Anybody know about bike cranksets?
I want to change the gearing on my bike to raise the gear rations up. I know very little about bike mechanics and was hoping someone can clear some questions up for me. Its a Trek Hybrid, currently stock 48/38/28 crank on it with 13/34 7 speed cassette. I want to put a 52 or bigger crank on it in the low to mid 50s if its possible.
1. Is this something I can do myself having little background knowledge or would i have to pay a shop to do it? Are there compatibility issues i need to worry about, or are they pretty universal (do i just buy any old crank, pop the old one off and the new one on?)
2. Will I need a new front deraillur? do you have to adjustments on the current one? the stock is a Shimano C102 right now
3. anything else I should know about doing this?
Alright... Looks to me like you are looking to put a road crank on the bike.
If you want to do it at home, you'll need a crank puller, and BB tool if you want to go to a two piece crank. The shop will most likely install it with purchase. A new crankset will almost certainly be cheaper than replacing each of the rings on your current crank set. If you replace just one ring (outer), your gear ratio's will be nuts...
You will need to adjust the fr derailler, but not replace it.
Again, because of the required tools, and adjustments, I'd just bring it into a shop.
Alright… Looks to me like you are looking to put a road crank on the bike.
If you want to do it at home, you’ll need a crank puller, and BB tool if you want to go to a two piece crank. The shop will most likely install it with purchase. A new crankset will almost certainly be cheaper than replacing each of the rings on your current crank set. If you replace just one ring (outer), your gear ratio’s will be nuts…
You will need to adjust the fr derailler, but not replace it.
Again, because of the required tools, and adjustments, I’d just bring it into a shop.
References :
Comment by ct — July 24, 2009 @ 10:42 pm
1. You can probably handle it yourself, but you’re going to need some specialized tools, like a crank extractor and possibly a bottom bracket wrench. There are a number of different crank/spindle interfaces, so compatibility is a concern.
2. Your front derailleur will need to be moved up, but probably not replaced.
3. http://www.parktool.com/repair/
References :
Comment by artmichalek — July 24, 2009 @ 10:53 pm
Go to a shop and get them to put on a 52-tooth chainring, but there’s no need to replace the crank itself. You may also need to replace the middle and small chainrings, since derailleurs are designed to handle a limited jump between chainrings (i.e. will shift from 38 to 48 but not from 38 to 52).
What else… if there’s a bike repair co-op in your city (like Bike Kitchen in San Francisco), take a class there and learn how to do it right.
References :
Comment by slosh415 — July 24, 2009 @ 11:13 pm
1. It is not hard to actually do the work. However, there may be a number of compatibility issues. You have a low end Shimano dérailleur set, which may not allow for a road triple crank set (huge reach between the 52 fr and the 34 r - you may need to replace the larger cogs in the rear cassette). But it might work. Cranks are not always interchangeable. With the group you have I would assume that it is cheaper and easier to replace the cranks.
2. You probably won’t. You will have to adjust the current one (it will need to be moved and then re-adjusted).
3. Unless you like to tinker and have faith in your ability, I recommend a good bike shop. Someone who knows what they are doing could have it done in a very short time.
References :
Comment by Moose C — July 24, 2009 @ 11:48 pm