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Technical & Reference Section => Tech and Restoration => Topic started by: Jazzchimp on August 18, 2005, 10:37 PM

Title: Fitting BB tips anyone?
Post by: Jazzchimp on August 18, 2005, 10:37 PM
Apart from smacking with a 20lb lump hammer, anyone got any nifty tricks to make the job easier?
Title: Re: Fitting BB tips anyone?
Post by: ORB on August 18, 2005, 10:49 PM
A bb press (i personally think these take the fun out of building)

Lay the frame on the grass with the BB on a bit of wood, place the top cup in the frame and put another bit of wood on the top to hold it in place and then smack it EVENLY.

I have only struggled once.

But, its more fun when the hole is tight.
Title: Re: Fitting BB tips anyone?
Post by: Jazzchimp on August 18, 2005, 10:57 PM
not sure about the words cup, wood, grass, smack, hole and tight cunjure up the right images for me!
Title: Re: Fitting BB tips anyone?
Post by: The-flying-banana on August 18, 2005, 11:19 PM
Jazzy sand the paint from the bb brt on the frame and then grease em before installation also i like boiling water poured on the frame just before i put em in ;)
Title: Re: Fitting BB tips anyone?
Post by: mivvi on August 19, 2005, 01:47 PM
Have a quick question on a similar subject. Which way around are the bearings supposed to sit? Open side of the race facing out or in? I know it sounds a dumb question but they seem to fit either way. This question applies to H/Set bearings too. Thanks lads!
Title: Re: Fitting BB tips anyone?
Post by: birdieman on August 19, 2005, 08:06 PM
JAZZ, The wood and the hammer on the grass is the way i did it ,followed by squeezing them in the vice!!
Title: Re: Fitting BB tips anyone?
Post by: motomagII on August 19, 2005, 08:20 PM
orbs spot on as usual 2 lumps of wood and hammer .works every time no probs

Title: Re: Fitting BB tips anyone?
Post by: TwoBobRob on August 19, 2005, 09:09 PM
Make sure the frame is free of all paint and other crap on the contact areas, cups can be pressed in using a large vice and suitable protective packers, or as Orb rightly says, beat the sh!t out of them using wood and large hammer.

Usefull tip:  put cups in freezer night before fitting, they will contract just enough to make the job a load easier  ;)
Title: Re: Fitting BB tips anyone?
Post by: daz bmx it! on August 19, 2005, 09:41 PM
Yep,hammer and wood every time! As a time served mechanic first thing i was taught,if it wont fit? don't force it,get a bigger Hammer! ;D
Title: Re: Fitting BB tips anyone?
Post by: Chris on August 19, 2005, 10:30 PM
But, its more fun when the hole is tight.

Can't disagree.
Title: Re: Fitting BB tips anyone?
Post by: Dollarbill on August 20, 2005, 10:10 AM
Have a quick question on a similar subject. Which way around are the bearings supposed to sit? Open side of the race facing out or in? I know it sounds a dumb question but they seem to fit either way. This question applies to H/Set bearings too. Thanks lads!

Normally the closed side of the bearing faces against the cup. Bearings should only be installed after repeatedly pounding the cups with a large hammer, just to make sure they're installed proper.
Title: Re: Fitting BB tips anyone?
Post by: CD17 on August 20, 2005, 10:32 PM
BITD I split a headtube on a GT Pro using large hammer & wood to fit a headset.
As for BB bearings-cups if they have alloy cups, I file them down so they fit in, with just a bit of interferance, they wont come loose as the cranks hold them all together & they are so much easier to remove.
Title: Re: Fitting BB tips anyone?
Post by: spinmaster on August 21, 2005, 08:27 PM


But, its more fun when the hole is tight.

isn't it always ;) ;D
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