Converting a 28tpi to 24tpi One Piece Crank
01-21-09, 04:44 PM
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Converting a 28tpi to 24tpi One Piece Crank
I recently bought an old ass schwinn frame that has a one piece crank, but it is 28tpi. 24tpi parts are much more available, so I was going to convert it with a new kit from Harris Cyclery.
My question is how hard is it to remove/replace the pressed in cups? Is it as simple as using a block of wood and a c-clamp or is this serious machining?
My question is how hard is it to remove/replace the pressed in cups? Is it as simple as using a block of wood and a c-clamp or is this serious machining?
01-21-09, 05:58 PM
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I recently bought an old ass schwinn frame that has a one piece crank, but it is 28tpi. 24tpi parts are much more available, so I was going to convert it with a new kit from Harris Cyclery.
My question is how hard is it to remove/replace the pressed in cups? Is it as simple as using a block of wood and a c-clamp or is this serious machining?
My question is how hard is it to remove/replace the pressed in cups? Is it as simple as using a block of wood and a c-clamp or is this serious machining?
Dan.
01-21-09, 08:52 PM
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what is this 'kit' you speak of? Personaly, if I could buy a 28t.p.i. BB I would versus swapping out the crank.
But, if you do decide to swap it out, as noted in the post above mine, its easy.
But, if you do decide to swap it out, as noted in the post above mine, its easy.
01-21-09, 09:55 PM
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https://harriscyclery.net/itemdetails...0&catalogId=39
https://harriscyclery.net/itemdetails...7&catalogId=39
Its much easier than finding 28tpi parts for the nasty rusted up chainring/crank that came with it.
01-22-09, 06:28 AM
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Not a kit per se?
https://harriscyclery.net/itemdetails...0&catalogId=39
https://harriscyclery.net/itemdetails...7&catalogId=39
Its much easier than finding 28tpi parts for the nasty rusted up chainring/crank that came with it.
https://harriscyclery.net/itemdetails...0&catalogId=39
https://harriscyclery.net/itemdetails...7&catalogId=39
Its much easier than finding 28tpi parts for the nasty rusted up chainring/crank that came with it.
01-22-09, 01:08 PM
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I just replaced the ashtabula on my super sport with a modern euro square taper BB, using an adapter from A.E. Bike, Harris sells them as well although they only carry black and I wanted clear Anodized.
https://aebike.com/page.cfm?PageID=30...ils&sku=CR0500
Popping the cups out was no problem lay the bike on a towel or something on the floor, get a big ass scredriver or something, spray a little WD40 around the cup from the inside the BB shell and use a mallet to to tap the screwdriver right where the cups hit the shell being carefull not to damage the cups, with a couple medium hard wacks all around, they should pop out intact. then I just greased up the adapter and installed per the instructions
https://aebike.com/page.cfm?PageID=30...ils&sku=CR0500
Popping the cups out was no problem lay the bike on a towel or something on the floor, get a big ass scredriver or something, spray a little WD40 around the cup from the inside the BB shell and use a mallet to to tap the screwdriver right where the cups hit the shell being carefull not to damage the cups, with a couple medium hard wacks all around, they should pop out intact. then I just greased up the adapter and installed per the instructions
01-22-09, 02:18 PM
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You can go either euro or 28 without spending much. I stayed OPC, I spent like $30 for new crank/chainwheel/bearings/cups. If you've got newer spares laying around, may as well convert. Conversion kit you can get for like $20-
https://www.google.com/products?q=con...oducts&show=dd
To get the cups out find a screwdriver that says "not to be used as a chisel" and get a hammer..
https://www.google.com/products?q=con...oducts&show=dd
To get the cups out find a screwdriver that says "not to be used as a chisel" and get a hammer..
Last edited by riva; 01-22-09 at 02:22 PM.
01-22-09, 06:39 PM
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