There should be an english thread on both sides so the crank arm and chain ring should come off, behind the chain ring should be another threaded bearing holder similar to the one on the lhs.

Bearings should be old money so 1/4", replace all after a degrease and clean.

 

Crank & chain ring might be one piece also may be rusted on ? Try plenty of penetrating oil and tapping off or apply the heat snd cooling method to see if it will budge.

Thanks! So crank and chain ring should just pull off like the other side so I can get to the other bearing? Its very tight. Might have to get a puller of some sort....

I like your project, good luck.

Most so called 'advances' to bike technology make me feel 'so what?', but I'll certainly be happy if I never have to deal with a cotter pin chainset again.

Thanks! So crank and chain ring should just pull off like the other side so I can get to the other bearing? Its very tight. Might have to get a puller of some sort....

LH thread on the drive side.

It is most likely rust holding the crank/ chain wheel on esp as the cotter pin is out. Have to admit I hated cotter pins and still have the scars on my ankle from 50 years ago as a kid.

Edited June 24, 20223 yr by Nealh

So I got this far by simply unscrewing the LH side of the bottom bracket assembly, surprisingly easily! How does the shaft come out though???

It is most likely rust holding the crank/ chain wheel on sesp as the cotter pin is out.

 

If there's nothing else keeping it on and it's stuck with rust, and you are completely stuck having tried penetrating oil, applied heat/cold, tapping and time, and you've exhausted all other options... you may have to do as I did? Find a plank of scrap pallet wood, drill a hole large enough to securely hold a metal butt of some kind (I used a ruined crank extractor), stick that into the hole in the plank, so that it stands vertical. Then place the shaft over it and carefully hammer around the shaft on the other side, until the shaft comes out. At least, that's what I was advised to do by the 100 year wizened old local bike shop Yoda: "If I may make a suggestion? Place it over a metal butt of some kind, and hammer like hell!" He also said because I wasn't an existing customer, he couldn't find time to do it for me. Said he had too much work on anyway - I'm certain he had a puller. It took about two hours of alternately tapping and hammering like hell to get that baby out! Do hammer carefully. I didn't have a wooden mallet but that would probably be a more appropriate tool than the claw hammer I used. Solid gold advice that was, from the bike shop Yoda.

Edited June 23, 20223 yr by guerney

Not tried heating yet, so that's the plan today as the next step thanks!

Well, it's out. A bit battered and bruised - and the bike too!

Hi again all.

 

Holidays and work have intervened, but hopefully back on the project now.

 

So I have taken out all bearings and purchased replacements. Will start to clean up the frame and parts next, but also need to spec and purchase the motor and associated parts so I can plan the build around. I would very much like to use a front Bafang 250w hub in a road legal set up as per previous posts. Ideally ready built into a polished ally rim as having one laced is going to cost me around £70 at the local bike shop, but all I have seen so far are black. The kits I have seen so far wont really suite either as I need specifics like seperate magnetic motor cut off sensors for the brake system, not new levers, and (the tricky bit) a suitably thin battery with enough power to do 20-30 miles on a charge. (A bit less would be an OK compromise for a slim unit.) So open to suggestions for the parts / battery, any UK dealers you can suggest would be interested for the various bits and pieces?

 

I have been quoted for the slim KinstarBattery 36V 10.5AH with Panasonic 18650 cells $168/pc. and shipping cost of 2pcs to UK $233. Maybe one would suffice. Will it even take the discharge load though?

 

Thanks!

If one wants a specific rim then a wheel build is th only option.