Don't flame me, when do i NEED to check valves

03 crf450, not cranked in a week, twisted throttle 2 quick times and cranked on second kick. last weekend, ran it thorugh ocala national forest down the fast whoops for 30 minutes straight, stopped to catch my breath for 5 minutes, kicked one time and off i go again. matter of fact, only time it did not start in first 3-4 kicks was when the spark plug died a few months ago, installed new plug and cranked first kick. i just want to be pro-active, so do i need to check valves or wait until it backfires or is hard to start

by the way i only turn the throttle when not cranked up in a few days or when its cold down hear (50 degrees this am)


You can check the valves when ever you want. But I wouldnt bother unless it gets impossible to kick start, but will run when bump started.

By the way, backfirers arent symptom of bad valves.

Your 450 has much better valve life than the 250's do, the little bikes have the bad reputation. That being said, it's not a bad idea to check your valves every now and then. It's so easy to check them, and repairs can be very expensive if they fail. Yeah, you have the typical warning signs like hard starting, but you can damage the seats and coating on the valve face if they're run out of spec for a while.

You changed your spark plug a few months ago, you're about half way there to doing a valve check. Taking the gas tank off is the longest part of the whole job.

Don't worry about checking them real often. Just deal with them once it becomes hard to start. If you race or can't tollerate the down time when they do go then just go buy a spare head and put the valves and springs in it so its ready to go. The 450 head is way cheaper :naughty: than just about any other 4stroke on the market so it doesn't cost a fortune to get a spare and keep it on hand.

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