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Shoping around for a new bike, I noticed that the Lemond Reno has a Shimano chain and a Sram Cassette. I have heard that when changing your chain you should often replace the cassette at the same time, and that both must be of the same brand. Can they be compatible?
 

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not true....

All chains and cogs on derailleur equipped road bikes have a 1/2 inch pitch. It's best to use the proper chain width (9 or 10 speed) with any cassette. A cassette needs to be replaced if the chains skips on any of the cogs when a new chain is installed. Chains should be changed when the length increases from it's new 12 inch per foot to 12-1/16 inch per foot. A new cassette should also not be used with an old chain with a lots of wear.
 

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C-40 said:
All chains and cogs on derailleur equipped road bikes have a 1/2 inch pitch. It's best to use the proper chain width (9 or 10 speed) with any cassette. A cassette needs to be replaced if the chains skips on any of the cogs when a new chain is installed. Chains should be changed when the length increases from it's new 12 inch per foot to 12-1/16 inch per foot. A new cassette should also not be used with an old chain with a lots of wear.
I went to an LBS that I do not frequent regularly because they were the only one that carried veloplugs in my area. I thought since they had a hard to find item that I wanted I would give them my current business which included a Park Chain Whip and Cassette Lockring Tool.

I asked a few questions and the person waiting on me asked if it was a new install and I replied I was moving the cassette over to new wheels.

For some reason the person waiting on me felt compelled to explain that you should never replace a chain without replacing the cassette. I told him that my LBS replaced my chain when it was worn and I did not realize that shifting had become sluggish until after the new chain was installed. It shifts like a champ now. He said he was sorry, that he did not agree. If I understood him correctly he would not replace the chain until the cassette needed replacing.

What is up with this?
 

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Chains are pretty cheap, cassettes are not. A worn chain will trash a good cassette. A worn cassette will cause skipping and shifting problems with a new chain but won't hurt the new chain in the short time it takes to realize the cassette is trashed. So... I disagree with your LBS guy, it's just the opposite in fact.

Always replace a chain when installing a new cassette. Again, chains are cheap so why not. But if you don't let your chains get too badly worn, the cassettes will outlast chains close to three to one.

I've found that by replacing the chain every 2000 miles. I'll get about 6000 miles out of a cassette. YMMV.

I use SRAM chains on my Shimano drive trains. Just need to use 9spd with 9spd and 10 with 10.
 

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didn't team disco chef machanic suggest that us, no-pros replace our chain annually?? so far last couple year i've replaced only once and so far it's smooth as the day i installed it and i ride 6 days a week/120miles. i run D/A 10.
 

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YMMV you betcha!

ethebull said:
I've found that by replacing the chain every 2000 miles. I'll get about 6000 miles out of a cassette. YMMV.
I've found that by replacing the chain when it reaches 0.5% elongation (per Campy recommendation) I get 8-10K miles out of a chain, and double that from a Veloce (steel) cassette. YMMV :)
 

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Kerry Irons said:
I've found that by replacing the chain when it reaches 0.5% elongation (per Campy recommendation) I get 8-10K miles out of a chain, and double that from a Veloce (steel) cassette. YMMV :)
You think you get more durability out of a Veloce cassette than a "higher" level Campy cassette? I have a Centaur and Chorus and thought a Record might be less durable because of the Ti.

Thanks
 

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the long story...

Posted below, is more detail that slightly contradicts my original posting. Although changing a cassette with every chain is not necessary, waiting until the chain elongates by 1/16 inch per foot is not the sole indicator of a worn chain. It's entirely possible to wear out some of the cogs on a cassette LONG before a chain elongates by 1/16" per foot (.5%). I've used a chain as long as 6000 miles, but not the 8-10,000 that Kerry claims. Even lubing my chain after every ride, the rollers are extremely worn after 6,000 miles on my 10 speed chains. The elongation may only be 1/4 of the allowable maximum at that point. I do spend a lot of time with a high chain tension, climbing with a 28T chainring. That may be part of the reason I my chains don't last as long. At the opposite extreme is the person who changes chains every 2000 miles and only gets 6000 from a cassette. I'd expect at least 15,000 miles from three chains and a cassette. Here's the long story:


None of the common chain wear measuring tools produces an accurate measurement of chain elongation (change in pitch) because they add roller wear to the measurement and most measure over a very short length. The roller wear can be as large as the elongation over this short length, so the tool may report twice the actual elongation. The result may be a chain tossed when it's half worn.

The best way to measure elongation is with a 12" scale. Place an accurate 12” scale on the edge of a pin. The pin at the opposite end will be totally covered when the chain is new. As the chain wears, this pin will begin to “peak out” from under the scale. Change the chain before ½ of this pin is exposed. The maximum allowable wear is 1/16” (.063”) per foot. One half of a pin is slightly more (.070 inch).

Elongation is only half of the chain wear issue. The rollers also wear - often as much as 20 times more than the pins and bushings (which cause elongation). New rollers will measure about .205 inch in between them. When this distance increases to .235-.240, I consider the chain to be shot. It is possible to have this much roller wear and very little elongation.

Changing a chain long before either of these wear criteria is met is not likely to increase cog life. It's entirely possible to wear out at least one or two cogs over the life of a single chain. I've used a single chain for 6000 miles, and worn out one cog, even though the chain showed little elongation. The only practical way to detect a worn cog is by installing a new chain. If the chain skips on a cog, while pedaling under a heavy load, then the cog is too worn to use with a new chain.

The best way to maximize cog life is to alternate the use of two (or more) chains, changing every 1-2000 miles. With this method a new chain will never be installed on worn cogs. When all the chains in the rotation are worn out, then most likely the cassette will be too. There might be a valid argument for including a third chain, but it all depends on the cost of the chain relative to the cost of the cassette. For example, if chains cost $40, the cassette cost $120, and chain life is 4000 miles, the cassette could be used for 8000 miles. The cost per mile is 2.5 cents. If a third chain was included in the rotation, the cassette might be useable for 12,000 miles and the cost drops to 2 cents per mile.

After measuring several chains, I know that mine will never come close the maximum elongation, even if used for 6000 miles. For that reason, I don’t even bother measuring elongation any more. I have a home made plug gage, made from a 6mm hex wrench, ground down to .070 inch thick. If it drops between any two rollers, the chain is shot and I trash it.
 

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So maany different variable in determining chain life

-Cadence
-milage
-Frequency of re-lube
-environment (Humidity, rain, dust etc.)


as C-40 & kerry alluded to.......chain elongation is the best measure of when to replace.

A casette usually lasts about 3 chains for me. I can usually tell visually when it's time.

Your LBS is trying to sell you a new casette more frequently.

Len
 

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Cassette choice

lookrider said:
You think you get more durability out of a Veloce cassette than a "higher" level Campy cassette? I have a Centaur and Chorus and thought a Record might be less durable because of the Ti.
I doubt that Veloce is any more durable than Chorus or Centaur, just cheaper :) A tiny weight penalty for Veloce, but not enough to affect my riding in any way. I'd have to hear something new to convince me that spending more will get much improvement. Record will wear very fast due to the Ti cogs. Same for Dura Ace. I can't imagine why anyone would pay that much for a cassette that wears out quickly and saves maybe 80 grams (two swallows of water).
 

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C-40 said:
The best way to measure elongation is with a 12" scale.
Where can you get a 12" scale? I assume this is not a common ruler?
 

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Rulers

DIRT BOY said:
Where can you get a 12" scale? I assume this is not a common ruler?
All you need is a decent ruler with 1/16" gradations, though 1/32 is better. You can eyeball 1/16" pretty easily when you have the ruler held up against the chain. After all, this is not a precision situation where a tiny fraction of elongation takes you from "just fine" to "busted."

BTW, A fire truck has 8 wheels and 4 fire fighters. 8 and 4 makes 12. There are 12 inches in a foot. A foot is a ruler. Queen Elizabeth is a ruler. The Queen Elizabeth sails the seas. There are fish in the sea. Fish have fins. The Finns fought the Russians. The Russians are Reds. Fire trucks are red. And that's why fire trucks are always rushin'. I thought you'd want to know :)
 
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