NEED MORE POWER!

[Bruce_Blaine]

Wouldn't you need to get your domes cut for a 4mil?

[J-Madd]

Don't get your hopes up on making that a 4 mil. You'll more than likely have to start over with a set of cylinders cast for a +4 mil stroke. And in the 68 mm bore, you run 573 series (Blaster) pistons, not 795.

[sprinklerman]

If its been ported already, you might not be able to run a stroker crank. Port timings could/would be off. If it was mine, i'd take the head off,measure the ports from the top of the deck (in MM),and then call one of the sponsors here.

I'd recommend leaving Jim @ Passion Racing a message and see what he can do with what you have. If it was ported by trinity,there might be some room left for improvements.

[Wicked ATV]

so all i need to run the 4 mm stroker crank is weisco 795 pistons? what is the difference between those and the vitos 68mm pistons i just put in it?

 

 

If you do a +4mm with 110 Rods you can keep using your Vito's Pistons. Should be a drop in situation but you will have to recess the domes for the added stroke. Don't worry too much about the port timing. Sense your running Power Valves they will help compensate for the taller exhaust ports if been moved. Thou I'm going to take a stab they've not been raised sense it's a std stroke with Power valves. the intentions of that Cylinder is to maintain as much low end possible by using Power valves.

 

Now if you got a +4mm 115 rod crank then you'd be using the Blaster Pistons 573MO6800

 

Not knowing what pipes you have or carbs which i didn't seem to see. But with the right parts you can make any where from 75-85HP with your setup and you'll have more than enough Bottom end with a +4mm and the Power Valves.

 

If you'd like more info I'd be more than happy to take a look at your cylinders and get you straiten out. I've done more than enough work on Power Valves set ups on Cylinders. My Street bikes all have Power Valves. you can see in my signature the bike up front the Red Banshee has T-rex with PV's and my 500 Street Bike has 4- Power valves on it

 

So don't get rid of your cylinders they are definitely something you can make work

 

Roger