KZ 1300 Head Work

Tyler,

Measure the valves when you get it apart. The exhaust look pretty large in that picture. I have no doubt there's power to be pulled out of those heads. Some bowl work and throat sizing with a good valve job will likely wake up the ponies......What are the cam specs?

Larry, I haven't measured the specifics on my engine yet but from my manual and specs on available parts this is what I know.

Bore: 62mm
Stroke: 71mm
CR: 9.9 to 1
Head Chamber Volume: 27.1 to 27.9cc
Ex. Valve Size: 29.5mm
In. Valve Size: 34.5mm

This engine runs a domed piston. Peak torque @ 6,500 Peak Hp @ 8,000rpm (according to the manual anyways)

And some cam info from Megacycle

Intakes are 55% of the bore diameter so that's plenty. The exhausts looked bigger than they actually are. Those long runners are great torque makers but probably hurt peak flow somewhat. That 490-70 grind would make a nice drop in. L/D ratio would be better than same lift for a KZ1000. If you're not putting pistons in it, that's the one you want.

I am considering a 64mm piston, just a bit shallower than stock, not clearanced for a big cam.Supposed to be close to stock CR. Any bigger and I need to put overbore sleeves in the block, not something I want to get into. Not many carb options, so Im sticking with the stock set-up. Three, two barrel carbs, BS style Mikunis 32mm per barrel. Not gonna mess with a DFI conversion.