crf valves in a trx. does it work?

[nynetwo9]

in the process of rebuilding my 450, fresh piston, cam chain and valves. I was told to by a couple ppl to get crf 450 valves becuase they were titanium and they where better. was told they fit. I haave a 2005 trx so I ordered 05 crf valves. When we put it together last night we ended having the smallest shims we had in it and it was still out of spec. These shims were smaller than the ones used for my old worn valves. (i work at a dealership so I had access to multiple shims.)

I just bought crf valves, should I have gotten something else to make these work? Buckets etc? Or cant you use them at all? I dont wanna have no adjustment left on brand new valves.

thanks

[yfzfelix]

your valve seats are probably worn and need replaced, a new set of seats and your valves will sit lower and you will have more clearance and use a thicker shim, I think you will also need to use the CRF valve guides, I thought the CRF valve stem was a smaller diameter than the TRX valves, maybe I'm wrong, did you check your stem to guide clearance ? I know they work, my son runs CRF valves in his Dasa head, Steve

[JH Racing]

The intake valves drop right in like said above you need new seats if you do not have clearance. If your head is a 04-05 you need ex valve guides plus having your seats cut for +1 if you ordered earlier crf ex if you ordered 06+ they are 30mm like the trx and you will just need guides on a 06-09 TRX head the ex valve guides are the same as a CRF but the earlier CRF ex valves will require the seats to be cut also

[nynetwo9]

i have an 05 trx and I just ordered the same yr crf valves. 2005 as well. Well that sux. so should I just buy trx valves or buy the crf valve guides.

[dran714]

well since you need new seats installed and machined do the crf guides and youll have big exhaust valves with the ti intake saves from trying to sell the crfs