cylinder head spark plug hole oil seal

Hi all had a small leak of oil for the past year on the left hand head, so yesterday decided to do a service on the bike ready for the year, valve clearances, oil filter, oil etc, now as i was putting the cylinder cover back on it wouldnt go flush and sit there so pushed the four bolts in and proceeded to tighten the cover, (right hand side popped straight on) so then removed the cover to find that the oil seal in the centre had not seated properly and yep i created a small tear and caused the leak, sorted now as put the new seal on and put a bit of oil on the outside of it and the cover popped straight on. lesson learnt.

As a short term fix, you can rotate the seal so the tear is at the top and this will reduce the opportunity for oil to escape.

There may be a little problem in the head.
A washer is on the way when you install your valve cover.
Grind the excess away. It helps to install the valve cover with the oil seal.

Look here, klik

And here, klik

You fit the seal onto the rocker cover before fitting. They usually stay in the head when removing the valve cover. Pick the seal out and fit onto cover before replacing .