2007 Yamaha YZ250F

Check out this sweet end of season deal!


Now with the new seat,



YZ250Fw parts list and exploded diagrams
Valve clearances:
Intake spec 0.10 – 0.15mm (0.0039 – 0.0059″)
Exhaust spec 0.17 – 0.22mm (0.0067 – 0.0087″)
Intake: L 0.102mm, M 0.102mm, R 0.127mm
Exhaust: L 0.203mm, R 0.178mm
Jun2018 (3-4 hours)
Intake: L 0.127mm, M 0.127mm, R 0.127mm
Exhaust: L 0.203mm, R 0.178+mm
24 Aug 2018
Backed off pilot air screw ~1/4 turn to address hanging idle and tough warm starts (although we weren’t following the procedure in the manual)

To Do List

  • Replace upper rear shock bearing
  • Replace kick start lever or do better fix
  • New front brake lever

Completed Tasks

  • New front brake reservoir screws – thanks TSR
  • Set race sag and suspension settings to stock
  • New tires – Bridgestone Battlecross, needed a new inner tube as well since someone had used a bicycle tube and a load of tape!!?!
  • New front brake pads – EBC sintered
  • Install new grips
  • Seat has been cut down, new seat
  • Replace fork seals – used Motul Factory Line 2.5wt fork oil on recommendation from JWR Suspension
  • Oil change
  • Very small amount of play in front wheel bearings, replace
  • Check valve clearances –
    Dec 2017
    Intake L 0.102mm, M 0.102mm, R 0.127mm
    Exhaust L 0.203mm, R 0.178mm
  • Check for any play in main bearings – none at all, sweet!!
  • Move kick start away from frame


3 thoughts on “2007 Yamaha YZ250F

  1. MTOAdmin Post author

    Before removing the forks to change the fork seals, it is best to loosen the cap on top. On these forks that requires a special tool, a large octagonal wrench. These can be bought for about $30 but I was convinced that I could design a tool that could be 3D printed. After a couple of iterations and several hours of printing, the tool in the pic worked a treat! Both caps are now loose and the forks are ready to be removed.

  2. MTOAuth

    First time out at the track I had the lad ride the 4 stroke as I figured the smooth power delivery would be easier for him to cope with. He did excellent, only had one little fall in a corner and was soon hitting some decent jumps. When he tried the 125 SX on the next outing, he came back with a huge smile on his face and said “I want to ride this, we’re trading”! I rode the 125 SX exclusively on the first outing, and loved it, I wasn’t overly keen on even trying the 4 stroke but after a couple of laps on it I was sold! The YZ250F handles great and gives confidence over the jumps with the smooth power, vastly superior to the old 2001 YZ250F I had. There is a harsh double on one section that I daren’t attempt on the SX but after a couple of laps on the YZ, I went for it and cleared it no problem! The only bit of concern now is the reliability, the experience with the 2001 dropping a valve has shaken my confidence. It sounds a bit rattly to me especially when you shut off the throttle but I’m not sure what is ‘normal’ for these.

  3. MTOAuth

    Out at the track again yesterday, bike ran great! Only minor thing was that the gear shift lever worked loose – same on the KX100 weirdly?? Oh also the front end washed out a couple of times but I think that was rider error.
    I was nailing some of the jumps and doubles but still jibbing out on the big ones. The old RXR inflatable body armour I picked up was nice and comfy, not too bulky.

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