does a larger cassette require a longer chain?
- Thread starter dexterq20
- Start date
Assuming your old chain was the proper length, I would add 1 link and test it under power through the full range of the new cassette. If the shifts are smooth and crisp up and down the entire range you are fine. If the shifting feels tight and 'grabby' or seems to require more effort than you are used to add another link.
However... I think you should start your cassette off right with a brand new chain; both will last longer and you will receive better performance.
However... I think you should start your cassette off right with a brand new chain; both will last longer and you will receive better performance.
Ya, i gotta agree with Serial Midget: you're going to get the best performance and longest life out of your drivetrain if you replace all the parts at once. Well, not ALL the parts, but the chain and cassette.
Using a new cassette with an old chain usually isn't a good idea, it has something to do with the old chain being slightly elongated from use and thenit not fitting the cassette or sumthin.
Using a new cassette with an old chain usually isn't a good idea, it has something to do with the old chain being slightly elongated from use and thenit not fitting the cassette or sumthin.
Yup. Definitely *need* to replace both the chain and cassette at the same time. If you only replace one, they will not work properly together.
No, you're wrong, are you a mechanic? Don't respond if you don't know what you're talking about.
You're supposed to check the chain on a fairly regular basis, I'd say about every 300-500 miles, for chain stretch. If the chain is stretched to a certain point, you should replace it and it will work fine with your existing cassette and you won't have to replace the cassette (prolonging the life of your cassette, it's called preventative maintainance people). If you have a severely stretched chain you'll have to replace both chain and cassette, and probably a chainring or two.
As for your first question, you should be fine going from a 32-34. Just put in a stand in a gear like 2-2, shift to the big ring in front and check the amount of derailleur movement you have left. If it's REALLY tight (cage close to horizontal) don't shift to the 34 in back or you might rip off the der. If the der. isn't too tight it should shift to the 34 okay, but you'll be in a cross gear. Full suspension makes this issue a lot tougher, and I'm kind of assuming you have a HT.
Take it easy. A couple of years ago I would have said the same thing as Swiss. Why? Because every shop I went to told me that I had to replace the two together. They're trying to sell stuff.
Now that I've found a cool shop I know about checking my chain for wear and stretch after every couple of rides. You're right, if you keep an eye on it, you don't have to replace both at the same time. Not everyone is a mechanic and unfortunately they only know what they've been told.
I know, sorry I guess. But if you're not sure why answer?
I get frustated at these boards sometimes when people talk straight out of thier a$$ about things they don't know about [not directed soley at Swiss]
I have been riding bikes since 1972 and quality bikes since the early 1980s - way back in the time if the free-wheel. Serious bikers who took care of their bikes replaced their chains every few thousand miles - when doing so they also inspected the condition of the free-wheel cogs and front rings. With free-wheels we had the luxury of only replacing those cogs that were worn. Now that cassettes are the standard and relatively cheap many choose to replace both at the same time.
I replace chains on my road bike every 1000 miles and cassettes every 2000 miles. On my mountain bikes I replace the chain and cassette every year. I like crisp shifting and I've never had a chain snap on the trail or the road. Having riden with hundreds of people over the years I have witnessed enough chain breakage to know that I prefer to run chains and cassettes in as close to perfect working order as I can get.
Getting a new chain and cassette at the same time is a sound bit of advice.
< I am a mechanic, and I gotta agree with Midget on this one.
first of all, chains are cheap.... if you like to play in the mud (like we do here in WA state) they do wear pretty quickly. I replace mine anually.
Chain wear guides aren't all that accurate. The bearing surface inside the chains need only wear .020 - .030 to be worn, but you wont usually see that on most chain wear gauges because they take a sample of 5-6 links only. (.020 x 6 = .12 of an inch) and that would be a pretty badly worn chain, and a tenth of an inch is easy to miss.
If you replace your cassette, it's a good chance you need a new chain unless it's been replaced recently.
You need a bit longer chain for a larger cassette. All things remaining the same, if your chain was the correct length before, adding the 34t gear increases the diameter of the low gear. That increases the total gear length, so you would have to have more chain to keep the adjustment correct.
If the derailleur is the correct size, there is no reason that you can't have your gears able to go Big-Big and Little-Little both properly. Other than the wear issue (it puts sideways stress on the chain and gear train) it's within the design limits of the drivetrain.
The idea behind a forum like this is bikers helping bikers. Often people will pipe up with advice because it has worked for them. There may be some bad advice (it's free, after all) but that's why it's called a discussion. Not "ask the bicycle god"!
Last but not least, Just because someone disagrees with you doesn't mean they're full of ****! There is plenty of disagreement within the bicycle community as to what works, what should be done and how it works. Bike shops are out to make money, but they can't afford to keep screwing over their customers. If word gets around that a shop keeps padding the bill by replacing parts that aren't necessary to be replaced, they go under (mountain bikers tend to be pretty tight knit... word gets around quickly)
* edit
btw, chain "stretch" isn't actually stretching, its the bearing surfaces wearing and allowing slop... which elongates the chain.
first of all, chains are cheap.... if you like to play in the mud (like we do here in WA state) they do wear pretty quickly. I replace mine anually.
Chain wear guides aren't all that accurate. The bearing surface inside the chains need only wear .020 - .030 to be worn, but you wont usually see that on most chain wear gauges because they take a sample of 5-6 links only. (.020 x 6 = .12 of an inch) and that would be a pretty badly worn chain, and a tenth of an inch is easy to miss.
If you replace your cassette, it's a good chance you need a new chain unless it's been replaced recently.
You need a bit longer chain for a larger cassette. All things remaining the same, if your chain was the correct length before, adding the 34t gear increases the diameter of the low gear. That increases the total gear length, so you would have to have more chain to keep the adjustment correct.
If the derailleur is the correct size, there is no reason that you can't have your gears able to go Big-Big and Little-Little both properly. Other than the wear issue (it puts sideways stress on the chain and gear train) it's within the design limits of the drivetrain.
The idea behind a forum like this is bikers helping bikers. Often people will pipe up with advice because it has worked for them. There may be some bad advice (it's free, after all) but that's why it's called a discussion. Not "ask the bicycle god"!
Last but not least, Just because someone disagrees with you doesn't mean they're full of ****! There is plenty of disagreement within the bicycle community as to what works, what should be done and how it works. Bike shops are out to make money, but they can't afford to keep screwing over their customers. If word gets around that a shop keeps padding the bill by replacing parts that aren't necessary to be replaced, they go under (mountain bikers tend to be pretty tight knit... word gets around quickly)
* edit
btw, chain "stretch" isn't actually stretching, its the bearing surfaces wearing and allowing slop... which elongates the chain.