Big Bore Kit

Hi to all.when talking about a big bore kit what size of pistons will be big bore on a 1300?

The kit I have to use is 2mm bigger than standard.

Hi Dinosaur
I have used one of these kits without any problems. Machine shop manufactured outer tubes to fit around piston sleeves at the bottom of the barrels so as not to end up with an oval bore after machining. There is not much meat left on the piston sleeves after machining but this upgrade has worked well. Lots more torque and low down power. Money well spent.

Forgot to mention. bought this kit.
78-82 Kawasaki KZ1300 1370cc Bigbore Piston Kits with Head Gasket KZ1300BB
You will find it on ebay.

Hi,
I was also thinking of going for a big bore kit but wasn't sure which one to go for, I read some time ago that someone used 750 pistons to take the cc upto 1500, but that seemed like a lot of work.
So 1370cc seems to be the usual size but not sure what kit to go for
I've seen on eBay a kit from japan I think from CruzinImage, ( I think can be bought from zpower as well) which isn't too expensive, but not sure on quality.
Another kit was by Forseti, which seemed to be advertised as high quality.
I've also seen a kit from the USA but can't remember the supplier on eBay which was priced at $500 (I think )
so has anybody used any of these and any problems?
It's been said that you should always use the original head gasket, I guess in this case you can't, so has anyone had problems with leaking head gaskets?
Thanks for any info, Pete.

I've just bought the Cruising image 1370 big bore kit from Japan. Ordered it on Sunday night and it was delivered on Wednesday with just the standard delivery option.

The quality looks reasonable. The pistons feel very light but I don't have an original to compare against.

Will be a while before I strip the barrels and get the machining done.

here's a picture of one of the pistons: