Hey All,
I have an 2006 LYZ400 that is going to need a top end rebuild within the next week or so. And since I am at it, should i replace the stock piston with a Wiseco forged?

I don't race the quad, however I do like power (who doesn't).
Is there really a noticable power increase? More maintenance?
Should I go higher compression or stay stock?

Just wondering since I am going to have the work done anyways.

Thoughts?

Thanks in advance!

 

It needs a rebuild already? That's actually pretty rare believe it or not for a non-racer.

Either way.....the problem is if you go higher compression you are going to get close to where you need to run race fuel. The stock compression is already 11.3:1 so going up to the next piston which IIRC is 12.4:1 or something might require like 96-97 octane.

There is a chart on the wall at a local speed shop here and 11.0-11.5 is listed as 90-92 octane minimum. I think once you get to 12.0 you are getting into the 95-97 range so pump fuel might not work well.

It depends on what compression you are talking about.

 

Well, I am guessing it needs a top end rebuild. At least that's what the shop says.
right now the only way to start it is jump starting it by popping the clutch in 1st gear.

I will probably go with the standard compression. Just didn't know if I should go with an over-bore or standard.

Also, what are your thoughts on forged vs. cast pistons?

Thanks.

 

if thats the way it starts ,it needs a valve shiming