Hi   Purchased a Sherpa m80 100 cc , on ebay few years ago ,just engine , Installed new piston please look at pictures ,small head ,don’t see any 100cc  , on m80 ,, what you think

That doesn't look like an M80 engine to me.  M80s were all 250cc.  The cylinder heads on these are held on with 6 fixings not 4.  The ignition side case is too rounded for the M80 as well.

I think this is a 4 speed engine and the number has either been "restamped" or is a badly labelled M8 Engine from a Metralla.  These have the same cases as in your photos.

Attached are 2 pictures of an M85 engine which is the same as an M80 engine.

Edited December 18, 20196 yr by rcgods

Thanks  rcgods , this engine has  me going back forth , I thought it was model 8   Then , some guy said Sherpa ,  maby a mis stamp   Not like 6 bolt   , round case  , small spacing head studs ,  ?  Model 78 Sherpa ? , lobo , or special order engine , some one might have the same , really just 100cc,larry

Hi found a 80 Sherpa campion 1970 100cc , in Chorley  uk , under supermotos.com its blue white silver frame listed for sale  , I just need to look a little more  , Larry

7 hours ago, larry s. k. said:

Hi found a 80 Sherpa campion 1970 100cc , in Chorley  uk , under supermotos.com its blue white silver frame listed for sale  , I just need to look a little more  , Larry

That bike on that website is definitely a Model 80 Sherpa.  The tank unit is should be a fibreglass slimline unit.  It has Homerlite (aluminium)  tank that was fitted to UK model Sherpas around 1973 as fibreglass petrol tanks were banned in the UK.

All Model 80 Sherpa engines are 250cc (244.29cc to be precise).  In fact until the Model 92 Sherpa T all Sherpa T models were 250cc (other capacities followed both higher and lower).  Attached is a scan (taken from another website) of the Model 80 brochure.

The only Sherpa models that were less than 250cc (prior to the Sherpa T) were the Sherpa S and Sherpa N that the Sherpa T was developed from.

Edited December 19, 20196 yr by rcgods