Vintage motorcycle main bearings

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Truckedup
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Vintage motorcycle main bearings

Post by Truckedup »

Helping a friend with a vintage 1000cc Ariel Square Four engine....It's like two tandem 360 degree twins geared together.....
The cranks are supported by ball bearings on one end and a bushing on the other end. The bushings look like bronze with a thin babbit coatings...The bushings are worn....replacements are in short supply.......
I suppose one option is to have the babbit repoured....Another option is to make one piece bushings from the proper material..Kibblwhite offers these for similar main bushings on BSA..They call it "mill certified bearing bronze"...
Another friend is a talanted machinist who will can make the bushings.......The crank journals are 1.25 diameter....The engine not highly tuned and might see 5500 rpm...
Any ideas?
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
PackardV8
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Re: Vintage motorcycle main bearings

Post by PackardV8 »

The catalog is filled with electric motor bushings. What is the OD and width? FWIW, the 1.25 ID x 1.5" OD x 1" width is a stock catalog size for a motor bushing.
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hoodeng
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Re: Vintage motorcycle main bearings

Post by hoodeng »

PB1 or LG2 are two that will work well for custom bearing applications, is the crank hardened at the journals? If so, the previous materials will be fine, if not that will be why the the originals had run bearings.

Draganfly could be worth a look.

Cheers.
Geoff2
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Re: Vintage motorcycle main bearings

Post by Geoff2 »

Have you tried the UK, Ariel being a British bike? Ariel club for info?
leahymtsps
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Re: Vintage motorcycle main bearings

Post by leahymtsps »

You can have them repaired at Babbit Bearing in Syracuse. I've had allot of their stuff go through
here mostly for vintage Indian and Hendersons but also some others.

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Truckedup
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Re: Vintage motorcycle main bearings

Post by Truckedup »

Thanks for the help.......The bike owner has talked to the Ariel clubs and several parts vendors...
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
BCjohnny
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Re: Vintage motorcycle main bearings

Post by BCjohnny »

If you have to make your own bushes, as said good ol' PB1 wouldn't be the worst choice ...... PB2 even

Get 'centrifugally cast' tube if you can, it's superior in many ways to solid bar

Generally stay away from the Aluminium bronzes, some aren't as sacrificial and can wear the shaft more than the Phosphor bronzes

Also be very wary of sintered type 'electric motor' bushes ....... they can and do work well in some applications, but you have to make sure you get the 'purer' bronze ones not doctored with Iron and the like, and even then they can 'swage out' under load ...... it can all be a crap shoot really so probably best avoided
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