So who has adjusted their valves??? When should this be done?

[htcneil2]

I'm at +34,000 miles and have yet to it. Could this be the cause of MPG drop?

[ce]

Yeah, it's easy, you just have to push down on the frame for the valve cover to come off. Some people jack up the wheel, you'll see when you go to open it up.

.004 inch intake .004 inch exhaust

You may be losing some compression due to the exhaust valve closing up, the intake doesn't change much usually.

The best thing about doing it is then you know how, and it's no big deal.

[htcneil2]

you have an xciting?

[drifter]

afaik the manual says every 10,000kms.

[Hoolander2]

You'll have to take off the seat, the underseat storage bucket, floorboard, skirts, accent trim pieces first.  Yeah, what ce was saying about pushing on frame means have a partner sit on or push down on back of the scooter in order to get valve cover up and out.  OR as I have done, wind a cinch strap through rear wheel and around frame and cinch down.  The idea is you have to change the angle of the engine before valve cover will come up and out.  You could also cinch the rear of the scooter to stationary tie-down points such as on a bike lift which I think would be easiest of all.

Remove one nut holding thermostat so you can push it up out of the way when valve cover is coming up.  Also remove coil and place forward out of the way.  Neither has to be disconnected -- just pull spark plug wire off spark plug. Valve cover will want to hang up on cam chain on the way out -- just be patient and gentle and watch the gasket.

YOu'll need a nice LITTLE 9mm wrench.  I had to grind one down to get in there.  Then something to turn the adjusters (kymco makes a tool for that) I made one out of ball point pen parts. And of course feelers.

I broke a valve cover bolt by overzealously tightening.  They're thin and can break easily so just tighten them good and snug. 

First time I did it it took hours and a whole lot of grunting.  Not to mention putting the job on hold while I found a wrench and ground it down to fit the lock nuts.  I'd do it again now when it needs it but I won't say it's a piece of cake.  Seeing in and getting the feelers, wrench, and adjuster in place is quite a pain if you ask me.

[ce]

Thanks for the clarification Hoolander, that was good.

I had a lot of practice on GY6s and the Linhai 257, which has 2 valve covers, so it was nice to work on the Kymco, which is an awesome machine.

I have a 500 and a 250 Xciting, and the 250 is much easier in that there's plenty of room to work, and the frame's not in the way.

The owner's manual list adjustment intervals at 300, 3000 7000 and 11000 kilometers, but I only opened up the 500 when it started acting up, stalling, low power, hard starting, and sure enough the exhaust valve was about closed completely.

You do need to review the tech manual, but basically you remove the right side cover and the spark plug, then turn the crank with a wrench until the marks line up in the sighting hole and you should be at top dead center.

It's not for the novice, but the design is really good. There are no surprises if you follow procedure. Otherwise you gotta pay someone $80 an hour and hope they read the manual.

If you can do it, you're a damn good Kymco mechanic, and when the scooter runs great, it's a damn good feeling.

[slugrocket rob]

Wow, 34,000 miles without a valve adjustment! It is deffinetly over due! As you need to remove much tupper wear, it is a good way to get to know your scooter!