Bottom Bracket cup install

oldskoolg

Hello,

Im building my first road bike for a charity ride ive organised. Im now at the stage where the build can commence.

So i went to install my BB cups (its a 105 Groupset) and i can hand tighten them till half the thread has gone into the frame. I was wondering is this the norm, because all the videos ive seen on the net the cups are hand tightened all the way in till they need torqing.

I have made mistakes with the cups previously in that i first bought them too big then bought Italian? Yeah i know. Which is why im now nervous about getting the tool around them and going for home!

Any advice would be much appriciated. ASpologies if this question has been asked before.

Regards
Road bike building virgin...
G

thistle_

You should have spacers between the cup and the shell of the bottom bracket. 2 on the right, 1 on the left or something similar.

The spacers should have come in the packet with the cups and the instructions should say which spacers to use.

oldskoolg

Hi Thistle,

Thanks for the reply.

I bought it new from ribble diddnt get any spacers or instructions? But i have read that my Hollowtech dosent need spacers, but i have also read that they do? Can of worms this bike building lark.

Bozman

Spacers? Isn't that only on a triple.

oldskoolg

I'm not sure about that but I can tell you mine is a double. Thanks Bozman!

forward_loop

iirc spacer only on a triple and then its outside of the BB (between the BB and the crank non drive side)

Is the shell 68mm wide ?

I would be tempted to take it into a bike shop to face the BB and screw on the BB for you - its a ten minute job, and explain what you've done and they will exlpain what has gone wrong - for next time.

It could be that there is just some metal shaving in the thread ? - everything clean ? - no sign of cross threading ?

blackhands

Left hand thread on chainwheel side.

oldskoolg

Hello loop, yes is 68mm have had that confirmed from basso. Frame is me as is the bb cups so can't understand why they won't go straight in. Think I will take it to the bike shop see what they say.. Cheers.

patrickf

Thought spacers are for MTB use?

Anyway, if the cups are new then they'll have some threadlock type stuff on the threads and it's quite normal for you not to be able to hand tighten them all the way.

You can double-check that they're threaded in right by applying a little bit of pressure and unscrewing them - you should feel the thread click into place.

oldskoolg

Thanks Patrick, that could be it there is a load of green stuff on it which could be thread lock. I can get about 3/4 full turns before they stop. Just got a bit worried about fully threading them, because I diddnt wanna mess the frame up if I'd done something wrong. But what you said makes sense. Frame is spanking new as are the cups. So first time in would prob be difficult..thanks.

patrickf

The green stuff is grease. If you look carefully you should see something on/in the threads that doesn't wipe off. It's white/off white I think. This is only on the last bit of the threads - the last quarter to a half I'd say.

If its a standard 68mm BSA frame with 105 HollowTech cups then I don't see why it wouldn't fit. As said before just make sure the cups are threaded right.

Monty Dog

Check the Shimano Tech Docs (techdocs.shimano.com) for your BB/cranks and it'll confirm whether you need spacers or not. If the frame is new, then getting your LBS to chase the threads and face the BB shell is worthwhile - probably explains why the threads are a little stiff.

oldskoolg

Cheers Patrick you were bang on, went in easy. Monty Dog thanks for the techdocs link. Very useful!

Thanks again All, nearly up and riding...

dennisn

blackhands wrote:

Left hand thread on chainwheel side.

Most likely yes, but not so on many Italian made bikes.