Moped Small end Crankshaft Bushing

I now know that I need a full topend rebuild. What do I do to replace the bushing in the small end. I don't want to get a new crank so I need to know how to replace the small end bushing. I know how to replace everything else.

Re: Moped Small end Crankshaft Bushing

Overpriced Parts /

Hmm having the puch factory tools it's not that hard but you don't have them so you need to press out the old one with a c clamp or vice and a small socket or something that just fits in the crank then press in a new one, then ream with a adjustable finish ream taking a little of the brass at a time until the piston pin fits perfect . There is a problem that aftermarket bushings are too small/loose and don't have a oil hole but its easy to drill a new hole though.

Try to get on flea bay nos puch bushing for best job.

Get two cause you will prolly ruin at least one if it's your first time

I did several with good results using nos puch bushings.

Re: Moped Small end Crankshaft Bushing

Oh you are the one i talked to about the worn out bushing. It turns out that my bushing and piston pin are in perfect condition. Im replying to this after i tore the topend apart. I turn the flywheel guickly to the left and right with the crankshaft bear and i still here a clunk but it sounds like it coming from the back half of the cases. any suggestions on what it is now?

Re: Moped Small end Crankshaft Bushing

Overpriced Parts /

Worn main gear/bearing, worn clutch bell or clutch bell bushing, too tight of a chain, A little clunk is ok.

For giggles put your piston pin back in the piston on crank evenly like the way it's in normally and move the pisto around and see if there is any movement at all . You can't have any

Re: Moped Small end Crankshaft Bushing

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You could check for play in the bottom crank bearing too

Re: Moped Small end Crankshaft Bushing

Can there be any side to side play on the piston?

Re: Moped Small end Crankshaft Bushing

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Not much play from c clip to c clip

Re: Moped Small end Crankshaft Bushing

Ya there isnt much I think im gonna stop being cheap and rebuild the whole thing over the winter.

Re: Moped Small end Crankshaft Bushing

Overpriced Parts /

Best solution ^^

Re: Moped Small end Crankshaft Bushing

Right then i can eliminate any other future problems. Thanks for your help!

Re: Moped Small end Crankshaft Bushing

Jake D, i'm in the same position as you and need to push out old bushing and press/ream in new one so if i do it right ill let you know how it goes/ give you tips if i find any of the best way of doing it, once again thanks Ken Roff for keeping my bike alive !

Re: Moped Small end Crankshaft Bushing

Yes please send me a personal message when you are finished. Some pics would be nice too.

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