Shimano Press Fit BB UPDATE

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hondated
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Joined: 27 Mar 2008, 7:59am
Location: Eastbourne

Shimano Press Fit BB UPDATE

Post by hondated »

I have been building a Trek Madone bike up for months now or rather acquiring the parts to when finances allow and a recent purchase was a BB.
Now having brought it I want to fit it but I am wondering whether this is a job I can do.
To me it seems easy as all I think I need is a length of thread with a couple of nuts and spacers to draw the BB through the frame but before I do can I ask if anyone has done it this way or have you tried it and came unstuck.
Just in case you too are thinking of doing this I managed to fit mine by using an appropriate sized socket as advised by Brucey a piece of scrap wood and a large G clamp.
Slid into place wonderfully.
Last edited by hondated on 19 Sep 2016, 4:05pm, edited 1 time in total.
Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Shimano Press Fit BB

Post by Brucey »

the problems with doing it in the way you suggest are that

a) the bearings might start going in on the slosh and
b) you will likely be pushing on the inner part of the bearing.

b) is a bad way to fit a bearing; the races may well be damaged. Where you have a choice, you should use a length of tube (or a suitably sized socket) to push directly on the outer part of the bearing during installation.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
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hondated
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Joined: 27 Mar 2008, 7:59am
Location: Eastbourne

Re: Shimano Press Fit BB

Post by hondated »

Thanks Brucey good point and I do have a few sockets I can use to do the job.
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Gattonero
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Location: London

Re: Shimano Press Fit BB UPDATE

Post by Gattonero »

Or just use the old bearings as a drift!
Run them for a minute on the bench-grinder, so they get a fraction smaller and won;t get stuck altogether 8)
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...
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