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Yamaha Problem with intake valves

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Hello all. I would like to start off saying thank you for all the help thus far on this forum. You guys and ladies rock. Now to the part that has me pissed off.

I am having trouble with my head. I recently installed new intake cams and also had the head ported and polished, valve job and also installed a hotcam on the intake side of the head. I installed the head into my 2004 yfz 450s, put the timing chain on made sure everything was lined up correctly as far as the notches on the cams with the mating surface of the head and the mark on the magneto in the view hole. I checked my clearance intake and exhaust and had .20 on the exhaust side and .15 on the intake side with the hotcams. The .15 is the correct valves lash for the hotcam. Now, after everything was installed I connected the tensioner back to the quad and released the push pin and it done its job on the timing chain. I put a 17 mm socket on the crank and turned over the engine to seat the new shims correctly a couple of times. The quad turned over past the exhaust correctly and then all of a sudden as the intake lobes pushed down on the valves lifters it bound up and would not completely go a full turn on the intake side. Please help if any one is a yamaha mechanic or has experiance in this matter. I have taken the valves apart and reseated them and checked the shimms thinking that was the issue, NO. I am stummped and frustrated as hell. For some reason the intake valves are not fully compressing as far as I can tell. The engine does turn over with the old head on it with the cams installed so it doesn't mess the timing. Hopefully someone will have an answer or some suggestions before I go insane. Thanks to all in advance and look forward to talking soon.:lol::foul::lol::foul::lol::thumbsup::banghead::ride:

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Well I think I figured out the problem. There were 2 spring seats in the head on the bottom of the spring that sets aroung the guide seal. I am not sure how this happened but am pissed at the guy who done the work. He said his mechanic might have put the extra spring perches in the head. I am glad I took the valve springs out before I took it to someone to tell me what I just found out. I will let everyone know if anything changes and if it works like it's supposed to.

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Hahahahaha. I did figure it out. They had put the bottom spring perch from someone elses head in all three of the intake valve hole. I removed them put everything back together and walla. It spins freely and I also did set the torque to the specs in the manual from yamaha. I am puttting the finishing touches on everything now and will let everyone know how it goes. Hopefully it will go great, I am tired of not riding. Thanks to all who have helped out with the responses.

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Just an update. Everything appears to be working great. I just got done breaking in the cams. I am going to change the filter and oil and check the coolant. I also have to check the valve lash to make sure everything is still within tolerance. It runs great. I am so glad I had problems in the beginning so I had an excuse to do the work. We all know how it is with the wife and kids. hahaha lol. Thanks for all the help and talk to you soon.

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