Bicycle Mechanics - is my crank is more or less junk?

I haven't ridden my bike for about 2 years now because of this

I think the picture will tell almost everything
http://selj.madebymonkeys.net/images/cranklol.jpg

and the crankshaft bit it attaches to is already a bit more of an octagon than a square

it just started creaking one day and on the same ride it started wobbling around for about half a cm. My knowitall uncle tried various spring washers and stuff but it didn't help.

the side with the gears is ok though

this thing is shot right? what all exactly do I need to replace?

You need a new crank arm that is the same length as the one with the gears. There should be a number printed on it (usually 170, 172.5, or 175) that will tell you what length in mm the arm is. What kind of bike is it?

You may also need to replace the bottom bracket, or at least the spindle because the edges are rounded over.

heres the bottom bracket
http://selj.madebymonkeys.net/images/crank2.jpg

that still ok? (even if its been sitting in my garage for 2 years)


The only marking on the arm is "CPI 8" and my empirical measurements put it at 170mm

oh and here (http://selj.madebymonkeys.net/images/bicyccycyclezini.jpg) is the bike

That's a sweet looking little bike. Take the bike and crank arm to your local bike shop...they may have a used crank arm laying around. A friend of mine had the same problem 2 months ago...cost less than 20 bucks to get it fixed. A good LBS is your friend. :love:

Mike

That's a sweet looking little bike. Take the bike and crank arm to your local bike shop...they may have a used crank arm laying around. A friend of mine had the same problem 2 months ago...cost less than 20 bucks to get it fixed. A good LBS is your friend.

Yup. That's a common enough problem that the shop where I used to work kept replacement arms in stock. You have to get the length right and there's two ways the hole can be oriented so you have to get that right. If you aren't too picky about it being an exact match for the right side it should only be about a $20.00 job.

Yup. That's a common enough problem that the shop where I used to work kept replacement arms in stock. You have to get the length right and there's two ways the hole can be oriented so you have to get that right. If you aren't too picky about it being an exact match for the right side it should only be about a $20.00 job.

+1

Diamond or square.

Easy fix.

Git r dun

You may also need to replace the bottom bracket, or at least the spindle because the edges are rounded over.

BB spindle is hardened steel, crank arm is aluminum - it's no contest. The spindle will be OK, unless damaged by other circumstances.