Vito's power pistons

[sandornothing]

The website claimed 5-6 HP gain over other brands. I went with the cast instead of the forged for durability. Ive used Wiseco the last two times but i thought i'd try something new. Anyone have any stories to share before i install them?

[Nightrider]

Those power pistons skirts are very short.If your running clearance is somewhat excessive,then do not run them.I recommend a maxim of .0027-.0029.Anything more and they will really wear out fast.Not to mention they will rattle more when cold.

 

I know they bump up the comp about 12-15psi.They really bring in the midrange hard.Add a set of fatty pipes and vforce reeds,+4 timing and a lightened flywheel.Thats how my 01 is setup and it just tears up the woods.

Edited May 24, 2005 by Nightrider

[sandornothing]

Nightrider, theyre going into a fresh 65.25mm bore so i should be good right?.

 

Are the "Power Piston" skirts shorter and weaker than stock pistons? Because im doing my wifes bike right now too and her bike has never been opened up and it is a 2000 with about 100-120 hrs on the stock pistons? Her cylinders are fine, she's getting a .010 over bore and some Pro-X's just for the sake of starting fresh.

 

I knew i should have just stuck with Wiseco, but i got chumped for 5-6HP claim i guess.

[badassbanshee479]

Nightrider, theyre going into a fresh 65.25mm bore so i should be good right?.

 

Are the "Power Piston" skirts shorter and weaker than stock pistons? Because im doing my wifes bike right now too and her bike has never been opened up and it is a 2000 with about 100-120 hrs on the stock pistons? Her cylinders are fine, she's getting a .010 over bore and some Pro-X's just for the sake of starting fresh.

 

I knew i should have just stuck with Wiseco, but i got chumped for 5-6HP claim i guess.

373520[/snapback]

 

I would stay with the wisecos I ran a set of the pro x's in my yz 125 and it locked up when it got hot after you let it cool down it would start right up then get hot and lock back up again changed over to wiseco (which I ran for years before trying pro x's and never had a problem, la sleave redid the jug and set the clearences so I am not sure if it was there fault or if the pistons just sucked but when I changed it over to wisecos it ran great

[Nightrider]

Piston clearance must be checked.A fresh 65.25 mm bore from one machinist will be different from another.Quality of work being the key.

 

The power piston skirts are alot shorter,but just as thick.

The vitos pistons have a very thick dome,good for higher compression(I ran 180psi) and durability,the down fall is the weight.They are almost as heavy as forged pro-lites.

 

The Namura cast pp is a very light piston,noticeable lighter than the vitos cast power piston or wiseco pro-lites.I would not recommend them for anything over 140 psi.For near stock compression and porting,they work great.

Edited May 25, 2005 by Nightrider