carbon frame, torque wrenches, etc
 

Hey guys....I am looking for some advice....I have build up several frames and I restore and work on vintage bikes. Up until now I have been doing things "old school" and hand tightening my parts without a torque wrench. I am in the process of swapping out the components on my Specialized Roubaix and was reading the torque specs on the Park Tools site. I am curious specifically about the brake calipers. On the Park site it says 70-85 for the caliper to frame. It doesn't mention if the frame is carbon or not and it doesn't specifically mention caliper to fork (carbon). Would it be the same regardless?

Finally....since I am always messing around with my bikes, I want to get a decent torque wrench for bicycles. I don't care if it is a bike specific wrench(s), but what brand/model would you guys suggest?

Thanks!
Terry

For work on my carbon bike, I use the Park Tool TW1 beam torque wrench. So far so good. I have a longer beam torque wrench for the larger torque values.

There have been several discussions on this forum regarding which type (beam, dial, "click") to use; many if not all choices are matters of personal taste. Inexpensive "click" models which will be quite adequate for bicycle work are available from vendors such as Harbor Freight and Northern Tool for under $20. There are numerous higher-quality and higher-priced choices as well. Search the forums and make a choice but get one and use it. You will probably need two, actually; a lower-torque one in 1/4" drive and a higher-range one in 3/8" or 1/2" drive for bottom brackets and the like. If I had to choose I would get the smaller one first as you are less likely to damage a larger fastener by overtorquing.

I fully agree on the 1/4-sq drive torque wrench to protect fragile small fasteners and carbon components. However, I also highly recommend a 1/2-sq drive one. Here the problem isn't to protect the fasteners from over torquing but to be sure they are tight enough. Without the torque wrench, most new mechanics will badly under torque bottom bracket cups and crank arm bolts.

I think that the op wants to know if he should use the recommended torques for tightening clamps and such onto carbon frames. Are there different recommended torques for carbon frames as opposed to steel or aluminum frames.

I would also like to know the answer to this question.

For specifics on torque for carbon frames/components, I would contact the manufacturer.

Also keep in mind that the size (length/torque range) you use should be appropriate for what you are working on. For example, don't use the torque wrench you use to tighten a bottom bracket, or pedal, to tighten the bolts on a carbon stem. Keep in mind, that when you use a torgue wrench for carbon parts, you want to get it tight enough, but not so tight you damage the item. A smaller, more precise wrench is needed -- as well as the torque specification. For bottom brackets, pedals, cogs, etc., you're more interested in getting it tight enough. I prefer the beam type since you're able to monitor the amount of torque you currently have, as it comes up to the required torque. In additon to the actual torque, you should note if the item should be lubricated or not, before being tightened.

I use a 1/4 inch beam wrench from Park Tool and a 1/2 beam wrench from Sears. As a general rule don't go over 5 nm (44 inch-pounds) on carbon parts. Dont's go by the torque specs shown on stems when tightening carbon parts. And don't ask me why I say that.

Ouch, my sympathy. :( I believe the torque specs engraved on most stems are for alluminum or steel steerers and aluminum handlebars and are excessive for carbon parts. The specs engraved on my stems are 8 nm and that is excessive for carbon anything.

Exactly! I think the 8 nm is probably the limit for the stem pinch bolts, but way too much for a carbon steerer or handlebar.
"Haste makes waste" also applies in my case.
The new replacement fork was $850.

I bought a beam wrench from Sears.

Reason...

Dial wrenches need to be recalibrated every now and again. You have to send them off for that. Beam wrench gets me in the ball park and I recalibrate it at home.

All torque specs should be had from the mfg.