omahapredator, did you install over-sized valves ? If you can turn your engine over easy then you have a bent valve. but bending two valves is very common when the valve to piston clearance in not set properly.

 

Actually, if the timing chain jumped, that's when the valves bent. Not at time of assembly. You're running some crazy compression, right omahapredator? I would go with the way powerslider said to check for leakdown.

 

cousin has a cylinder leak down tester but it says to run it at 100psi....is that too much pressure for the pred??? don't wanna blow any seals!!!!! the engine is hard to get past TDC when turning by hand!!! i went 1 mm bigger on the valves with a 3 angle valve job. but is easy to turn until you're coming up on TDC the it's a B*TCH!!! and the ONLY valves that are out of spec are 1 intake and 1 exhaust! how could 1 of each bend and not the other 2??? oh yeah and i'm running about 13.5:1 or more compression!

 

You'd be ok at 100psi. I'd suspect you have a higher number with the engine running. Dunno how you only bent 2. Maybe you bent more. [img]i/expressions/face-icon-small-sad.gif[/img]

 

You won't blow any seals, your running way more pressure than that anyway. From your last post if it's hard to bring up to tdc on the compression stroke then you do NOT have leaking valves, set the clearance and run it. I keep a record of my cylinder pressure (compression psi) for future reference and check it periodically. When it starts to drop off from normal you know it's time for a rebuild..........
Another thing to do is pull the plug out and roll it over, it should turn easy...

 

it is easy to turn with the plug out but getiting to TDC is still alittle bit of a chore...LOL

 

OmahaPredator ,

As you requested in another thread I am replying to this thread . Here are my thoughts on the matter.

1 If you have bent valves your quad won't even start . Don't take the head off .

2 Reset your valve clearance to Mr. Nicholas' specifications . Clearance spec for his cam may be different than factory specifications .

3 Valves generally work there way tight (valves receding in head) The only way the get loose is if the cam heel wears or the bucket and shims wear ------> not likely -- you can ussually see this .

I would call Mr. Nicholas , get the correct valve specs and set the valves accordingly . Then I would put a few hours on the quad and then recheck the clearance . I don't think you have a big problem to be honest . Like I said before , if valves were bent the bike would not even start .

NOTE --> I don't know the folks at Nicholas Cycle Racing , I am certain from their reputation that they do a fine job .

 

thanks for the reply rick....will do that!