C90Club.co.uk

Hi all what big bore kit is best for my 50cc 12v lifan motor I have fitted to my Z50j

Thanks

Iirc72, 75 and 88cc kits would be available like these
https://www.shirebikes.co.uk/collection ... ke-up-kits
But contact ooracing for alternative kits, and try TB for kits like the tbw0928 (88cc) though the likes of motosyko.

Colin

Hi Colin

Thanks for the info I’m new to monkey bikes, would any 12v Honda style barrel fit ? I’ve seen so many kits available is one better than the other?

Cosworthwestt wrote: ↑

Fri Aug 20, 2021 8:35 pm

would any 12v Honda style barrel fit ? I’ve seen so many kits available is one better than the other?

No.
I've very little knowledge about these smaller sub 90cc units, but know the 6v and 12v stuff is defo different, and your restricted by the bore of you current crank casings and stud pattern, which limits the barrel skirt and piston size choice.
Hopefully one of the more knowledge gents will chime in and explain in more detail.

Hi. Most 12v Honda type barrels will fit,both Honda and most pitbike ones. But if keeping the same stroke/crank only the 72cc will fit,both 6v and 12v are the same barrel/fit.To go bigger you may have to strip the engine down to open the crankcase mouth some.But a lot of the copy engines all have the same case from 50 up to 110 so you may get away with out doing that. Other sizes you can go to are 51mm(85cc) and 52mm(88cc). I have in the past bored a 6v Honda C70 barrel out to take a 50mm or 51mm piston. This is more so on the iron barrels as they have thicker skirts than the alloy barrels with a thinner steel lines. In the past you could get pistons of a 70 size that were made to run with a 50 head,think in both 6v and 12v types.

steve g

Thanks for the info Steve and sorry for the delay in saying thanks. Work just seems to get in the way of playing with motorcycles