750 or 800cc

[grubscrew]

At what point does it get too thin on reboring the barrels (base of) for it to be a problem or are there modified cylinders  (ie Nanni) with thicker bases so they dont end up in the sump in pieces.

[DEYAN IYI]

No, you can't rebore it even to 700cc (80mm). But its possible to rework the original cylinders (at least to 80mm) . Take a look HERE!  It's for 700cc with Bis pistons (and crankshaft).

Modifying 126 with Beetle's parts HERE! Again needed Bis's crankshaft! Not a good idea to use 126 conrods... (as the ones in the article). Also they say that each piston-rings-pin group is 100gr. heavier than the original. So, for sure is better to buy something decent.

Regards!

[hudsonhenry]

Ad Deyan says, even on a 695/700 rebore the cylinder walls get dangerously thin and it's not unheard of for chunks to break off and fall into the crank case, which can get a little messy.....

You can get kits which include new pistons and barrels with thicker walls, you will have to ge the crankcase bores opened up to fit these.

Nigel

[grubscrew]

Ad Deyan says, even on a 695/700 rebore the cylinder walls get dangerously thin and it's not unheard of for chunks to break off and fall into the crank case, which can get a little messy.....

You can get kits which include new pistons and barrels with thicker walls, you will have to ge the crankcase bores opened up to fit these.

Nigel

Thanks guys for the info. Michael.