deciding

Go for the blue. You can buy new gear with the money you would have spent on the honda when it drops a valve.

Go for the blue. You can buy new gear with the money you would have spent on the honda when it drops a valve.

Ha thats a good one, I dont think the honda 450's have as bad of valves as their 250s.

Ha thats a good one, I dont think the honda 450's have as bad of valves as their 250s.

its probably seems they last longer cause its a lower rpm engine, that people more likely would lug

its probably seems they last longer cause its a lower rpm engine, that people more likely would lug

no but seriously does anyone have physical proof that honda's have worse valves than Yamahas, and not by experience, If its true, Why are the honda valves not so good?

no but seriously does anyone have physical proof that honda's have worse valves than Yamahas, and not by experience, If its true, Why are the honda valves not so good?

well, I don't have proof, but I asked a Honda Rep and he said they do fail prematurely.

his rationale was that dirt gets past the filter, goes into the engine, and the valve beats it into the seat, then when the valve spins it gets sanded down by the dirt.

I asked a engine builder, and he said the stock valve springs wear out really fast and make the valves bounce against the seats

go over to the yamaha section, and ask people how long there valves last, then go over to the CRF forum and ask them how long there 1st set, this is important cause people can cure the bad valve problems, of valves lasted them.

my valves lasted well over 300 hours without being touched and being in spec. my bike took me 3500 miles on its stock valves

so HONDA is well aware they had a problem

I had a 2004 crf450r and the valves did need more attention than my 07 wr450. Whenever I checked the valves on the crf they needed adjustment. Whenever the wr has been cracked open, the valves have been spot on. The crf never needed new valves, because I stayed on top of the maintenance and never let them get too bad. However if I hadn't been it would have meant a whole new top end. The honda was a very nice bike though, very fast and responsive. The crf450x is on par with the wr until 07, but when the wr's went aluminum they pulled ahead by quite a bit.

I had a 2004 crf450r and the valves did need more attention than my 07 wr450. Whenever I checked the valves on the crf they needed adjustment. Whenever the wr has been cracked open, the valves have been spot on. The crf never needed new valves, because I stayed on top of the maintenance and never let them get too bad. However if I hadn't been it would have meant a whole new top end. The honda was a very nice bike though, very fast and responsive. The crf450x is on par with the wr until 07, but when the wr's went aluminum they pulled ahead by quite a bit.

if you shim more than 3 times, the valve can fail. see, the valve and seat both wear, so when you shim, your making the gap larger so the bike can run like it was designed to when its hot.

your actually supposed to remove the valve, and measure the thickness of it, and when it gets out of that thickness, you are in trouble and need to replace that valve

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