Top end rebuild

I am sending my top end from a 06 CRF250R to FASTHEADS in Utah to get a complete rebuild with the beryilium seats and new titanium intake valves. I was looking for anybody who has had work done by them and what they thought of it.


If you are dead set on keeping your titanium valves that might be the way to go. but if you want longevity I would go stainless. Check out

The cool thing with our heads is just put in the cam. Shim and go. Comes with heavy duty springs and titanium retainers. And for $575.

Wow that's a good price.

On my 07 crf250r. Right intake valve keeps sticking open?? Had top end rebuild last year with stainless valves and matching springs went to adj valves and after all valves adjusted perfect few times kicking check them again and right intake I can fit my biggest shim on my feeler gage set and still lots of play

How big of a shin were you getting in there?

.022 and moving very easily. Get way bigger in no problem.

If I can get it to go back in if I kick it over but def worried on bending the valve if its not already. Ordered new head gasket. Thinking I need to investigate further?

Are you checking valves when timing marks are lined up on right crankcase and the intake lobes on the cam are facing the rear of the bike? It just seems crazy you can get .022 under the cam lobes with them pointing back and timing marks lined up. Plus the marks on the cam gear are located correctly on the cylinder. See pic I sent



I also wonder if your valve spring is worn out and not keeping the proper tension on your valve? It sounds wierd but a possibility. Did you replace them when you rebuilt it awhile ago?

Yes on the timming marks and its only on the right intake. All other valves stay perfect. I did change the springs to a heavier ones to make the weight for the heavier stainless valves in I did at the start of season last year. It does Seem very weird and thinking I got a bent valve that keeps hanging up.

Since your using stainless steel intake valves, they are not designed to rev as high as the titanium ones do. Your rev limiter is electronically set. Plus its,setting was set with stock titanium valves. I wonder if you hit the rev limiter and it caused the valve to float or cause something else to go wrong and that's why you have a excessive gap or .022

I think the stainless intake valves just can't take the rpms that the titanium ones do.

Ill be ripping the head off in couple hrs so I guess ill find out let ya know but ya seems very weird. But as far as valves floating I was told that can be the case going stainless but only if you don't get the heavier spring to make up for the weight and that solves the problem

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