Trouble finding 51mm bottom bracket?

davla

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Oct 22, 2018
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I'm using a Chinese aluminium Schwinn copy frame for my project but can't find a press fit bottom bracket for it. Can anyone point me in the right direction pls? I'm in the UK btw

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IMG_2439 2.JPG IMG_8651.JPG IMG_3095.JPG
 
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davla

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Oct 22, 2018
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Cheers guys....I discovered it's basically the same as an old style BMX 1 piece crank set up, so I should be able to find a set on ebay like you say.
 
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Ludwig II

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Jul 17, 2012
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Try my mate Doug Pinkerton in Redditch. Vintage, rare and specialist bike repair and construction. He'll even do you a Dursley Pedersen if you ask him nicely. If he can't get you one, he knows a man who will. Phone 0777 842 9313 after tomorrow evening, he's on a small break with his wife right now.

Where are you anyway? I'm in Brum.
 
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davla

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Oct 22, 2018
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Hi Ludwig, I'm in Ashford, Middlesex/Surrey/West London. I think I've got one of these cranks on another bike that I don't use, if not I'll give Doug a shout

UPDATE - All sorted, it took all of about 10 minutes to remove crank & bearing assembly from one frame and fit to the other
 
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davla

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Oct 22, 2018
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I'm just using an 80cc/66cc Chinese engine. I picked up the whole engine kit for 88 quid from ebay and have replaced all of the cheese screws with stainless Allen bolts. I'll also whip off the head and make sure there are no air leaks. I'm using a 40t Sportsman rear sprocket and will probably stick on a better carb and modify the exhaust to run straight through to the rear wheel. I'm waiting on the wheels to finish the dry build and will then get the frame powder coated black and will build up properly. It's been very straight forward so far so fingers crossed.

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davla

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That’s a good question, I have no idea! It would be nice to find a disused running track or small airport runway but I need to have a look around. I might try and get ‘single vehicle approval’ from the DVLA but don’t know how realistic it is. Where do you ride yours?
 
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Ludwig II

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It's part way through construction. I haven't been able to get work done for various reasons for most of this year. I am short cutting legality by using the fact it's based on an old Raleigh with exempt paperwork to have it on the road.

The SVA offers 2 levels of moped, if you go for 50cc, 1kw Low Power Moped status, the rules really do fit a motorised bike. 1 headlight, 1 tail light, no indicators or brake light required. Tyres only have to be good, sound and have decent tread depth, no speed rating needed, about 30(K)ph max speed. All controls operable from handlebars. Basic common sense stuff. If you go for the ordinary level, you have to have all the bells and whistles a commercially sold moped needs.
 

davla

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Oh ok, thanks for that. I’ll look into it a bit further and might stick a 50cc engine in it in that case as it’ll give me more opportunity to ride it
 
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davla

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Oct 22, 2018
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I loosely assembled the bike today before painting the frame and found a few issues but nothing that I can’t resolve. I tried Kenda thorn resistant tubes but they don’t seem suitable for 2.35 wide tyres so have ordered some different ones.

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