TOPIC:

I’m thinking I might try something new with my potential upcoming overbore, but I’m not sure how much I’ve got to work with. I know the Wiseco 810 is 69mm, and I’ve heard of an upper 800s engine, but I don’t know if that was stock sleeves. I may as well say that I’m hoping to use some Z800 (71mm) pistons...but I’m prepared to find something a bit more reasonable if I must.

You will have to resleeve. Also check wrist pin diameter and pin height.


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I don't know what the sleeve OD is but it may be possible to do Nikasil coating and ditch liners all together.

if this is KZ750 / 4cyl you can bore stock sleeves to 810cc but you better have them centered perfect, I done many 750 turbos to 810 sleeves are so thin you can squeeze enough to distort them, I ran this set up 20,000 miles on my 750 turbo W/O issue ! I also had 750 / 4 drag bike with 810 kit an ran for 7 seasons W/O issue

Thanks for the input, everyone. I'll put this idea on the far back burner.

The stock KZ/GPZ750 liner is 71.49mm OD

Boring to 69mm for 810cc leaves a very thin liner wall that can distort easily.