valve adjustment By larry (Read 5,675 times)

[larry]

I have a 250cc 2008 scooter made by JM Star. The head on the engine tilts to the rear and the valves are on the lower front like on a 50cc. Would anyone know the valve adjustment on that engine. What's the best way to tell the intake from the exaust valve. On the side of the scooter it says MC 13 250.

[Cruiser]

I would guess you have the 244cc Honda clone engine. The valve adjusters are just above the sparkplug. Here's a video showing the valve adjustment procedure. The adjusters are marked - exhaust is the right one and intake is the left one. This example is a dune buggy and there is usually an access door in the bottom of the seat bucket on scoots.

[kalee]

I'm getting confused, I have been told you adjust the valves on a YY250T with the engine cold and i have been looking at a video on this website that show's adjusting the valves on a CN 250 after the engine has been warmed up. Which one is right?

[Alleyoop]

On yours you adjust them while the motor is running. The adjustments are on the outside you do not have to take anything off just loosen the screw and adjust one at a time.
Alleyoop

[richardthescooter2]

That part of the adjusting would be nice.

[richardthescooter2]

If you have the 244 engine, that would be right.

[richardthescooter2]

here is the 244 engine.

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[richardthescooter2]

Here is the 257cc engine, which one is yours? (You adjust this one cold)

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[Alleyoop]

Mar 19, 2013 11:35:38 GMT -6 kalee said:

I guess i want to make sure i'm on the right track before i start adjusting the valves on my YY250T engine ( its a 2011 ). The video I was watching is highlited on this page and it looks like the motor is on a 4 wheel dirt buggy of some sort. Is this the proper way to adjust the valves on a YY250T engine with 266 miles on it ?

The buggies and atvs have the same motors as the SCOOTS the only difference with those some have more wheels. If you can fix one you can fix any of them.
Alleyoop

[kz1000st]

Now the bike seems like when i start to go for a ride it has a vibration when it first starts to take off, it will come out of it when it gets more rpm's.Would this have anything to do with the valve setting? Runs great once i get the rpms up

I'm not saying you have the same problem, but read this.

scooterdoc.proboards.com/index.cgi?board=250cc&action=display&thread=6946

If I had known what the problem was and might fix it I would have taken off the variator cover and checked the nuts on the clutch and variator. I suspect that the nut on my CN 250 engine was loose and caused the bell housing on the clutch to rattle around and break the shaft.

[Alleyoop]

Kalee,
That sounds more like your clutch pads are glazed and are slipping at very low rpms. Don't forget they work with centrifugal force the more force the harder they stick to the bell which turns the shaft that turns your wheel. That is why at a little higher rpms the pads then have enough centrifugal force to grab the bell good with no slipping.
Alleyoop

[Alleyoop]

There are many Videos here is one on how to take the Nut off to get the clutch off. Once you do that you can then clean it out get some sandpaper and take the glaze off the pads and grease the Pad swivel points.
Alleyoop

[rapidjim]

No way would I attempt the second one. For one, my knees are not what they use to be. For two, my luck I would slip off, clutch and spring would expand upward at an alarming rate and I would be speaking with a very high voice.


Jim