Sitting here trying to fit new valve stem oil seals on my 748 (late model with ST4 type heads) and not having much luck. Any one know the best way? Heads are off the bike.
Cheers Mark but only fitting the seals over the top of the guides not actually fitting new guides into the heads. They should just push on surely?
Had trouble with the seals on my SS, the seals are too tight as new to get over the guides??!!! Solved by lightly stretching them over the head of an M8 allen bolt - you may need a different size bolt as your valves will be 7mm vs. 8mm, but the thought is there!
Use a tubular drift that rests on the outer steel casing. Something like a 1/4" 12mm socket or such like. Make sure they're lined up and then a sharp light tap to seat them. Grease them up to before fitting to help.
I recently changed mine on the 916. I used a 6mm bolt with a 10mm washer to pull the seal down onto the guide as hitting them on with a suitably sized socket isn't always good enough (which is why I had to change them :frown: ). Fit the bolt through the guide with the washer locating on the seal (I had to grind a small flat on one side of the washer to clear the head) and then tighten the bolt until the seal locates fully, I used some oil to lube it whilst seating. Pics should give you the idea;
praise indeed from the man in the corner. There would be a need to visually check when you get near to fully seating stem seal as apart from slight increase in effort to turn nut there wouldn't be much other indication? The ability to fully crush the seal is easily available here. My comment comes from a similar approach when fitting guides as I really hate that last half mm before it's fully seated.
