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Mountain Man Dan
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Discussion Starter · #1 ·
Just thought I'd post this information I've found out.

The pinch bolts on the Hollowtech cranks ( non drive side ) are Aluminum. The heads strip super easy ( as I've found out ). As always, they are METRIC. The bolt is a m6 x 19.

I doubt you will find such a thing in a small town hardware store as I've tried ( they have the correct sizes, just not allen ). Home Depot, ACE, Abuchon are where they would be.

I believe a m6 x 20 would also fit, as 19mm is a off number.

Dan.
 

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Never trust a fart
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4,543 Posts
Hmmm.

Biggest thing is to make sure that your allen's are not rounded and that the allen is fully seated into the bolt head.

That is the best way to stop from rounding out those bolts.

And those bolts are not aluminum. If they were aluminum, you would never be able to tighten them to 10.7-14.5 Nm. Aluminum bolts that small would snap at anything higher than 3-4 Nm.

Try to tighten an aluminum water bottle cage bolt to the recommended spec. You will never reach 10 Nm. They snap off when tightened by hand.
 

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Mountain Man Dan
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2,181 Posts
Discussion Starter · #3 ·
So what are they, Stainless? They seem like an awfully soft metal?

The allen was brand new. Possibly it wasn't seated fully.
 

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Never trust a fart
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4,543 Posts
So what are they, Stainless? They seem like an awfully soft metal?

The allen was brand new. Possibly it wasn't seated fully.
I believe they are stainless. But the biggest thing is making sure that the allen is fully seated. I've learned this the hard way from working on cars. A worn tool or one that isn't seated properly will damage a bolt head in a heart beat. I've replaced automotive tools with less wear than the ones at the LBS has where I work.
 

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Mountain Man Dan
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2,181 Posts
Discussion Starter · #7 ·
I believe they are stainless. But the biggest thing is making sure that the allen is fully seated. I've learned this the hard way from working on cars. A worn tool or one that isn't seated properly will damage a bolt head in a heart beat. I've replaced automotive tools with less wear than the ones at the LBS has where I work.
It is possible I did not have it seated fully, working with a big torque wrench is a PITA. Lesson learned. :thumbsup:
 

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Mountain Man Dan
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2,181 Posts
Discussion Starter · #9 ·
I have a smaller one, but it's the type with the bar on top with a needle that reads the numbers. I don't like it at all, seems inaccurate and hard to get an exact measurement.
 

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2,790 Posts
It's my understanding that torque wrenches are not very accurate at the low and high ends of their range. If your 1/2" drive torque wrench has a high working range, it is possible that you over-torqued the bolt. That is why you need multiple torque wrenches in a variety of ranges.

It's also possible to do damage by setting the wrench incorrectly. Been there, done that.
 

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Mountain Man Dan
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2,181 Posts
Discussion Starter · #13 ·
It's my understanding that torque wrenches are not very accurate at the low and high ends of their range. If your 1/2" drive torque wrench has a high working range, it is possible that you over-torqued the bolt. That is why you need multiple torque wrenches in a variety of ranges.

It's also possible to do damage by setting the wrench incorrectly. Been there, done that.
I believe it was seated incorrectly. I had already torqued one of the pinch bolts successfully.
 

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Mountain Man Dan
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2,181 Posts
Discussion Starter · #18 · (Edited)
I got new bolts today. They're black. Torqued them to 11 ft/lbs. I'm ready to ride! Was riding the road bike yesterday....kinda boring.
 
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