I thought about the Raleigh 20 BB

People dont want to modify the frame

So youve got to use the standard BB. With cottered cranks.
Or get a difficult to obtain BB and a set of expensive BB cups.

I thought there must be a better way.

So I looked in my box of axles.
Theres a cartridge from a bike that had plastic BB cups on both sides.
Id butchered the BB cups to get the cartridge out.
This is a good fit in the standard BB cups.

I cleaned the BB shell and the cups
Screwed the left cup in all the way, to clear the paint from the threads.
Then test fitted the BB
Seems to be fine.

I tried cranks on it.
Had to select ones that are shallow on the axle.
So older cheap ones wont fit
But these ones are ok.



Dont know if the cups will stay put. Might loctite them in

Is this a bodge? Or is it ok?