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Boom torque

My P-38 is about a year old. When I received it, there was a sticker listing a torque spec for the 2 bolts that tighten the boom. It has since been lost.
If your P-38 still has the sticker, what spec is listed?

I am currently torquing the 2 bolts to 40 in-lbs based on discussion with Tim but my memory (getting older) thought a higher spec was list. Occasionally the bike has fallen over, when parked, due to higher winds, and the boom has twisted. I then have to fix in the road, it seems to me if the boom was at the proper torque, it shouldn’t twist.

Any help is appreciated.

Hi Ed -

If the crankset boom can twist when the bike falls over, clearly it has not been tightened down enough. I do not use a torque wrench myself, but just tighten the bolts down by feel. When it gets MUCH harder to rotate the bolts, I stop. Not very scientifc, but it has worked for me over the years. It would not hurt to call Brummer on the phone and ask him for specific guidance on using a torque wrench, just to be safe. If you overdo it, you could break off the brazed-on pinch bolt fittings. Fixing that would be a pain in the ass. Good luck, and let us know what Tim Brummer says.

Safe riding,
Joel Dickman

These three prevent most accidents: seeing, being seen, & (usually) common sense.

While considering how to reassemble the bottom bracket/frame I came across products which offer anti-seize-corrosion protection and enhanced friction. Examples are Park SAC-2 and Finish Line Fiber Grip, which seem to be grease with sand, silica, added to increase friction claiming to require up to 30% less torque. Has anyone experience this type of product?


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