Bicycle Mechanics - relining a UN72 adjustable cup

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cyclezen
10-04-05, 11:45 AM
in an effort to help another get their bike in ridin shape again, I need to 're-line' the inside of a UN72 adjustable cup. The 'lining' that holds that spindle/bearing assembly snug is shot and the assembly rattles around inside the cup.
Anyone have thoughts on what might be useable in there?
would Shimano actually have replacement sleeves?
Otherwise the BB is fine, and we ARE being cheapskates... and want to play with the idea of 'repair'
Do we need to get a replacement cup?
flog away...
I wouldn't waste my time. If a un72 is too many clams consider a un52/53.
cyclezen
10-04-05, 01:59 PM
I wouldn't waste my time. If a un72 is too many clams consider a un52/53.
boy, you are a spoil sport! :)
actually would be great to make the old junk work. I'm really tired of throwing perfectly good stuff away.
I'm really into re-cycling cycling.
For some minor plastic liner, a perfectly good BB should be tossed.
I can only imagine that whomever installed the BB, didn't properly tighten the cup, allowing the movement and the wear of the liner. The owner commented he had always had some 'chain rub' when he really got onto the pedals. I asked why he had never had it looked into? He said he thought it was just cheap junk and 'rub-age' was just par for the course.
DOH!
I have some ideas... I might try refurbing the needed liner by using some p-tex. Properly applied, I'm sure I can get the cup to hold the spindle centered and rocksolid.
let y'all know how it goes...
HillRider
10-04-05, 06:33 PM
Try wraping several turns of electrical tape, enough to get a snug fit, around the non-drive side of the cartridge before you screw in the "adjustable" cup. Or make a shim of thin polyethylene such as from a milk container. You have nothing to lose.
cyclezen
10-05-05, 11:19 AM
Try wraping several turns of electrical tape, enough to get a snug fit, around the non-drive side of the cartridge before you screw in the "adjustable" cup. Or make a shim of thin polyethylene such as from a milk container. You have nothing to lose.
yeah, good idea - MIlk container is also ptex - I use it a lot for other stuff, should work here. Not sure about the tape though. Electrical tape is surprisingly 'spongy'. But I might try one wrap of telfon tape around the milkcontainer wrap to hold it in place while screwin in the cup.
Might be 'goodnuff' and certainly easier than heatgunning in some ptex.
let ya know how it works...
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