Going to check my valve lash on my day off, tomorrow...but decided to do the tear down as soon as I got home this evening....on a
hot engine. (sort of-- it is 33degrees F out there )
Just for the heck of it I checked the valve gap on the hot engine.
Tomorrow I will check it again when the engine is cold (@30 degrees F). The valves are to be checked only on a cold engine. (over night is best) So, if you take your scooter in to the dealer for service and a valve adjustment is part of the order - they should not give it back to you in an hour or two!
For those who'd like a refresher...or have yet to check your valves, I took some pictures:
Remove seat bucket (w/seat attached to it!)
Remove battery cover and cover with heavy cloth.
Remove center cover to expose valve cover.
(Disconnect spark plug cap, for safety.)
Remove plug on fan cover to expose timing mark ("T" and a line, nearby)
Remove rubber vacuum line from valve cover.
Remove four 10mm bolts on valve cover (if you forget where they went - match bolt length to casting depth on the valve cover)
Rotate engine clock-wise with a 14mm socket on white nylon fan nut (look in there, you'll see it...I do
not remove the spark plug to make it easier to turn engine over: engine is not that powerful and I don't like re-threading that little plug too many times, to avoid cross-threading it)
Align "T" with the notch and align two hash lines on chain sprocket with edge of engine ...if correct you can grab the adjustment nuts and feel slight movement when you pull/push them. If NO movement...rotate engine 360 again and try again. Do not adjust anything if you do not feel a bit of movement in each valve adjusting nut because you have not found top-dead-center, necessary to adjust the valve lash.
When I checked the valves on this hot engine I got .oo5 on the intake and .oo4 on the exhaust valve. The correct setting is .oo4 inches - or 0.10 mmInsert feeler gauge blade. Loosen the lock nut then turn center screw to get proper light drag on the blade. Snug lock nut, if still good - do the other valve. Rotate engine to TDC and check them both again.
I reuse the valve cover gasket if it looks good and add a small bit of heavier gear oil to the moving parts before replacing the cover. Tighten bolts gently in a X pattern...do not overtighten these alloy parts. Just snug.
Replace vacuum rubber hose onto valve cover.
Start the engine after replacing plug cap. Check for leaks around the valve cover...if good- - button it up. (replace center cover, battery cover and seat bucket)
I use 4 feeler blades: .oo4" ,+ and - , and use them to check my valves. If the .oo5 fits....I keep adjusting until only the .oo4 fits, etc.
Stig
