Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   Bicycle Mechanics (https://www.bikeforums.net/bicycle-mechanics/)
-   -   Easy question: chainring compatibility (https://www.bikeforums.net/bicycle-mechanics/554540-easy-question-chainring-compatibility.html)

a_elephant 06-22-09 06:42 PM

Easy question: chainring compatibility
 
Is BCD the *only* determinant of chainring/crank compatibility?

I'd like to buy a new chainring for my bike. The current one is 130 BCD, 3/32. Will *any* 130 BCD, 3/32 chainring fit?

This is for a fixed gear, so I know chainline can be an issue. AFAIK chainrings don't alter chainline, excepting for inside or outside attachment to the crank arm. Let me know if there's something else I need to think about here.

Thanks!

Jeff Wills 06-22-09 07:28 PM


Originally Posted by a_elephant (Post 9148273)
This is for a fixed gear, so I know chainline can be an issue.

For SS/FG use, you should be OK. With some crankarms & chainrings there can be issues with spacing and orientation between rings, but most of those can be compensated for with spacer washers.

Mondoman 06-22-09 07:45 PM

Perhaps the number of mounting holes?

operator 06-22-09 07:56 PM


Originally Posted by Mondoman (Post 9148645)
Perhaps the number of mounting holes?

I've yet to see a non 5-bolt 130bcd chainring.

operator 06-22-09 07:57 PM


Originally Posted by a_elephant (Post 9148273)
Is BCD the *only* determinant of chainring/crank compatibility?

I'd like to buy a new chainring for my bike. The current one is 130 BCD, 3/32. Will *any* 130 BCD, 3/32 chainring fit?

This is for a fixed gear, so I know chainline can be an issue. AFAIK chainrings don't alter chainline, excepting for inside or outside attachment to the crank arm. Let me know if there's something else I need to think about here.

Thanks!

For a singlespeed crankset, in your situation any 130bcd 3/32 will work. Including all 8/9/10 speed "shimano compatible" rings and any "single speed" chainrings. Rocket rings etc. et al. Some of the cheaper chainrings *may* not fit properly even though they are the same bcd as your crank.

Doesn't happen very often but something to watch out for.

operator 06-22-09 07:59 PM


Originally Posted by Jeff Wills (Post 9148518)
For SS/FG use, you should be OK. With some crankarms & chainrings there can be issues with spacing and orientation between rings, but most of those can be compensated for with spacer washers.

I can't think of a single situation where you would need chainring bolt spacers to fit a proper bcd chainring on a crank. The more you space out a chainring (this is only necessary to "fix" chainline the improper way), the greater chance you have of suiciding the ring under load. I've seen it happen.


All times are GMT -6. The time now is 12:11 AM.


Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.