Pinch bolt torque

[Neil E.]

45 zokes on a 2011 with M6 allen screws. All screws heavily greased to prevent corrosion. Top crown with 2 screws I went 7.5 ft lbs, lower crown with 3 screws I went 5 ft lbs on each.

I know some use a different system by tightening only 2 on the lower crown. The values I'm using "feel" right for M6 screws, but I'm wondering if anyone thinks this is too much torque.

[pscook]

Jut remember that grease on threads decreases resistance to turning, so your effective torque is higher. Your torque is effectively doubled from a dry value using a lubricant. That being said, you put the equivalent of ~15 ft/lbs (dry) on the top and 10 on the top.

Sorry that I don't know what the best torque value is, but I do need to know.

[GMP]

I've been running 8Nm lower on two bolts and just snug the third, 12Nm upper, with anti-seized bolts. No slippage and good action. Torque is not doubled, but increased 20-30%, from a machinist book in the shop at work.

[Neil E.]

Thanks,

12 Nm upper = 8.85 ftlbs
8 Nm lower = 5.9 ftlbs (two bolts)

Sounds like I'm in the ballpark, maybe could reduce the lower slightly with all 3 bolts torqued.

[andoman]

Sorry to hijack:
Are those the same numbers for the SACHS forks?
I found here on the forum: 15NM top clamp bolts, 9NM center bottom, and only just snug down the other two on the bottom clamp.

[husley]

Originally Posted by andoman

Sorry to hijack:
Are those the same numbers for the SACHS forks?
I found here on the forum: 15NM top clamp bolts, 9NM center bottom, and only just snug down the other two on the bottom clamp.

Yeah, what he said

[pscook]

Originally Posted by GMP

I've been running 8Nm lower on two bolts and just snug the third, 12Nm upper, with anti-seized bolts. No slippage and good action. Torque is not doubled, but increased 20-30%, from a machinist book in the shop at work.

Gotcha, I was trying to remember my machinists values and seem to remember the 50% was for assembly lube as opposed to never-seize. I'll check my sources again, because I don't want to use or provide faulty information. But the reality still stands that lubrication lowers your torque value, even if I can't get the values correct.

Thanks for the values, I have to run downstairs and "adjust" some bolts. Would those torque values apply to 43mm WP forks?

[GMP]

The clamp is the same design so I would use the same torque. These #s are a matter of opinion, but the consensus is that the manual is wrong, values being way too tight. I've played around with the lower bolts, torque 1, snug 2, torque 2 ,snug 1, makes no obvious difference. I've also been going lower on the torque but have yet to induce slippage. Ultimately what you want is the least clamping force that will retain the fork tube. Mine have been reanodized and as such the outer tube surface is a little more rough than stock, so maybe this helps, but I have never heard of anyone else complain of slippage with low clamp torque values.

[andoman]

Thanks!
Makes sense. I, too, will experiment.
I like the idea of a little less torque on two bolts vice more on one.

[Jakobi]

Terry Hay says 3 bolts is over kill and to just run the middle one. I have done the opposite and just run the top and bottom. Snug and then slightly tighter. Definately not cranking down on them.