Bicycle Mechanics - Loctite on Hollowtech II pinch bolts

I've got a Shimano 105 triple crank and BB (FC-5603). It's a couple months and just under 1000 miles old.
The first 50 miles led to some annoying "clicks" and "creaks", but I then read up on how to properly tighten both the pinch bolts and the crank cap appropriately.

Then about 300 later I got some subtle clunking when I really got on the pedals had. I repeated the grease and tighten procedure and it was cool... for another 250 miles.

I'm 200lbs, and ride up a lot of hills - probably 5000ft a week conservatively. It's not the end of the world to do this every few weeks, but I'm thinking some loctite on the opposing pinch bolt threads might do the trick. Those are consistently getting loose it seems.

I own a torque wrench, but it's a huge 1/2" drive, wobbly needle type you install truck hitches with. Pretty clumsy and prone to strip a little M6 bolt I fear.

Anyone think loctite instead of Phil grease on these pinch bolts is a poor idea?

Perhaps your crank arm is stripped? I guess loctite would be a temporary solution if it were. I did a cross country trip and some riders "new" bikes from the shop weren't torqued to spec at all and caused some damage to the arm. Perhaps it wasn't ever properly torqued.

Torque spec on the pinch bolts I think is 12-15 Nm. Which is a lot of torque. Most likely it was not torque to that level

Do not loctite that ****. Follow the torque spec. Shimano wrote those in for a reason.

Do not loctite that ****. Follow the torque spec. Shimano wrote those in for a reason.

That concurs with my googling - but glad I asked.
Thanks all.

I own a torque wrench, but it's a huge 1/2" drive, wobbly needle type you install truck hitches with. Pretty clumsy and prone to strip a little M6 bolt I fear.


Torque is torque, the 1/2" drive wrench should be fine if you reduce down to the correct size socket.

Torque is torque, the 1/2" drive wrench should be fine if you reduce down to the correct size socket.

Sort of.

15 n-m is about 11 ft-lbs.

For a 1/2" torque wrench, that would probably be pretty far toward the low end of its range, meaning ... the least accurate part of its usable range...

I agree with neil - that big sucka is likely way to big for applying 11psi - if you can even read 11psi on it. This is what you want - and SEARS has them cheaper than Park. Shop around.

http://www.parktool.com/products/detail.asp?cat=13&item=TW-1

I agree with neil - that big sucka is likely way to big for applying 11psi - if you can even read 11psi on it. This is what you want - and SEARS has them cheaper than Park. Shop around.

http://www.parktool.com/products/detail.asp?cat=13&item=TW-1


11 lb-ft =/= 11 psi

Either/or - I just installed a Ultegra Hollowtech II on my hybrid. So I'm quite familiar with the set-up, but haven't read the installation of the 105. For some reason, the number 48 sticks in my mind for those 2 little bolts. And I did use a small torque-wrench. And the stupid end-cap that requires the purchase of a special tool - of course! For that I recall a pre-load tension of 8 - to 11.

I'm terrible with remembering numbers though. I have them backed-up on my hard-drive though.

important tip, tighten the two bolts up in small amounts, one bolt, then the other, back and forth till you reach the recommended torque

important tip, tighten the two bolts up in small amounts, one bolt, then the other, back and forth till you reach the recommended torque

+2 :thumb: