View Single Post
Old 10-05-15, 02:57 PM
  #2  
habilis
Senior Member
 
Join Date: Apr 2015
Location: Morris County, NJ
Posts: 1,102

Bikes: 90's Bianchi Premio, Raleigh-framed fixed gear, Trek 3500, Centurion hybrid, Dunelt 3-spd, Trek 800

Mentioned: 40 Post(s)
Tagged: 0 Thread(s)
Quoted: 2167 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by Seizedpost
Hello all,
I have a 1982 Fuji I just picked up, and I'm trying to figure out how to cure some chain ring wobble.
Originally, when I spun the crank, it wobbled about 1/8". The point at which it was furthest in was the spot by where crank arm. I flipped the crank on the bottom bracket 180 degrees, and then the wobble was greatly reduced. Now the farthest in point (again, eyeing the edge of the chain rings) was 180 degrees from the crank arm. But, it's really not that bad with the crank flipped 180 degrees. It appears to have about 1/16" wobble at the edge of the large chain ring.
My bottom bracket shaft is hollow, and it seems like it's a little tweaked. But, I guess since flipping the crank decreased the wobble, the crank probably isn't perfect either.
So, what do you think? Should I replace the bottom bracket, or just use it in the position where it wobbles least? I'm leaning towards the second option, but would like some opinions.
Since I can't see it, I can only guess. It could be that your crank, not the spindle, is deformed. The crank is alloy while the spindle is pretty durable steel.

When you remove the cranks and rotate the spindle from the non-drive side with your fingertips, do you see any wobble or deformity in the opposite end of the spindle?
habilis is offline