Z1OwnersClub GB

Further to me Lawson in the Projects section.... today I discovered SIZE is EVERYTHING
Me bike only has 72mm barrels & pistons... not the 78mm (1260cc) as it was advertised

So, its either had an engine swap (heads OK tho) or just barrels..

To establish whats what, can anyone tell me what the casing mouth size is for a std engine - where the barrels fit



Mine are 84mm diameter.... but can't tell if its been opened out - it don't appear to be

Piggy I'll check a set of cases later and let you know.
Looks like you've got standard 72.5mm,1089cc barrels and pistons then
Should have kept them 34mm Flatslides

from your pic it looks like the crankcases have been opened out for a 1260 or bigger. i would ask steve debben to have a look

Pork Scratching my standard crankcases measure approx 80mm diameter.
With standard crankcases you can go upto 75mm pistons,1170cc without any modifications,76mm (1200cc) and upwards require crankcase boring.

Jack..... I need some advice pleeze....

The barrels are 998 with stock liners, bored suit to 72mm pistons, looking at the liners, this is about max

Having checked the rings they need replacing..... ££££££££ What options have I go for using different std barrels & liners to take out to max for biggest pistons... keeping me 84mm cases as they are....

If I'm gonna fork out on a new Wiseco/MTC piston kit, may as well go big as poss

The Kawasaki 1100 block (1089cc) can be bored out to 75mm (1170cc)
Any bigger will need new cylinder liners and the crankcases boring,which you've already got.
Personally I'd only go to 1170 for a road based bike and if I was going any bigger then I'd go for a proper big block,etc and all the ££££$$$$ that it's going to cost.
Obviously more bike bitz will mean less BISCUITS

Pigford, the 1260 kit originally supplied for that bike would have has KA750SL liners , these have an outside diametre of 83mm, so the crankcases have been bored to 84mm. looks like at somepoint in the past somebody has robbed /replaced the 1260 kit and fitted another set of barrels with a 1076 Wiseco piston kit which is the safe maximum size for the 998 block. You have 4 choices, leave it as it is, buy a 1089 blcok and go 1170, fit larger liners and go 1260, buy a big block and go 1327cc or bigger. Regards, Steve

Cheers Romeo.... probably have to go the 1089 - 1170 route
Got anything laying round your gaff

Might well do, We have a engine build at the moment that is going big, I will see if this block is going to be up for grabs

Corrr.... soopa doopa..... Best stock up on biscuits, coz you probably won't just "give it to me"

If you're good, I'll even let you fit it