250cc 2008 JCL keeps stalling & won't start

[ScootrGirl]

PLEASE HELP. I'm desperate. I bought my 250cc JCL scooter in 2008 brand new and had a blast with it for about a year, putting about 7500 miles on it in that 1st year. Then I bought a Harley Sportster 883 and put my scooter away for awhile. After a broken ankle I decided to sell the Harley and start riding my scooter again. I bought a new battery to get it started and rode it to my service man for a complete tune up, oil change, etc. to get it road ready. When I would come to a stop, I would have to keep my hand on th throttle to keep it from stalling out. Now, after several months of him working on it, it is still the same. I even have a new guy checking it out, n he is also having problems getting it started and keeping it running. After several tries, he can get it started and it runs fine while on th middle kickstand but stalls and won't start again when he takes it off the middle kickstand (one of the same problems the first mechanic had). If either of them gets it started on the side kickstand and then gives it a shake from side to side, it will stall out again. Also, i never had to touch the throttle to get started when it was new, and now both mechanics say I have to give it some gas to get it to start. So far, I've had a new carb, new stador, new brakes and brake assembly, new fuel filter and another new battery put on by first mechanic. Now the second mechnic has put another new carb on it, replaced the CDI and a 3rd new battery, and now says he has ordered another new stador (assuming the 1st mechanic must hav gotten a bad carburetor, bad battery, bad stador, etc.. I've already paid out about $600 with the 1st mechanic with no results and I don't have another $600 to give the new guy to replace all the new parts. Please, please, please someone help me to help the mechanic by telling me what actually might really be wrong with the scooter.

[bandito2]

Hope the guys haven't been scamming and taking advantage of you.

Seems obvious for a loose, poor(contaminated with corrosion possibly) or broken connection if it is quitting when you shake the bike. On the center stand /side stand issue may indicate that too by a connection failing/disconnecting because the bike is tilted. It could be an electrical grounding issue.

It sounds like a wiring issue. Have ALL of the engine starting, running connections cleaned and wires checked. Once it ever does get started, the idle may need adjusting so you won't need to keep giving throttle on start & idle.

There also might be a problem with the fuel delivery. Failing pump or poorly connected fuel pump wiring, plugged fuel filter or possibly kinked fuel lines. Fuses should be checked as well. I might have thought part of the problem may be trouble with the carb float, but since the problem persists after carburetor replacement, that wouldn't seem to be the cause.

Not sure how your scooter works, but on mine, the bike will not start or run if the side stand is deployed down, (a safety feature) but it will if just using the center stand. If yours is actually like mine in that respect, there might be a problem with the side stand switch.

HTH

[ScootrGirl]

Thank you bandito2. I will ask them to check all the wiring before they put another new stador on.

[kz1000st]

OMG! Has anybody adjusted the valves. What you're describing is a classic case of tight valve clearance. The exhaust valve gets hung open and you lose compression when the engine gets warm. Ultimately it holds the valve open so much it won't run anymore. Have your mechanic check that. Instructions for adjusting the valves on a Linhai 257cc are on Youtube.

[ScootrGirl]

Thanks kz1000st. I have suggested this from other posts. I asked him to check n c if intake was set at .004 and exhaust at .006 (intake on top and exhaust on bottom). Is that right?

[bhinch]

Hi..once the valves are adjusted....the idle can be set. Just getting the valves adjusted will cure many problems... I have over 11,000 miles on my scoot and the valves have been adjusted once. Like you said .004 intake and .006 exhaust.

[bnc]

If it is the JCL MP250A, adjusting the valves is not trivial.

https://www.youtube.com/watch?v=i4PAshnNCoE

It looks just like a Honda Reflex but with the Reflex it just takes removing a little door on the left side to do the whole job.

[kz1000st]

Thanks kz1000st. I have suggested this from other posts. I asked him to check n c if intake was set at .004 and exhaust at .006 (intake on top and exhaust on bottom). Is that right?

Yes. That's correct. Once the valve clearances are set you should be good to go.

[ScootrGirl]

Than to all who replied. My scooter is finally running again and it only cost me 500+ this time. The latest mechanic was at a standstill until I sent him various posts from this site and within a couple of days he called and said I could come pick it up. The one thing I noticed added to the invoice besides the 2nd new carburetor and 2nd new stador which hadn't been mentioned until after sending him the info I found on Scootdawg was a regulator. He also said they checked all the wiring and set the valves as instructed on here, so after paying out approximately $1500 between two mechanics and two brand new carburetors and stadors (one for each mechanic), I'm finally on the road again. Next time, I'll check here first to c if I can do the work myself.

[kz1000st]

It's too bad it cost so much. It would be nice to know what the problem really was. All these "Mechanics" act like the carburetor is always the culprit and change it since they're comparatively cheap. Most times it's something else, like the valve clearances, and they just shoot in the dark until they hit something but you have to pay for it. I hope you get many good miles out of the scoot, you certainly paid enough.

[bhinch]

Glad you got her fixed....enjoy....don't hesitate to ask for help on this site...great folks and lots of answers...