bike building Q
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- scottON
I ordered a new 170mm bontrager crank for my old fuji S.R.R. Frame... I disassembled and removed the old crank assembly to make way for my shiny new gears... The threaded lock rings inside are pretty mashed up and the bearings are ready to fall out. The new crank is a 3-piece with only the arms, gears, and axle included.
My question is: what parts do I need to purchase to make my new crank sit nicely and spin freely inside the frame?
I am a total novice trying to figure this thing out but a lack of knowledge has gotten me stuck at this point.
- sisu0
Go to a bike shop.
- detritus0
Not really the most appropriate forum for this kind of query, I'd've thought. Anyway, whenever I'm stuck with something like this, I have a dig through YouTube, as there are a few bike shops/heads who've produced basic tutes for idiots like us.
- boobs0
You need what's called a bottom bracket assembly. And you need to be sure to get one with the correct thread.
- nocomply0
try asking on http://www.bikeforums.net/
- freeskihp0
eh, you kind of fucked yourself over. 3 piece cranks are largely intended for BMX frames. As such they come with pretty large diameter, press-in bearings. Road bikes on the other hand use small diameter thread in bearings called a Bottom Bracket that are generally sold separately from the cranks themselves. The bottom bracket is the axle that connects the two arms. Take it to a bike shop but there's a pretty good chance that what you just bought is totally useless