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-   -   Vintage Conversion: Bottom Bracket issue (https://www.bikeforums.net/classic-vintage/574434-vintage-conversion-bottom-bracket-issue.html)

emeyers10 08-15-09 11:51 AM

Vintage Conversion: Bottom Bracket issue
 
I, naturally, would like to get rid of the one piece crank set up on this Schwinn Continental I'm converting, but do I NEED to get one of those american to euro adapters before installing a three-piece system?
Thanksssss!

bbattle 08-15-09 11:54 AM

Yes.

Bianchigirll 08-15-09 12:26 PM

I agree but wow I have only ever seen one or two of those before.

Charles Wahl 08-15-09 01:59 PM

Give a shout to pastorbobinnh -- he knows all about this, as someone who regularly rehabilitates Schwinners.

badmother 08-15-09 05:02 PM

Just make sure it is the right size. Do not throw away the old stuff before you know it fits. I bought a adapter like this and found my BB housing was slightly smaller than the one it was ment for. Wish they came in several sizes.

Oldpeddaller 08-15-09 06:00 PM


Originally Posted by badmother (Post 9493055)
Just make sure it is the right size. Do not throw away the old stuff before you know it fits. I bought a adapter like this and found my BB housing was slightly smaller than the one it was ment for. Wish they came in several sizes.

.......Also try screwing in the new bottom bracket cups or cartridge before fitting the conversion into the frame. I didn't and the DMR conversion was difficult to remove again when the BB cup threads bound up (too tight to tighten fully).

emeyers10 08-15-09 11:31 PM

Thanks for the tidbits, I'll probably message pastorbobinnh later.
Will probably get the Trutativ American Euro BB-Shell conversion kit...when it says that it "converts American/BMX press-fit bottom bracket shell to accept 68mm English threaded bottom bracket," does that refer to any basic ST bb, like say the shimano un54 or what have you?

pastorbobnlnh 08-16-09 02:34 AM

Yes, you need the conversion kit and I've had the best luck with the UN54 cartridge BBs. So far I've converted 4 Schwinn BBs on 3 bikes (one was a tandem). On the first couple of attempts I tried traditional cup and spindle BB, but they do not work.

The big mystery was always which taper length to use. Each crankset seems just enough different that the 1-3mm difference in length can make a big difference. So be prepared to swap BB until you find the best spacing.

On this Super Sport I used a Phil Wood 119mm BB.

http://i125.photobucket.com/albums/p...pyTACrank1.jpg

If I remember correctly, I used a 121mm UN54 on the Continental.

http://i125.photobucket.com/albums/p...rdCrankset.jpg

The Tandem was a real challenge. The rear cranks used two different conversion kits in order to achieve the best chainline on the timing chain and place the triple drive crank in the correct position. I believe it was a 118mm UN54 that finally worked.

http://i125.photobucket.com/albums/p...uretDuoPar.jpg

On the captain's cranks I used a Nashbar 115mm cartridge BB.

http://i125.photobucket.com/albums/p...gChainView.jpg

top506 08-16-09 06:34 AM

The only other option I can think of is the Shimano Adamas three-peice crank designed to fit an American 1 piece BB shell. Not great comps, but it'll work.
Top

emeyers10 08-16-09 08:10 AM

pastorbobinnh, thanks for the info!
have you converted to any singlespeeds? i noticed that all these are derailleur set ups, and i was wondering a suggestion for spindle length in that case? i seem to be finding a general consensus of 110mm, but considering your experience, what's your opinion?

p.s. it's a conti, btw.

pastorbobnlnh 08-16-09 11:42 AM


Originally Posted by emeyers10
i seem to be finding a general consensus of 110mm, but considering your experience, what's your opinion?

p.s. it's a conti, btw.

I've never converted a Schwinn Astubula BB for SS use, but I'd guess that 110 would be too short, but this only a guess.


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