08 WR450 Valve Lash: After visit to shop

Hi Guys,

I just got my 08 wr450 back from the shop. I had the guy check the valves, and he said they all look good. The bike starts well, but I just checked the valve lash numbers that he wrote on the receipt and they are as follows:

IN#1: .005 IN#2: .0045 IN#3.0045 EX#1: .007 EX#2: .007

Doesn't that mean that the EX valves are too tight?? I'm going to call tomorrow but maybe I am missing something....

Any feedback would be great...I may already know the answer if the measurements are right...


Here is what the manual shows for valve specs...


if i was you, i would recheck them

usually they call the exhaust valves (in inchs) good if they are between "8" and 10" or (.008-.010)

IN#1: .005

IN#2: .0045

IN#3. 0045

EX#1: .007

EX#2: .007

minimum is .0079 so your below that at .007 .

they need a very slight adjustment , would think they would of told you this when it was half torn apart . not put it together and be like o we checked them they were out of spec and then put it all together , we now recommend you take it apart and re-shim them .

if you were getting them checked again in 15 hours , i would leave them (actually i would of done them when i checked the valves and found out that they were out of spec ). if you are getting them checked again in say a year - 2 years i would just do them now and get it done with .

Thanks for the feedback guys. I'll have to check them. Seems like I'm always encountering more reasons to do all the work on my bike rather than pay someone who could care less... :banana:

I just did a tech session at my Ducati service provider, the DucShop in Atlanta. This is probably apples and oranges, but the shop, which is highly regarded and runs a bunch of race bikes, sets up new Ducs with the exhaust valve clearance a wee bit tight when the bike is new. They claim that over the normal interval (6k mls.), this practice results in a closer tolerance toward the end of the cycle.

Here is where the poblem may lie: If your valves are at the min. range and you have, let's just say, a 170 shim and you go to a 165 shim then you could be at the loose or beyond the loose end of the range. From Yamaha the shims can only be purchased in increments of 5. Now when the bike is built, the factory may use a 173 shim and if you are at the bottom of the range with that then a 170 would put you right in the middle. Most would rather not here the loose ticking of thier valves. Check them yourself and if they are tight, take everything apart, verify what shims you have under the buckets without mixing up where the buckets go. If you have a shim in place that is for example a 172 or 173 then replace it with the next factory size down( ex. 170). If you have a 175 shim at the bottom of the range, mic it and file it down by .002 to .003 thus creating a 172 or 173 shim. Don't alter any shims that are odd numbers 172 or 173, they can't be replaced. If you screw up a 175 then you can buy a new one. I always shoot for the mid to just tighter than middle. Sorry for the long winded opinion. I think the tech may have been just been trying to save you some money and the annoyance of having noisy valves. I am sure if you told him to do whatever it may take to make them perfect he would have gladly taken your money for the extra labor.

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