jazzy_cyclist

Sorry if this is a dumb question, but here goes...

So I'm about to install the Shimano compact cranks which use the external-bearing HollowTech II bottom bracket. Park makes a BBT-9 too which fits the splines, but it's just a wrench. How can you accurately torque this without using a torque wrench? Is there a socket version that one can use with a torque wrench?

Thanks.

BlastRadius

How apropos, I was just wondering the same thing.

Pete Hamer

Shimano makes a tool that fits onto a 1/2" drive ratchet. I think Race Face is making one too.

Here's a link to the Shimano tool page. The one you want is TLFC33.

https://bike.shimano.com/catalog/cycl...=1142279544870

Wil Davis

from the Park Tool site:

"Tighten fully, approximately 305 to 435 inch pounds. When using the BBT-9, and grabbing the tool about 6-inches (15 cm) from the cup, apply about 60 pounds (27 kilograms) of effort to tighten the cups."

- Wil

thurstonboise

FSA makes a 1/2" drive socket too.
It works pretty slick as long as you don't use it with a 3/8-1/2 adapter.

fmw

It would be pretty hard to overtorque it with the BBT9. It just isn't long enough to do any damage. Just crank it teeth-clenched hard and you should be fine. The non-drive side is screwed on with a little wheel on the BBT-9. Finger tight is fine for that. Then torque the bolts that hold the non-drive crank to about 125 in lb. or so. That should do it.

jazzy_cyclist

I guess the "teeth-clenching" technique will probably work. I don't have a great sense of foot-pounds (because I don't do it that much), but some of those sockets are designed for impact wrenches which would certainly be overkill.

Thanks for the tips.

BlastRadius

I was thinking more about how to gauge 4-6in lbs for the tension cap. That's more crucial as overtightening it will overload the bearing.

Pete Hamer

That may be who I was thinking of instead of race Face.

Pete Hamer

I always thought that was strange too. Give us a torque spec but no way of measuring the torque.....what? I think that they give a torque spec for the adjuster cap just to give us an idea of how tight it should be even thought they never expect us to use a torque wrench. You just use your best judgement, if the bearings develop drag then they are probably too tight. If the crank slides side to side theyare too loose.

I forgot to mention, the splined bottom bracket sockets for ratchet wrenches are more conveneient. You don't have to remove the tool everytime it comes around to the chainstay, much faster. The socket also clears full suspension swingarms which is very nice.