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10

I don't like to be the bearer of bad news, but I've been down this road once or twice. As a hobby, I sometimes pull bike frames out of dumpsters and rebuild them to sell for my cost on Craigslist. I have learned over the years that bicycles, when new, really cost at least $300-400. "Bicycle-Shaped Objects" (BSO's) are sold at stores like Wal-Dart and ...


8

Drivetrain components tend to wear in this order: Chain Rear cassette/sprockets Front chainrings (and the teeth on your derailleur's jockey wheels may last, but the bearings may not) The chain is usually the culprit for wearing out the other two. As it wears, the distance between links effectively increases, and the mismatch between the links and teeth ...


7

Its not about higher and lower end bikes, its about the nature of the bikes and the purposes they are used for and probably some history and snobbery too (-: You can pay a truly staggering amount of money for a mountain bike (or a tourer or a recumbent) with a triple chainset and equally you can get something that bears a passing resemblance to a road ...


7

The cable that moves a mechanical derailleur is counteracted by a spring. To the best of my knowledge the "leave it on the smallest sprocket" theory suggests that the spring is sitting with the least amount of tension on it. The same is true for the cables. Because they have the least tension they are more likely to maintain adjustment over periods of ...


6

The key property is hardness. For uniform materials (like cogs), hardness directly affects wear resistance. The harder the metal the longer it will last. Some digging around wikipedia suggests that typical Brinell hardness values are: pure aluminium 15HB, 6061-T6 aluminium (heat treated) 95 HB mild steel 120HB, 4130 CroMo steel 183-217 HB (90-96 ...


5

Before answering your question I will add the caveat that without seeing your problem and without knowing the exact spec of the bike, this 'quote' could be wrong. For one, you might not have replaceable chainrings. But, assuming you do have replaceable chainrings the cost would be somewhere around 30-35$ (10$ labor, 20-25$ for chainring) depending on the ...


5

I've heard different rules of thumb (rule of thumbs?) about how much use you can get, and remember none of them. What I do know is that not lubeing a chain often enough--actually, cleaning and lubeing--will cause it to wear such that it 'stretches'. Not stretch like taffy, but gain overall length due to the pins and bushings in the links wearing down, ...


4

The answer to your main question is cadence, i.e. the rate at which you rotate the pedals. Most cyclists naturally tend towards a narrow range of cadences where we feel most comfortable. We also have different comfort levels / capabilities for power output. To spin comfortably up a hill (at your preferred cadence and effort level) you'll need to find a ...


3

If your chain was measured and is worn, then by all means replace it. You are going to cause more wear to your bike using a worn chain than having slightly worn sprockets. A worn chain causes uneven wear on the teeth of your chainrings and cassette cogs, eventually this can cause issues with shifting and 'chain suck'. The new chain you selected looks ...


3

Primarily, the range of your drivetrain affects your fastest and slowest speeds (for a given cadence). Often there is no perfect range and selection of gearing will normally involve some compromise (Either losing top end speed or making climbs difficult). The importance of the gear range of your drivetrain therefore varies with your usage scenario, and ...


3

How about a Schlumf drive? The Schlumpf drive is an ultra thin planetary gearing system located at the right end of the bottom bracket, between bottom bracket and right crankarm. Installation of a Schlumpf drive hardly changes [either the] position of the chain nor position of the crankarms. They're probably expensive, but I don't think they have a ...


3

Admittedlty I've never done it before but changing a front chain ring should be pretty easy to do. You can pick up a new or second hand one on your favourite internet listing/auction site, then it should just be a case of disengaging the chain and undoing the bolts that attach the rings. Or am I missing something?


2

I guess that the spring isn't hold the sprocket well. The best is to bring the bike to shop to repair it. But if you want to repair it all alone, first get your rear wheel off, get the sprocket off and check the 3 teeth inside the sprocket - they have to be perfect half-circles. If they aren't, you should replace it. The spring must touch itself on its' ...


2

Just about any new bike you ever purchase will need a good tune up after the first 100 miles, not unlike a lot of cars or motorcycles. It's perfectly normal for most of the parts, especially parts under tension like brakes and cables, to settle and loosen a bit the first few times you ride the bike. It's likely that the cable for the rear shifter has ...


2

You should only need to replace the sprocket, nothing else. If you put on a smaller sprocket to get higher gearing/slower pedalling you need a smaller sprocket, not a larger one. You may need to remove a chain link. Those parts should be standard, the same as on an adult bike, and any bike shop should be able to make the switch. Coaster brakes are common in ...


2

I have bent the teeth on a front chainring before by accidentally dropping the bike on the ground and it hit a rock just on the end of a tooth. I was able to bend it back slowly using a pair of pliers, but I would recommend getting the whole ring replaced. I am unsure as to the price these days, but the thing you need to know when ordering is the BCD - ...


1

Apart from the Sturmey hub, the only other option I know of for a multi-speed fixed gear is something like http://surlybikes.com/parts/dingle_cog You have two sprockets on the rear, and two chainrings on the front, carefully chosen so they work with the same chain length. To change gear, you stop, get off, move the chain onto the other set of sprockets, ...


1

I had the same dilemma and the best idea I came up with is a fixed internal gear hub. Sturmey Archer make a 3-speed fixed hub that looked the goods. The way this works is that there's still no freewheel (the same as a fixie) but there's a gear cable coming out of the hub that allows you to select between 3 gears. On the bike it looks a little like this: ...


1

I use Marine Axle Bearing Grease or Park Poly Lube 1000. However, check out this Question about grease. What makes grease appropriate for bikes? You do need a cassette lockring tool (Park tool FR-5 will probably work for most) to remove the lock ring at the end of the freehub and slide the rear cassette off if you have a freehub style rear wheel. If ...


1

First, to remove a cassette freehub does require a specific tool. The Park Tool version is called the FR-5. There is no need for more than one kind of grease. Use any light bearing grease like the Park Poly Lube 1000. There is a good set of instructions here on how to do the rebuild. From Park Tool's repair help site: Hub Overhaul and Adjustment ...


1

There are a lot of small boutique-factories machining extra-weight-weenie parts that serve three purposes: Provide some weight advantage to very high-end racers who reached the limit of their training levels. That could mean positions in a very high-level race; Satisfy some folks (whose population is increasing) who don't mind throwing money out the window ...


1

Yeah, sounds like it might have bent when you were starting while half shifted, basically shifted under extreme load. I've no idea how much it would cost to fix, but to avoid something like that in the future, you should get used to shifting while stopped. Basically, you shift (only one gear at a time!) then stand up, lift your read wheel, and pedal ...



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