got a deal on a 05 yz250f. Rode it for day and realized it didn't cold start the easiest. Went to check valve clearances and exhaust were in spec but intake were all too tight. I put the smallest shim in and still way off the tightest spec. The original owner installed new crank, n cylinder kit and I'm guessing it's still the original valves in the new cylinder. Do I just buy new oem valves? Your info greatly appreciated.
Yz250f tight intake valves
- Thread starter NickyV250f
- Start date
Since the cylinder and head are brand new, would just installing new valves fix my problem. I'm on the smallest shim n buckets are still too tight.
Get the Yamaha service manual 1st. That's service not owners manual. If you already have one then you are already ahead of the game. 2nd if you can not shim the valve anymore than it already is then you need a valve job which at bare minimum is replacing the valves. The head will need to be looked at for damage. Find a reputable shop that sells parts and does repairs. Buy some parts get your head measured up for free is usually the rule of thumb for the really good guys.
This is what it could look like if you continue to ride or cheap out on doing the right job.
Alright I'll pull the head and see what's going on. Crazy that this has brand new cylinder and within a few hours the intakes are zero'd. Anything I should look for to see if any more damage was done due to valves tightening up?
I would like to see a picture of the bottom end from that head Mikey.
I'm sure you can imagine the carnage.
I'm anxious to see if it even had a new bottom end.
Your service manual will tell you what to look for.
It's not, I meant the cylinder is