Crank arm bolts too tight?

Is it very easy to overtighten the crank arm bolts? The only reason I am asking as on my geared bike there is around 4mm of taper showing on the drive side and 2 mm on the other?

I am worried that one side is "too far down the taper".

Have you got strong arms or a long wrench? If so, the answer is yes.

http://en.wikipedia.org/wiki/Torque_wrench

http://www.lfgss.com/thread6029.html
http://www.lfgss.com/thread15114.html

using a handheld multitool style thing, it would be nigh on impossible. but if it has a long handle, then it would be not so impossible.

you probably have an asymmetric bb tho so nothing to worry about.

I did use a large allen key, same as pictured. But I do have strong arms!

Sorry I was hungover at the time....not the best mindset to build a bike.

I'm using an Italian threaded 111mm BB, I believe this is asymetrical BB - maybe someone would be able to confirm please? If thats the case then its correct. Is it supposed to be longer on the drive side and shorter on the non drive side in that case?

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you will have to give more info than just its threading and length.

i.e. model.

It is not easy to overtighten the bolts. In fact if you just did it as tight as possible it would probably be fine.

I use one of those big allen keys at home, and have used a torque wrench while I was a bike mechanic. Tight with the allen key is pretty much exactly the same as the torque wrench, for me anyway.

Its a Campag Veloce:

Yes I did it pretty tight, then decided it was a bad idea so I removed the cranks and reinstalled with a bit less effort.

If it has been overtightened, does that mean new crank? I take it the bottom bracket will be fine.

Its a Campag Veloce:

Yes I did it pretty tight, then decided it was a bad idea so I removed the cranks and reinstalled with a bit less effort.

If it has been overtightened, does that mean new crank? I take it the bottom bracket will be fine.

Cranks are only really likely to be damaged in the case of under-tightening. Remember that the bolts are not there to hold the arms on, they are there to push the crank over the taper. The crank is supposed to stretch/deform over the taper and be held there by the tension/elasticity of the crank.

Your cranks shoud stay put under hard riding even if the bolt is removed. That gives yo an idea of how tight it needs to be.

Thanks, I'm beginning to think its actually OK.

I've attached some photos of the clearance.

What cranks are they? Maybe a JIS/ISO conflict?

"Shimano cranks, on the other hand, have trouble with Campy BB's.......they tend to bottom out."

"This is a good question that comes up every once in a while. JIS tapers are longer and slightly more angled than ISO. So a JIS crank on a ISO BB will tend to use up most, and possibly all, of the ISO taper."

Campag Veloce

All looks OK

They look very close to the BB shell to me.

Pics of my Veloce 9 speed crankset, 68mm shell, Veloce 111mm bb, and info from installation guide:

http://img690.imageshack.us/slideshow/webplayer.php?id=img01676098882.jpg

Argh, confliction.

Sorry the photos aren't showing, what was the results?

Hopefully album link above working now, it's Veloce 2003, English thread. The instructions are from a spare new veloce bottom bracket I just bought and 10 speed crankset.