HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
RADRick

'04 WR450 Valve Check

6 posts in this topic

After riding the track pretty hard on Saturday I decided it was time to check my valve clearances for the first time since getting my WR in November. I've got about 750 miles on the bike and have been changing the oil about every 150 miles. After break-in, I have used nothing but Royal Purple synthetic. Popped the valve cover off and couldn't believe how clean the top end was. Cam chain was tight and the cam lobes looked like new. Got out the feeler gauges and checked. All the valves were within spec. The two outboard intakes were close to the low end of spec, but not by much. The exhausts were right in the middle.

The whole process took about an hour so I decided to check my brother's '03 YZ250F, as well. He doesn't ride as hard or as much as I do, but his bike is older and has more miles. His valves were also still in spec, but a litle bit closer to the limits than mine. Just what I would have expected.

Anyone that says the 4-strokes are too complicated or require too much labor probably has a fear of wrenching on their bike. Change the oil regularly, watch the service intervals, and you should be fine. :)

Share this post


Link to post
Share on other sites

I also just checked my valve on my 05 WR 450 I agree it was simple. I checked mine at 420 miles and I checked them cold. All were in spec. I told the guy at my local shop and he said I should have checked then warm not hot but warm. Now I diddint argue with him cause thats not my thing if you know what I mean. In the manual it is not real clear but I gathered that you check em cold.

How did you do yours?

Share this post


Link to post
Share on other sites

The manual for the 1999 model (mine) and all the write ups I have read definitely say to do them cold? There is also a good discussion on them on www.thumperfaq.com and his instructions are also to do em cold so not too sure why the shop guy would have said check them while the engine is warm. My manual says run the bike then let it sit for three hours! Based on what I have felt the engine is cold. I am just going to check mine this week and will be doing the run and three hour sitting thingy.

Share this post


Link to post
Share on other sites

Yeah, all tolerances are to be checked cold. Just did mine two weeks ago after a season of racing and trail riding. All three intakes were a little tight but the exhaust were in still in the middle. Not a bad job at all.

Share this post


Link to post
Share on other sites
I also just checked my valve on my 05 WR 450 I agree it was simple. I checked mine at 420 miles and I checked them cold. All were in spec. I told the guy at my local shop and he said I should have checked then warm not hot but warm. Now I diddint argue with him cause thats not my thing if you know what I mean. In the manual it is not real clear but I gathered that you check em cold.

How did you do yours?

Cold! You need to find a new mechanic. Yamaha not only says to check them cold, but they recommend the motor not have been run for at least 12 hours before checking. I'd be real concerned about letting that shop work on my bike if they can't get this simple thing right. :)

Share this post


Link to post
Share on other sites

Rick,

I agree, I would never let that shop or any other touch my bike! The dealer that I got the bike from really tried to push me to bring my bike in for the oil changes and valve adjust. He tried to scare me with the warranty --- I said what warranty it's a dirt bike! 30 days is not much of a warranty so I am not worried about it.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0