2007 Yamaha YZ250F

Check out this sweet end of season deal!

07YZ250F-1

Now with the new seat,

YZ250F-9

Notes

YZ250Fw parts list and exploded diagrams
Valve clearances:
Exhaust 0.17 – 0.22mm (0.0067 – 0.0087″)
Actuals Dec2017: L 0.203mm, R 0.178mm
Actuals Jun2018: L 0.203mm, R 0.178+mm
Actuals Dec2018: L 0.178mm, R 0.178mm
Shims: L 1.72mm, R 1.75mm
New Shims: L 1.70mm, R 1.73mm
Actuals Jan2019: L 0.203mm, R 0.178+mm

Intake 0.10 – 0.15mm (0.0039 – 0.0059″)
Actuals Dec2017: L 0.102mm, M 0.102mm, R 0.127mm
Actuals Jun2018: L 0.127mm, M 0.127mm, R 0.127mm
Actuals Dec2018: L 0.102mm, M 0.127mm, R 0.127mm
Shims: L 1.76mm, M 1.73mm, R 1.72mm
New Shims: L 1.72mm, M 1.72mm, R 1.70mm
Actuals Jan2019: L 0.152mm, M 0.127mm, R 0.152

Aug 18: 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 – got a set of bearings but there isn’t much play at all, probably install them next winter
  • New front brake lever

Completed Tasks

Feb 2019

  • Oil and filter change – AMSOIL synthetic

Jan 2019

  • Re-fill with coolant
  • Install new head gasket
  • Check piston and con rod, visually inspect crank – looks good
  • Repacked muffler

Before 2019

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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