leakdown test

 

I agree on a leak down test, but I wouldn’t be in a rush to do this. There is a better than average chance it’s a clogged fuel filter on the end of the fuel pump in the fuel tank. Happens to many a rider. You can buy a new pump and filter on Amazon. About $80. Polaris is like $435. Easy to replace.
since I have seen and heard of tons of Razors with this issue I would do it first.

 

... tested for fuel good ...

Agreed to above if this didn't mean fuel pressure test was good

 

I forgot to add I did put a new fuel pump in

 

30psi sounds kind of low. Is it possible the rings are going bad?

 

No holes in piston, so you took it apart? Or just bore scope?

 

Just bore scope

 

I have a 570 that was hard to start and finally the rings got bad enough that it wouldn't start. Did a compression test and I want to say it was getting only 30psi.
About 2 years ago the engine had the spark plug basically explode. We scoped the cylinder and didn't see any debris inside so we put it back together and put in a new plug. When the machine was cold it was hard to start. After it warmed up it wasn't bad. After time we think there was some porcelain in there that wore down the rings and possibly the cylinder walls.

 

Sheared a flywheel key?

 

I’ll have to check the flywheel key I have a leak down tester on order waiting for it come

 

I just saw you said timing was good so I doubt fly wheel key
If it's 30 psi in both cylinders I would say a blown head gasket between the cylinders

 

That’s what I’m hoping for would be easiest cheapest fix. I’ll post once I get the tool in

 

I was able to do leak down. Test today pto cylinder on tdc on compression stroke I’m getting air coming out the intake. Guess just have to pull the head off see what it looks likes

 

Sounds like intake valve but you said valve clearance is good
What about the other cylinder?

 

Just checked other side. Getting same air coming from intake valve.
Here’s a pic of the cam timing it matched the timing mark on the flywheel

 

My eyes are bad lol. Shouldn't the "I" for intake be across the "E" for exhaust?
Been awhile since I did a valve check
Do you have the old style hydraulic cam chain tensioner? They've been known to fail and chain jump teeth
What happened to the lil cowboy? Cool pic

 

I changed it out with a manual one I’ve had it jump timing before and would idle but wouldnt go past 2k rpm

my timing is how it shows on the picture you sent

 

any luck?

 

Had a friend come help with it double check timing everything was good put a camera in the spark plug hole again we thought we saw the cylinders all scored up we took the head off. Cylinder walls look new still see the original crosshatch valves look good flipped head upside down put gas in the dome to see if any gas would leak thru valve and no leaking I do t know what’s wrong. Head gasket was in good shape no noticeable damage

 

With 30 psi on both cylinders, consider a cylinder leak-down test to pinpoint where the compression is lost. Check the head gasket, piston rings, and for any vacuum leaks. A leak-down test can give you a clearer direction.