring) + (big sprocket - little sprocket)

So if your bike has a 50/34 in front and a 12/25 in back, your derailleur needs to be able to wrap at least 29 teeth; if you switch to a cassette with a 30t low gear, you'd need 34 teeth of wrap.

I'm not sure about the exact derailleur you've got, but apparently Shimano has made some version of a 10-speed 105 derailleur (possibly newer and different from the 105 you have) where the short-cage model can handle 34t and the long-cage 40t. So you're probably OK.


Are brake lever reach limit screws necessary for any reason?

Their purpose differs between hydraulic and mechanical brakes.

On these cantilever brakes, the purpose is simply to adjust the rest position of the brake. If you have the screw fully wound out, you should not feel any difference if you remove them.

BUT there is be a real difference in properly bled hydraulic disc brakes:
Here, it is used is to adjust the point at which the brake actually starts to grip to adapt the brake to your hand size. On hydraulic brakes, this is the only way to do that (in contrast, you can e.g. adjust the cable length on cantilever brakes). If an adjustment screws exists, it is most often an integral part of the lever that pushes on the cylinder and cannot be removed. (Especially lower-end brakes do not necessarily have them.)

Depending on your hand size, it can be really uncomfortable if they grip too early. For example, I rode some trails with the brake (BR-M486) gripping too early. To keep my fingers on the brake meant a hand position that got really tiring after some bumpy sections. Then I adjusted the screw so that I could keep the lever close to the handlebar in a rest position and my hands never got tired from that again. (Of course, a similar thing probably goes for the brake point being too close to the handlebar.)


Chain length when swapping between cassette sizes (11-28 and 11-23)

It should be fine.

The chain will be a little bit longer than necessary when using the 11-23, which may give some droop if you're running bad gear combinations (e.g. small chainring+small cog), but nothing serious.

Never run with a too short chain. A bit long is OK.


is the dry blue manufacturer-applied threadlocker the "stick" version?

It is hard to say for sure how threadlocker gets pre-applied on bolts at factories (most likely not by hand, but who knows).

However, its polymerization happens after contacting the metal, not because of drying on air.

From the Wikipedia article:

  Most thread-locking formulas are methacrylate-based and rely on the electrochemical activity of a metal substrate to cause polymerization of the fluid.

A somewhat counterintuitive property of threadlocker is that it "dries" in airless conditions.

  Typically, thread-locking fluids are methacrylate-based, and cure anaerobically.

If the fluid is left in an open container without any contact with metals, it will remain liquid.


Bike tires need air every ride...is this normal?

If you're putting in 5 or maybe even 10 PSI every week, that's not too much out of line; it's normal for tires to lose a little bit of pressure over time.

If your tires are sinking down to much more than that, you may have slow leaks. If both tires are decreasing by the same amount, perhaps you have older tubes that need replacing. If one tire is doing this but not the other, you may have a very slow leak. Try replacing the tube and see if that fixes the problem.


The DT Swiss C 1850 Spline wheels on that model of the grail have an inner width of 22mm, which will take a 33mm tire.

There are many rim/tire width charts on the web if you search for them, but here's the official one for DT Swiss wheels.


How can I repair a swollen tire allowing visibility on the inner tube (picture provided)?

The picture does not make the situation totally clear, but it appears that tube is not centered in the tire, and the tire is not centered over the rim.  This tends to happen especially near the stem, because the thicker part of the tube gets caught between tire and rim and prevents the tire from sliding into place.

Deflate the tire, then press the valve stem in about 1/2 or 3/4 inch while you wiggle the tire to get it around and under tube.  Inflate slowly, and if you see the same thing again, repeat the process.  It may take two or three tries to get things lined up..

(If, on the other hand, what we're seeing is the sidewall failing and the tube pressing through the sidewall then the tire's toast.)


How do I remove this back wheel axle nut? 90s Peugeot mountain bike

That lock groove is for a washer between the cone and the locknut, and there's no way to have a nut on the axle that locks into it. So you can ignore it.

What you need is a proper 16mm ring spanner. Even an adjustable wrench could well strip that nut. If you have to go to a bike shop or some other workshop to use one, do that. Or just buy one, since you're likely to need it.

Commonly those nuts are done up ridiculously tight for a reason. Often it's because that derailleur protector is only held on by the one nut, so if bumped it will tend to rotate and loosen the wheel nut (the one you're trying to undo). Rather than getting a proper derailleur protector (and that keys onto the frame), a "solution" is just to do that nut up really tight. Which also puts pressure on the cones, so people will often back the cones off a little to stop the wheel binding. It's a classic case of "now you have two problems" (or here).


how do you develop the strength to be able to hold a aero right angled forearm position?

It's all about core strength, not arm strength.  If you want to ride like this for long periods of time you should be supporting most of your weight with your core muscles - not your arms.  Your weight should be on your sit-bones, anchored on your saddle.  Then your back and abdominal muscles stabilize your pelvis and share the load with your arms.  Your shoulders should be fairly relaxed and your grip loose.

I've have good results from following Tom Danielson's 'Core Advantage' book.  It's specifically about core exercises for cyclists and has a stepped approach to take you from untrained to pretty fit.


Is It ok to store your bike outside for 8 hours/day?

If weather is the concern, yes.  You will get some damage over time.  Most of that will just be accelerated wear of all the normally wearable components.  Keep your chain lubed or it will rust.  You will go through grips, tires and seats faster.  Any bolts that aren't alloy or stainless will rust.  Non-stainless cables will rust through.

That is not the only concern though.  You will be exposing your bike to a greater opportunity for theft or vandalism, especially when it becomes obvious that bike sits there all day.


Can I use a Vittoria Zaffiro 700 * 25c road bike tyre with a hole in outer rim of the tyre?

Install the tire and pump up to pressure and see if there is any bulging which would indicate the chords are damaged. Damaged tires belong in the trash.

If there is no sign of chord damage and you decide to use the tire, I would strongly suggest 2 or 3 layers of duct tape or similar as a patch on the inside.  Not only will this provide additional strength but it will reduce the chance of gravel or debris getting into the hole.

FWIW, for small holes such as this I will use Shoe Goo to fill the hole and prevent debris from getting to the tube.  First I inflate the tire to a pressure above where I ride and then work some Shoe Goo into the hole. After the Goo cures overnight and the tire pressure is reduced to normal, the tire will squeeze the hardened Goo and hold it better.  If unfamiliar with Shoe Goo, it was originally marketed for repairing worn tennis shoes. It goes on like silicon caulk, remains flexible but is much harder than caulk.

Last tip: The repaired tire is always installed on the back wheel and I position the repair at the valve stem so I can easily check for any signs of bulging every time I inflate the tire.

Shoe Goo


Do you oscillate your diet along with your riding?

Either is fine - in fact on this timescale there's not much difference.
My suggestion:
I suspect that what's most satisfying for your body and your desire to measure will be somewhere between the two - probably something like 2300 Cal on your off days and 2900 on your riding days.  This should be quite achievable - a handful of cheese added to your pasta example and another energy bar on your riding days and you're well on the way.
Reasoning:
The human body is very good at averaging out calories burnt and calories taken in.  This is easily demonstrated: the recovery eating phase lasts several hours (though tapering fast especially regarding glycogen), and carb loading (not needed for up to 90 minute efforts) happens the day before the ride.  You'd see a weight fluctuation if you weighed yourself daily, but that happens anyway and hydration would affect that too.
If you're trying to maintain your weight and muscle mass, with that sort of level of riding, you should be fine with a sensible  balanced diet eaten to hunger - tracking your calorie intake isn't necessary, but if you want to do it, that's fine, except that your estimate of your requirements may not be perfect.
Your body can store enough glycogen for that much effort, so losing muscle mass to fuel your rides really isn't an issue, especially as you're snacking.  If you're worried, some small protein intake during/after the ride would do no harm (even just the little bit you get from energy bars with nuts in, for example).  I sometimes do a 75 minute early morning fasted ride (32km, just under 800  Cal which seems like a good estimate - yours seems high but not implausibly so).  In that case I start a protein drink towards the end, which seems to help my recovery in terms of muscle fatigue/aches.
I take your uneven pattern much further - every couple of weeks I do an all-day or even all-weekend ride, and then you really can't take in what you burn (Strava says 8000 Cal for Saturday's 400km).  The excess hunger lasts 1-3 days, but my weight recovers in a similar timescale (when I first started distance riding there was a permanent drop after each long ride, but as I didn't get weaker in the gym I don't think it came from muscles).  Yes there's some energy-dense junk food in there, but that's optional; I happen to like chocolate.
As for your worry about the stress of fluctuating intake - yes, it's fine.  Most of our human ancestors had no choice (could they afford much more than rice/potatoes/bread every day, with meat once a week - or what could they gather in season, how often did they hunt successfully) and anyway couldn't measure their calorie intake.  Your bowel movements might settle into a new pattern, but I wouldn't expect so much as a mild stomach ache


Which is safer: country road vs highway?

This is highly dependent on where you live and the driving+riding culture in the area.

For example: In the town I live in (Midwestern US), heading south or south east on country roads is fine -- people are calm and aware for occasional cyclists. Heading northwest its a tossup between the country roads and following the highway. And heading southwest, I'd follow the highway as long as I could.

I've driven along I-40 in Arizona before, and it looked like a wonderful place to bike (esp. near Flagstaff); You could see cyclists on it. On the other hand, other highways may not be good, like I-5 in California from LA to SF (where I doubt it is even legal to bike; if I had to travel along it, I'd rather use PCH 1, depending on the destination).

You have asked two (presumably) trustworthy people, who should have a good idea of the area and suggest using the highway. I'd heed their advice. This is probably the best way to check itineraries (ask someone who knows). Systems like google maps and stuff sometimes give you shorter itineraries or whatever, but they aren't necessarily safer roads to ride on or not properly verified data.

Highways have some advantages -- regular traffic flow and usually enough room to ride on the side of the road versus narrower roads in the country. Plus, if you do get hurt on a highway, someones likely to see you. On a country road, it isn't clear. The threat of a drunk/sleepy driver on a wide highway shoulder is pretty unlikely relative to something like being hit by a car on a country road cause someone was driving recklessly and/or didn't see you. A shoulder is effectively your own bike lane (modulo the occasional broken down car), and it's ideal to use if you have one. Only downside is you have to be a little more careful with debris like glass bottles and what not in some areas.

Plus, on some country roads, you have to deal with wild animals. Less so on highways during the day.


Without more info about the specifics of your crank set it's hard to answer exactly what size you need, but yes, they can be replaced. You will want to know the bolt pattern and bolt circle diameter. What brand is the crank set? Shimano? Maybe add a picture. Depending on the condition of the chain and cassette, it may be wise to consider replacing those too.


Eddy Merckx serial number identification

Looking at the frame, I initially doubted whether this is a genuine bike - there were plenty of people making stickers and slapping them on average bikes. The paint job isn't particularly fancy, and the lugs on the frame are not scalloped like a high end bike. The fork is Columbus, but there is no Columbus sticker on the frame.
But, "Eddie Mercx" is etched into the bottom bracket, and this was too much effort for a knock off, especially in something that wasn't on show. So I think it is a genuine item.
As @carel suggests, the official web site should be source of truth, or there may be a historical group that helps to track the history of old bikes (often run by fans, as the factory is more interested in selling new bikes - they don't make money from fans who dwell in the past)


Can you change the rear hub on a tubular cyclo cross wheelset with out riping the tubular tyre off?

It is almost impossible to rebuild a wheel (i.e., new hub and new spokes) without removing the tire. Leaving the tire on, would mean leaving the spoke nipples in place.  (It is a good idea to replace the spoke nipples when rebuilding a wheel.  You will also require new spokes).  It is a big hassle threading the spoke into nipples that are stuck in one position.  Almost all wheel builders will first remove the tire.  It should be possible to carefully remove and reuse your tubular tire anyway, so this may be less of an issue than you think. (What adhesive did you use?)

11-speed compatibility options

In terms of replacing your hub to get 11 speed compatibility.  There are a few different options to consider.  Custom wheel builds are not cheap.  If your rims are not in pristine condition or insanely expensive it may be more cost effective to sell your wheels (or wheelset) and buy purchase a replacement wheelset that is 11 speed compatible. (Note an 11-speed rear wheel can take 10-speed cassettes with the appropriate spacer). You may also check what rear hub you have, some more recent hubs that started their life as 8/9/10 speed hubs were designed to allow the cassette freehub bodies to be changed in order to enable 11-speed compatibility (although this is not a common feature, it does exist and you may be lucky enough to own one).


In road racing, what are "rolling attacks"?

"Rolling attacks" are a series of sequential attacks on the peloton by typically a team or a group of riders acting as a team.  R. Chung covered this nicely in the comment section, but I will expand a bit here.

Typically you get two or three groups of riders  together to orchestrate this (where a group may consist of one or more riders).  The first group launches an attack (preferably when there is a lull in the peloton after a recent hard effort - gotta make it hurt to respond). They will either escape or the peloton hunts them down.  The exact moment the first group is caught, the second group launches another attack.  The moment they are caught the third or first group (depending on how many groups of riders you have) launches an attack. You then keep repeating as necessary or logical.

The idea behind doing this is that typically only a few riders (often tasked with this job) hunt down the breaks.  If you have the manpower, by doing this you are working to wear out the other teams by brute force. Eventually, if you are lucky, the peloton may decide not to respond and you have yourself a break or you have tired out key players on the other teams.  Again this only really works if you have a manpower advantage, leaving a few riders who are never involved with the attacks to conserve for the sprint or some other similar strategy.

As a caveat, I will add that I am not certain how much this strategy shows up in big shows (such as the Tour de France or Tour de Giro) as they know so much about the capabilities of the various riders, but I saw this was fair bit in our local racing scene.


I need to change my fork after having an accident with my bike

These folks should be able to help out for super cheap:

London Bike Kitchen


I recently built a wheelset for Tannus tire liners and studded tires. Then I noticed that both tires lose pressure quite quickly but one of these lost it in a very alarming manner (15% of gauge pressure loss per day).
For the tire that lost pressure not as quickly as the other, I estimate it was caused by the Tannus tire liner compressing due to the high pressure placed on it. Wait three weeks and the pressure loss has reduced to that of an ordinary tire. So it appears the Tannus liner is compressed about as much as it will compress.
For the tire that lost pressure quickly, the cause was mainly a loose Presta valve core. I didn't make it loose, it was that way straight out of the factory. I tightened it with an adjustable wrench and the quick pressure loss reduced to that of an ordinary tire.
So, moral of the story: if you buy an inner tube with a removable valve core, you can't expect the valve core to be fully tightened straight out of the factory.


Attaching crank arm with Shimano SLX M660

The cap is like the star-fangled nut on a threadless headset - it's only there to hold the crank in place when you do up the pinch bolts.
If the pinch bolts aren't holding the crank in place on their own, something else is wrong, and you really need to fix that. If the crank splines are worn because the shop fitted it wrong in the first place, they should replace the crank.


PF30 cup came out of frame, can it be pressed back in or should it be replaced?

Once you get the bearing and cup off the spindle, you can assess the state of the bearings a little. Turn them with your fingers while pushing hard in both the radial and lateral directions. This kind of test isn't perfect because the loads applied in use are so much higher, but sometimes it can reveal notchiness or roughness that lets you know you'd be better off replacing them.

Unfortunately, between the creak and the ejection of the cup, it's likely that the bore on the frame is either oversize, roundness-challenged, or both. You could check it with calipers if you want. Any such issues can have an adverse effect on bearing life, as the creak indicates the cup is moving a little which in turn means the bearing alignment won't be ideal. If there's no or minimal wear or roughness detectable, on a personal bike I think it's fine to just re-use it and see what life one can get out of it. While it's convenient I would lift the bearing seal and degrease and re-lubricate it, but that's optional. One nice thing about doing that is once you get it clean and re-check how it feels, you can get a better read on whether any roughness or notchiness was caused by contamination versus damage to the races.

On the other hand, it wouldn't take much perceptible wear for me to just replace it while it's out.

Retaining compound is a good idea and hopefully it will eliminate the creak.


I've used platforms similar to this one:

  http://www.universalcycles.com/shopping/product_details.php?id=22313&category=1669

But after looking around a bit, I saw this product, which looks a little more rugged since you screw your actual cleats into the platform to clip it in rather than relaying on the molded plastic of the platform:

  http://problemsolversbike.com/products/deckster_clipless_pedal_adapter

But have found that these platforms are really a temporary solution meant to let you ride to the corner store, not meant for long term use. Since the platforms clip in like a shoe, they can clip out like a shoe and they float around a bit, so don't feel super stable. Also, they make the pedal top heavy, so the platform always ends up on the bottom and you have to flip it around (gently) so you can get your foot on it - if you hit it too hard when you're trying to flip it, it's easy to knock the platform off.

Your best bet is to try to get the stuck pedal off and put on the pedals you want to use. Here are some tips on removing a stuck pedal: Removing a stuck pedal

I've never had to resort to using heat, but I've been told that it's a sure fire way to loosen a stuck pedal because aluminum expands more than steel when heated.

But first, as mentioned above, make sure you're unscrewing in the correct direction, and use a good quality pedal wrench.


Maybe.
Given your link, it came with 23mm tyres.  You may still have that size, read the side wall to confirm.  If your current tyres are a different size, then this example will be off.
A 23mm tyre is about 23mm wide, and a 28 is.... 28.  There is some variance on size because of rim width.  So ideally you would use a vernier caliper to measure the maximal width of your tyre, when on the rim and inflated to the highest pressure you would typically use.  Lets assume they measure out at the nominal size.
Your planned 28mm tyre is 5mm larger than a 23mm, so it will use 2.5mm more in width on each side and about 5mm more in height.  The height is on one side because the rim doesn't move, whereas the width change is on both sides of the center line.
With your wheels and 23mm tyres in the bike, find something that is 2.5mm thick.  A hex driver/allen key is a good candidate, or a sliver of wood like a chopstick, or some plastic of that thickness is good too.
Feed this feeler-gauge around your bike frame.  Specific pinch points to check are

Chainstays, both sides
Seat stays, both sides
Fork tines/legs, both sides
Mudguard/fender stays, both sides

Now double over your feeler gauge so its 5mm thick, and check

Rear brake caliper, underside
Brake bridge over the rear wheel, underside
Front brake caliper, underside
Fork crown, underside

If your feeler fits everywhere, then a 28mm tyre will "fit"
HOWEVER a close tolerance is not necessarily good - you do need additional space for dirt/mud, and simple flex while riding.  I would recommend an additional 2mm as a bare minimum.
I have a 90s Cannondale which really should have a max of 25mm tyres.  I have a 28mm in the rear, but refitting it after a puncture means a 3-handed dance between the QR, the rear brake lever, and pushing on the rim at the chainstay to get it all centered.   Otherwise the bike will subtly rub and erode my wheel and left chainstay over time.
Also, if you have rim brakes then a wider tyre can be difficult to fit when inflated.  That same bike has problems getting the tyre through a 105 rear brake caliper even with the brake's QR opened.  It's easier to inflate the tyre with the wheel re-installed.


Totally okay - you're focusing on the word tandem, when really both you and tandem riders want a "high spoke count" wheel.

36 spokes or 40 spokes or even 48 spoke hubs and rims exist but not so common in 44 spoke.

The values that are important in sizing a wheel to suit your bike are

Over-Locknut Distance or OLD.  This is the space between the inside of your rear dropouts, and should be equal to the width of the hub from outside the bearing locknuts on each side.
Cassette/freehub/freewheel mount - the system for mounting your gears should be the same, else you will need a new cassette to suit.   Yours is a Shimano cassette
Number of gears - this relates to the width of the cassette - yours is 9 speed.
Through axle or Quick Release - what does your frame take?  Appears to be Quick Release in photo.
Rim diameter - yours is 700c which means 622mm.
BRAKES - your bike has rim brakes, so you MUST have a rim that has a brake track and is rated for rim brakes.  Some rims are disk brake only these days.

You should be able to reuse your tyre and tube, unless you elect to get a wider rim and run a wider tyre like a 32 or 35mm.  This will totally depend on frame clearance at the seat and chainstays.

Also wheels intended for Tandems may have fittings for a drum or band brake  on the rear hub.  This may be useful or not in your situation.

ANSWER:  Yes you can use a higher-spoke count wheel in your normal bike, exactly the same as you might use in a tandem or a touring bike, provided all the other details match.


What type of ebike motor would work best for a 13” tire?

Good afternoon,
Whilst I appreciate you prefer to use bicycle parts, you may find it beneficial to search for scooter or wheelbarrow hub motor/wheel. The benefits of which would be - they're water tight, they're simple (a nut to hold the axle at either side is all you need to secure it) and they have lots of tread.
You can also run it using a motor controller which has a "walk assist mode" - this will disable the throttle and lock/limit the speed to around 6km/h, alternatively as previously discussed - physically impede a thumb throttle to limit input.
A 36v "hoverboard" battery would be fine (and small), all the torque is at the bottom end of these motors so that's not something you should worry about.
If you're looking to run more than one motor simultaneously - that's not something I have ever successfully accomplished, it is possible you can just disassemble a hoverboard - use  the footplate pressure sensors to turn the motor controller on when you grab the handles, the gyroscopes as the throttle - so the cart accelerates when you lift the handle(s), each of the wheels to drive one side of the cart.
** In fact, don't do any of that, I think just invented something!
All of these things exist, regrettably I am unsure of the rules in relation to posting links but if you're still looking, let me know.


What do I need to replace my singlespeed freewheel cog?

Park tool has a guide to figuring out what type of free hub/freewheel you have, and what tool you need to get it off.

https://www.parktool.com/blog/repair-help/determining-cassette-freewheel-type.

With that knowledge you should be able to to figure out what type of replacement freewheel/spocket you need (or two, as you have a flip-flop hub).

Update:

Also see the Sheldon Brown page on Freewheels.

Depending on what the freewheel thread turns out to be, you should be able to get a replacement freewheel that has a more standard lockring.

You might consider creating a 'bodged' tool to get the current freewheel off. You might be able to 'drift' the lockring loose by tapping the ring around with an old screwdriver and hammer.


No, that won't work because first and foremost tube rubber isn't going to liquefy and re-solidify and be fine; it's going to burn and be weak.

Traditional vulcanizing patches do more or less what you're talking about. The vulcanizing fluid acts on the rubber to permanently fuse the patch and make the tube as good as new. It's easy and gives predictable results.


'Best' Gear inch to start with on a fixed gear? Moderatley hilly area

I'd start with a 70 gear inch ratio for a while and adjust from there. Then change your rear cog by one tooth at a time till you figure out what works for you. I would stay within 65 to 75 gear inches for most on-road riding. You could get away with 75+ gear inches if you lived In a flat area or were just a beast of a masher.

The problem with fixed gears in hilly areas is that you'll have to spin very quickly when going downhill.  Keep that chain tight and your momentum will help on the climbs.

I prefer to ride slightly higher (about 74 gear inches) since I live in a hilly area and want to be safer when spinning on decents.  It may take a few weeks to get used to riding fixed, but your legs will adjust quickly, so don't be too hasty to switch things up.

Also, consider the skid patches with your setup. You don't want to have a setup with only 2 skid patches and wear down your tires too quickly.  http://www.Bikecalc.com has a good gear inch and skid patch calculator to help figure it out.


What are the things called that you attach a rack to?

I'd call them "rack mounts", which is what pake, surly, and all-city tend to use on their websites to describe them.  Alternatively you could call them "braze ons for racks" or even "rack bosses".

From Sheldon Brown
http://sheldonbrown.com/gloss_bo-z.html

Boss
A bump or protrusion. This term has several specific bicycle usages:
Cantilever bosses are the brazed-on pivots attached to frames and forks for cantilever brakes.
Shift lever bosses are brazed-on pivots for down-tube-mounted shift levers. Most newer "road" bicycles have the shifters mounted on the handlebars, so they use the old-style lever bosses as attachment points for housing stops
Older style freewheel pullers had two (or four) protruding bosses that engaged the notches of the freewheel body. This system was prone to failure when removing freewheels that were unusually tight. The development of splined freewheel removal systems made this obsolete

Braze-on
A small fitting permanently attached to a frame. On traditional steel frames these attachments are held on by brazing, but the term "braze-on" is also used for fittings that are welded, glued, riveted or molded onto frames of other materials. Typical braze-ons include cable stops and guides, water bottle cage mounts, shift lever bosses, cantilever brake bosses and cable stops, pump pegs, etc.


At what point does one need to replace a chain ring on a mountain bike?

While replacing any part comes down to when you want/can do it, you should replace any damaged part immediately. That's true whether you experience symptoms of failure or not.

Missing teeth on a chainring may not seem like a big deal until another one breaks off, causes chain slip or a dropped chain that sends you over the bars and into a tree or rock. Suddenly a missing tooth seems like a big deal.

As a side note, you should probably invest in a bashguard/ring if your knocking teeth off your chainrings!


Fortunately 700c is a standard size that describes most road bikes.

As regards rim size, check out Sheldon


You could also buy a pizza delivery bag and bungee strap it to a front or rear rack. Or modify the bag yourself to attach to a pannier by stitching some hooks or loops of Velcro to the sides.

Most pizza bags are 18" x 18" and about 5" deep so plently of room for records and maybe a snack for later ;)

You can buy them online for rather cheap.


Adding gears to a childs trike pickle pashley

Normally I would say "you wouldn't start from there", but since you have...

Since you've managed to add a cassette, I assume you're reasonably confident with tools. You're going to have to make a derailleur hanger that sits in the right place. If you can get a sealed bearing over the axle it'll be easier, but if not you will need to make a plain bearing that can be split to get it onto the axle. Then use that to locate a short arm that attaches to the frame and holds the hanger in the right place. I suggest starting with a scrap bike (from the tip if possible, you only need the derailleur hanger and a short length of frame, the rest can be damaged beyond recognition). One problem is that the derailleur will hang very low, with those small wheels it might not survive long in the hands of a child.

If that sounds impossibly daunting... sorry. That's why I started with "I wouldn't start from there". If you have to pay someone else to do much of the work it'll end up cheaper to buy a trike that has been built with gears from the start.

Quick Sketch

Looking from the back of the trike,you need to build the blue bit. The green bit is the bearing on the rear axle, and the really bad photo of a rear derailleur shows where that will go. The blue blob at the top is where you bolt the new part onto the frame of the existing trike.

Where I'd start from if I could?

While I'm usually reluctant to say "this brand, and only this brand" here, there really aren't any other options for readymade kids recumbents that I know of. So... The KMX kids recumbent trike (or in the UK). If you can find one and put your kid on it, see what happens. If you can get him off it without tears and screaming... maybe look at an upright trike again. If you do need to go with an upright, I'd approach Pasley and see if they can put gears on that trike, or suggest a framebuilder who can. But if you can braze or weld, building something like that will be a good start on a second career as "building stuff for my son" because from experience, you will get a better product even if you're a bit ham-fisted, and you'll definitely save money. But that assumes you have the "spare" time to do this stuff :)

But seriously, try a recumbent trike, anything that he can even vaguely fit onto will do as a first attempt. They're more stable and more robust, so as a result more fun. You might find it helps to use toe clips with heel support, or the Shimano SPD "clipless" shoes and pedals - I can't imagine riding a recumbent without them.

Also, able bodied kids ride the KMX trikes... or want to :)

To make shifting easier you could try longer levers. These are some vintage ones:

But you can more reasonably get shorter ones from a scrounged bike and make an extension for one of them. Take the other one off, they just unbolt. That way if you stuff up the first attempt you can try again with the other one :)


Is it worth it to reverse the wrap direction of handlebar tape at the brake levers?

Yes, it is worth it, because it adds to the longevity of the useful period of utility for your tape, and is more likely to be comfortable and stable in the bargain.

Ideally, you wrap to the outside of the drops, figure 8 around the hoods, which will leave you wrapping from back to front on the tops.

In other words, starting your wrap from the bar end at the bottom of the drop, you wrap the tape so that it crosses from the frame side to the outside of the bar. This direction will necessarily be opposite on the other side of the bar.

So counter-clockwise from the rear of the drop on the non drive side of the bike, and clockwise on the drive side. On the tops of the bars, the tape should pass under the bar toward the bike, and over the bar away from the bike.

That fits the rotation direction of your grip, and will hold the tape in place, rather than forcing it looser (or off).


Is an IP68 rating sufficient to protect a phone during a 12 hour ride in heavy rain?

It should be.  That's how I navigate on all my rides, wet or otherwise (phone on the bars).  I've done this for a few years, but not completely without incident.
Some tips:

Make sure all port covers are tightly closed; I even grease mine very lightly.
Consider how you will charge if necessary (I might otherwise plug in to a battery pack or my dynamo while going along)
It's possible for phones to leak after taking damage, even seemingly cosmetic damage.  My last phone did this after coming off the bars one too many times*.  I dried it out successfully a couple of times but then needed to replace the screen.  It's now my backup phone and not waterproof.
If it fails, how bad is it? Will you be lost in the cold and wet, down a large sum of money for a phone, or will you be able to ride home on known roads and repair it?  Should you have a backup map/route sheet?
Touch screens don't respond well when wet - will you need to touch the screen while riding?  I made a little windshield that keeps the rain off while I'm moving, but on steep hills or in stop-start traffic it gets annoying.
If you're considering putting it in a waterproof pouch for further protection, I've found they aren't all very waterproof, and anyway the clear plastic fogs to the point you can't read the screen if you let in even the slightest moisture (the window is colder than the phone).

BTW Garmin only claim IPx7 for their dedicated devices, so it's up to how well you trust the manufacturer and whether the seals have suffered over time.

* It's too heavy for most phone mounts and tends to find the weak spots and snap them, too fat for others so doesn't clamp securely.  The screen turned out to have slightly come away from the shell after the last impact with the ground at 35km/h.  It already looked battered.  The replacement has a lanyard clipped to the bars


Is it common to own two MTBs for different weather conditions?

This can not be answered objectively for all people. Your current conditions, budget, space availability and preferences all play a role in such decision.

The advantage of having just a spare wheel set is space saving. If they are for disk brakes then they are the fastest to swap.

The advantage of having more bikes is (more bikes! Duh!) you can have them tuned for different purposes or types of riding. Even the same model of bike you can tune more for aggressive climbing and other for comfort (long rides) or for aggressive downhill practice. Switching from one bike to another is less hassle than having to re-tune the bike every time you decide to go for a different type of riding.

Another advantage of multiple bikes is that one of them breaks in such a way it is difficult to repair, you can just ride the other one while the broken one is under service or waiting for spares to arrive.

Some people do have a bike for training and other for racing. I do not carry that practice, so I do not know the specifics, but I'd think that they have the top-level bike in a safe place while the other one takes the risk, wear and tear of routine training. The bikes would have very similar configurations but maybe the training one is heavier, lower spec'd components and maybe use on that one the tires that aren't new but still have some use life on them.


With the usual disclaimers that I'm not a doctor, etc, it sounds like you strained an intercostal muscle when you hit the pothole.  Intercostal muscles are the muscles between your ribs; they assist in breathing, which explains why you experience pain with deep breaths.  As with any muscle strain, the only cure is time and resting the muscle.  Wrapping your chest with an elastic bandage might help.  Consulting the sports doctor would be better than asking me, but my bet is he'll tell you the same thing.

But to answer your actual bike question, I don't think it has anything to do with bike fit.  It's a physical injury.


How come some cyclists lean forward at a 45 - 60 degree angle and I don't?

To complement Neil Fein's answer, the rider's position is almost entirely controlled (given a particular rider) by the geometry of the bike.

Compare the following bikes. In the first image of a hybrid bike, the saddle is slightly below the handlebars. In the second image depicting a road racing bike, the saddle is well above it, forcing the rider to lean farther over to reach the lower handlebar position. In the third image of a time trial bike, the seat height and handlebar height have remained relatively unchanged, but the seatpost is at a much steeper angle and the intended grip brings the arms much further forward, forcing an even more horizontal position in order to put the hands on the bars.

Now look at the riders in this next series of images to better see the difference.

(source: bicycledutch.wordpress.com)

(source: www.flickr.com)

(source: bikesportmichigan.com)


road bike to road bike with mountain bike fram with full suspension

Adding rear suspension to an existing bike not designed for rear suspension is hard - you'd have to cut the tubes, weld them and make sure the result is safe.

Adding front suspension to a bike is not so hard, but it will change the geometry. You need to find the specs of the fork and headset that are in the bike already, and then find something compatible (threadless/threaded, steerer tube diameter). However, adding a front suspension to a bike which wasn't really designed for it is not necessarily advisable -- the rest of it may not hold up to the abuse you may be thinking of giving the bike after you put on a fork.

As pointed out in DWGKNZ's answer, you can't swap a lot of the parts (the Specialized Demo 8 uses pressfit BB, so you'll get a new crank at the minimum), but given the tools required and the fact that the sirrus comp is a nice bike, you're better off selling it and buying new parts. On top of that, the parts for mountain biking (e.g. derailleurs, etc.) are built more robustly for mountain biking than for the road so you'd likely want to buy better parts anyway (esp. for a nice frame like a Demo 8).


The first thing to check is that your rear wheel can take a 10 speed cassette. If this is the case, then you can move to step two, which is picking compatible rear derailleurs and shifters.

A 10 speed Shimano road shifter needs a 7-9 speed mountain/road rear derailleur or a 10 speed road derailleur. A 10 speed Shimano mountain shifter needs a 10 speed mountain shifter. You're proposing a road shifter with a mountain derailleur (both 10 speed) which won't work.

Once you know the cassette size you want to deal with, you can choose the appropriate model of rear derailleur (long cage, medium cage, short cage, for example) by looking at the required capacity.


What to do with the new parts on an old bike I want to dump?

Dumping is possible, but dump it somewhere useful rather than into a landfill.

I suggest a bicycle cooperative, who will use your parts to refurb other bikes, or if the parts are completely unserviceable then they will separate and recycle the different metals

A quick google returns these coops in New York, in no order:

http://times-up.org/bike-co-op
https://cargobikecollective.wordpress.com
http://bikecoop.nyc
https://www.bike.nyc/recycleabicycle/

These are not retail shops, instead they are workspaces or groups where riders work on their own or donation bikes.  The coops may be attached to a shop but are separate entities.

Different coops have different "eligibility" parameters for assistance, so it may be worth reading their websites before selecting one.

I know of one coop that limited their "zone" to 5 square kilometres (a city of ~100 square km)  and excluded assisting anyone who owned a car.

Another thought is that a donation to a registered charity may have tax benefits for you.


Can you help identify this classy, German-built city bike?

This is the 2015 version of the Winora Aruba, 8-speed bike.
Solid build, but sadly, it's a bit too expensive for my needs as a city bike: costs around €700 new.


Is this a conspiracy of bike and wheel manufacturers, to maintain a steady demand for tubes and tires?

No, because if it worked as well as you suspect, someone would have made it happen and taken all the money tube and tire companies are getting.
The reason pneumatic tires continue to be used is because air itself is a great spring.  Additionally, being a fluid, it has the benefit that all of the air in a tire can work as a spring all the time. The rubber in the tire casing also works great as a shock absorber, and just like the air, the entire tire flexes at once, not just the contact patch, no matter which way the tire is oriented. These two effects mutualistically complement each other, and make the tire what it is.
If you had a solid strip of rubber, only the rubber in the immediate area can do the job, so you'll either have a harsher ride, or a heavier tire. The same problem exists with other air-free alternatives as well.
Now sure, you could make a full-suspension bike with a suspension tuned to make a smooth ride despite solid rubber wheels. But you'll quickly find out that such a suspension, both the changes to the frame, and the components, will be considerably heavier than a regular tire. And bikes are an application that is highly weight sensitive.
Other applications, such as Tanks, have a different set of constraints and trade-offs, and so there tracks are preferred, and they have some pretty sophisticated suspension systems allowing them to drive over bumps and stuff at high speeds, because when hauling around 50 tons of armor, another extra ton for a good suspension is worth it.
Sometimes, things stay the same way forever and ever because they just work.


Which rims should I purchase to avoid breakage of spokes?

You should pay attention to both.  Ideally, if I wanted to make the strongest wheel possible, I'd build a 36 spoke wheel with a double wall rim with eyelets, and double butted spokes, and lace it 3-cross.  All of these components help absorb or redirect impact.

Double wall rims are definitely the biggest part of this.  The torsional stiffness of a double wall can definitely keep things rolling straight. I've even had a wheel with two broken spokes that had a very tall double wall rim, that I rode like that for 2 years before replacing those spokes, because the rim wasn't that far out of true.  Of course, this was on a fixed gear with no brakes, so brake rub wasn't a problem...

Eyelets reinforce the spoke/rim interface, making it stronger and helping to avoid nipple pull-through.

Spoke count makes a pretty big difference simply because the more spokes, the more impact gets divided between separate spokes.  The cross pattern matters because every point two spokes cross, some small part of the energy divides off to the crossed spoke.  More than 3-cross can be a problem though, since you start having spokes crossing at the j-bend where they go into the hub, which can cause more problems.

This last one is going to seem a bit counter-intuitive.  Double butted spokes are thinner in the middle than they are at the ends.  One thing this does is make the spokes a little bit compliant.  Whatever forces are acting on them, they can stretch or contract just a little to adjust for.  Also, the weak point of straight-gauge spokes is at the J-bend where they enter the hub.  Any mechanic will tell you, that's where they break.  The double butted spoke adds a perceived weak point, the middle of the spoke, where it's thinner.  Since that part is the smallest bit compliant, it can absorb more impact without breaking.


The Bicycle Wheel by Jobst Brandt touches on this:

Some rear hubs that have done a version of this include the Ritchey Zero or Z-hubs. The road Zero hub had a 21.3mm center-to-right flange measurement and 28.6 center-to-left, so combined with a 3.65mm or so offset rim it was dishless. (It didn't need an asymmetrical frame, but moving in the left dropout is secondary to whether this sort of idea can work.) These wheels do function and didn't seem to have any grievous reliability problems, so maybe they should have been copied more, but they also don't push the concept all the way to total symmetry.

I believe the deal with this is that there are some physical reasons why if you take the center-to-right flange measurement off a road hub and say, "Okay, if that's strong enough for lateral loads in one direction, then let's make the left one the same," you wind up with a wheel that buckles easily from lateral loads in either direction. In other words it's not just a matter of what bracing angle is good enough per side; in the highly tension-disparate wheels we have, the better bracing angle side is somehow making the whole thing more stable.

I haven't done the deflection tests that would be needed to test whether this is true, but what I have done is build a number of SP generator hubs with their dainty 23.5mm per side center-to-flange dimensions. Those wheels have the unlovely trait that when you do routine side-loading on them to reduce spoke windup, you can feel that they're extremely laterally flexible, and it's easy to induce a "column buckling" type failure if you're not careful, something I have no trouble with in other wheels. People ride them and they work, but from what I've experienced it's clear to me that once you're down to bracing angle numbers like that on each side, the wheel threatens to become too unstable.

Another piece of the puzzle is that, as with so many aspects of bike component design, competitive and sport use is the economic backbone of the industry and so what works there drives what gets made. How it applies here is that existent rear road wheels have been strong enough for competitive use under athletic riders, so doing anything about their lack of strength from being so heavily dished has never been seen as a priority by the mainstream, or worth compromising anything else to fix. Virtually no advantage is ascribed to increasing the strength of the wheel against vertical loads, so why sacrifice any lateral strength to get it, even if it were just in one direction? Were this not the case, offset rims would be ubiquitous, because they work against the problem in a manner that gives up nothing other than some additional costs (and have become common on prefab sets).


The specs of the thru-axle that you need are here. The one that you need is T1707, which is 12×142 with a thread of M12×1.

The T1707 and the T1711 both fit a 142×12 mm with a thread of M12×1. The T1707 has an axle length of 162.5 mm, while the T1711 has an axle length of 175 mm. I couldn't find the TCR specs for this online, but since I ride a Giant Propel Disc, which has the same thru-axles as a TCR, I was able to take mine out of my bike to measure it. I found that it measured 162.5 mm (see photo). This means that the T1707 is the correct axle.