Bicycle Mechanics - Dura-Ace chainring bolt torque?

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View Full Version : Dura-Ace chainring bolt torque?


AeroDog
05-19-04, 08:41 AM
I cannot find the torque spec for the chain ring bolts on a Dura-Ace 7800 (10 speed). In fact, on the Shimano web site, there's little tech data on the 7800. Thanks in advance for any help.


RegularGuy
05-19-04, 09:29 AM
The Park Tool website suggests 70-95 ni- lbs for steel chainring bolts and 44-88 in-lbs for aluminum chainring bolts.

http://www.parktool.com/repair_help/torque.shtml

You would probably be safe tightening your chainring bolts to 80 in-lbs regardless of what they are made of.

I've never used a torque wrench to install chainring bolts. I use blue loc-tite and crank them down until they feel right.

RegularGuy
05-19-04, 09:38 AM
To confuse matters a little, Barnett's suggests a minimum of 50 in-lbs for steel chainring bolts and a maximum of 35 in-lbs for "lightweight" bolts.

Also, the blue loc-tite recommendation is controversial. Some folks crank them in dry. Some use oil. Some use grease.


RegularGuy
05-19-04, 09:54 AM
Well, I looked at the Shimano website and found nothing....zip, zilch, zero...for DA 7800 chainring bolt torque specs.

AeroDog
05-19-04, 11:22 AM
Well, I looked at the Shimano website and found nothing....zip, zilch, zero...for DA 7800 chainring bolt torque specs.

Thanks, RegularGuy. The bolts and nuts are so light they feel like plastic, hence my fear of overtorquing. In the past (with steel) I always did it by feel with nary a problem.

drroebuck
04-20-05, 11:38 AM
I downloaded a spec sheet for Dura-Ace crankset. The alloy bolts should be tightened at 6-13 in/lbs.