rideblueforever Posted July 10, 2005 I have a 2002 YZ250f, original owner. Valves lasted 3 seasons, which was great. I lost compression, had to do the valves. All intakes were tight(I was told) and the exhausts were fine. Just tongiht I had to do the valve adjustment again, myself this time. All intakes were tight, couldnt get a gauge in. So my question is why did the originals last 3 seasons, and now all I got was 6 months? Is this normal? Maybe the shop didnt shim correctly? What does the intake valve clearance going out quickly indicate? Thanks Joe Share this post Link to post Share on other sites
djo269 Posted July 10, 2005 Did the shop put a warranty on their work to your bike? I would be on them in an instant cause that sounds "fishy" to me. Share this post Link to post Share on other sites
WheelsUp Posted July 10, 2005 They may not have done the work properly, but the problem could be deeper than that. Titanium valves are not particularly hard. The nitride coating is very hard. Once the nitride coating wears through, the valves will wear very quickly. I've forgotten what the "magic number" is, but I seem to recall it being around .20mm... IOTW, if your bike came with 190 shims, then by the time you get down to 170, you are very close to needing a valve job. The problem is, since you had a shop do the work (after 3 seasons), you don't know if they went from 190 to 170 or from 180 to 175. If you are capable of checking your clearance, then you have the basic skills needed to do your own adjustments... all you need is an inch-pound torque wrench, 8mm socket, and a magnet to pull the buckets off. Share this post Link to post Share on other sites