I bought a '03 XT225 with seized cam bearing. It had the oil filter shown below installed and clean oil in the crankcase. The oil flow to the head was blocked by the rubber end cap and lack of holes in the incorrect type oil filter that was used. Be sure your oil filter has the holes shown below.

Yep, unfortunately that's not an unusual problem. Yamaha was exceedingly stupid in making the 225 and 250 oil filters physically interchangeable but not functionally interchangeable. A lot of shops seem to have forgotten the 225 exists and will give everyone a 250 filter.

This is the purpose of the "bleed bolt" on the 225's head near the spark plug. After an oil change, loosen this bolt, start the engine, and confirm oil comes out before riding. It can be messy, but a cleaning up a little oil is better than rebuilding the head.

Also note that these filters are easily cleaned and re-installed. Replacing it every time isn't required.

Not one of Yamaha's better design moments. I too clean my pleated screen filter with a tooth brush. Usually in diesel fuel followed by blowing it dry with compressed air. It can be recycled many times like this. Make sure to inspect the rubber gasket carefully. And look for pleats broken at their folds. One pleat overlaps on the cylinder so don't mistake this for a break.

DON"T LOSE the small O-ring on the cover's feed bolt. Your lower photo shows that O-ring at 5 O'Clock.

As for the drain plug, its threads are exceedingly delicate. Caution advised when reinstalling it against the spring pressure of the mesh filter inside. Ride safely and enjoy!

Not one of Yamaha's better design moments. I too clean my pleated screen filter with a tooth brush. Usually in diesel fuel followed by blowing it dry with compressed air. It can be recycled many times like this. Make sure to inspect the rubber gasket carefully. And look for pleats broken at their folds. One pleat overlaps on the cylinder so don't mistake this for a break.

DON"T LOSE the small O-ring on the cover's feed bolt. Your lower photo shows that O-ring at 5 O'Clock.

As for the drain plug, its threads are exceedingly delicate. Caution advised when reinstalling it against the spring pressure of the mesh filter inside.

There are some videos on XT225 oil changing and grease in the Learning Center. Doesn't cover the head bleed bolt, however. Ride safely and enjoy!

My drilled bleed bolt makes for less mess, I posted a pic of it some time ago, dunno where it is now.

If you used photobucket, it's likely gone when they shafted everyone.

Pure evil what photobucket did. That destroyed decades of DIY automotive know-how.

I bought the XT225 seized so I got it cheap. The PO got it same condition from a guy (PPO) who was selling a pair, one seized and one running. I warned the PO who still has the running bike to check his filter immediately because they were likely bought together and oil changed together. Haven't heard back about it.

I found the original pic of my bleed bolt mod, see pic. I drilled through the centre then drilled in to meet that approx 3mm in from the head. This makes it easier to bleed, just unscrew a couple of turns & it's everywhere. Ha.