KZ1100 Wiseco 10.25:1 compression piston kit

No eBay APP ID and/or Cert ID defined in Kunena configuration Would the Wiseco K1171 piston kit (see below) be a wise investment for a 1982 KZ1100 J-engine with 75000 miles, which has not had the bottom end rebuilt or reinforced with HD main studs?

Are the associated compression increases hard on these motors, or were they built to take the pressure without issue? :whistle:

Have built loads of these engines with just the Wiseco kits as part of the rebore and no other changes with no problems.
At 75k miles I would replace the camchain while It's apart though if it hasn't been done already and take a look at the camshaft shells etc too.

zed1015 wrote: Have built loads of these engines with just the Wiseco kits as part of the rebore and no other changes with no problems.
At 75k miles I would replace the camchain while It's apart though if it hasn't been done already and take a look at the camshaft shells etc too.

How much does it cost to have a cylinder block bored for a kit like this?
I'm concerned that the head gasket in the kit is intended for later GPZ1100 (83-84) engines, which do not use the four O-rings (having no recess in the block surface for them), to seal the oil passageway through the gasket as mine (1982) does.

Has anyone modified an earlier 1089 cylinder block, by filling-in the O-ring recesses?

I'm in England and pay around £140 inc vat for a over bore and plateau/cork hone .
That price includes taking the bores out more than the one size that is usually required.
As for the 'O' rings, Just fit them as normal or do as I do and turn up some alloy blanks and press them in to fill the groove .

Just my opinion, but I wouldn't overbore unless necessary. First choice for overbore would be with Kawasaki pistons if available (and affordable). High compression will make the engine more prone to detonation in hot conditions. It might mess with the carb jetting a little too. The liners get pretty thin with over bore kits so the long term seal integrity might not be as good as stock either.

I'm going through a similar question with my 750/4. Even bought the big bore kit but now second guessing. Not a fan of taking the liners out to paper thin proportions. Not looking forward to rejetting either. I wish OS Kawasaki pistons and rings were more readily available.

Thanks Nessism...
How many $thousand$ are spent to achieve some perceived level of performance, which may already be hidden behind the partial turn of a fuel-mixture screw?
Your point...well-considered.