Bicycle Mechanics - Chainring shape

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wayne pattee
04-30-08, 06:02 PM
The 52 tooth chain ring is a little bit out of round. There isn't any bind in the chainring bolts but its off a little. Is that ok or should I replace it?

SweetLou
04-30-08, 06:51 PM
Was it made that way? There are some oval chainrings, like the Shimano Biopace.
monk
04-30-08, 07:00 PM
Out of round as in "up and down" or "side to side?" I assume you mean it's a bit oval. I don't see how that could happen unless it is in fact a Biopace like Sweetlou says.

Al1943
04-30-08, 07:40 PM
If it's not Biopace maybe the bottom bracket spindle is bent?
wayne pattee
04-30-08, 08:03 PM
Yes it is a biopace. They are made that way huh?
OK I feel better now
Thanks for the info
SweetLou
04-30-08, 08:36 PM
There are others besides Biopace. Biopace is the most common one seen though.
Read up on them: http://www.sheldonbrown.com/biopace.html
JanMM
04-30-08, 08:49 PM
Used to have a Sugino Cycloid ring.
wayne pattee
05-01-08, 06:10 AM
should have known to search Sheldon's site.
I have much to learn and many dumb questions to be answered.
Thanks again