HELP!!!! Roketa MC-54-250B Running Crappy By insanetexan (Read 659 times)

[insanetexan]

To start off wanna Hi to every one after being absent for quite awhile.

I am still having a problem with my scooter. I had it running good for a while and then it just bogged out and won't run for crap.
I have adjusted the valves as per JR's settings of .004 at the Intake and .005 at the Exhaust. I have also cleaned the carb since it has been sitting for awhile just to make sure it is in good shape. It has fully charged battery and I tried adjusting the A/F screw and there was no change in how it ran. Also attached a vacuum gauge to the intake and took that reading at 10 in. HG i think is the correct way to say it. Not sure what the vacuum should be but according to the gauge it is showing to be a leak at the intake manifold or not advancing the timing.

Could the CDI be bad since the timing may not be advancing? I have not seen of any way to adjust the timing on these things.

Any help would be greatly appreciated since I haven't been able to ride my Scoot for over a year now and would really like to get back on the road.


Hope this link works to the vid of it running; tinyurl.com/hsstylj

[cyborg]

It's a air leak ,,,

[insanetexan]

I'll give it a shot and see if I can find one and fix it.

[insanetexan]

Well I looked for a leaked and didn't find any. But I did recheck the valve settings and reset those again. I then changed the diaphrams out in the carb with some others I had here from an old carb and got it to finally idle a little smoother. Even though it would idle smoother it would still bog out when the throttle was twisted.

I am stuck now in a spot to where I am gonna have to either buy a new carb or a new choke for it. I accidently broke the choke on the carb.

[cyborg]

See if you can just get the choke ( enricher)

[richardthescooter3]

Check your intake manifold, I had a leak in my roketa scooter right under where the clamp tightens

[ellpee]

You can indeed buy the enricher separately, think I paid $20 or so, and until you replace that it's not going to start well no matter what else you do. On the other hand, a whole new carb is only about $75 and will eliminate a lot of other possibilities in one swell foop. While you're waiting for the carb you can remove both manifolds, in and out, and check them as thoroughly as possible for any leaks, cracks, pinholes.

[insanetexan]

I went ahead and just ordered another carb off ebay for 43 bux. Gotta wait for that to come in probably next week sometime, it's only coming from California to Texas, but sometimes that can be like coming from China on the wait time.

[insanetexan]

Got the new carb in and installed and also changed out my fuel filters. It will start right up and rough idle but still bogs out on the twist of the throttle. I am puzzled, cause when it first happened I was riding it and it was great. But came to a red light and when the light changed I twisted to go and that's when it bogged out and died. Been that way ever since.

The question still stands that could the CDI be at fault?

Looking for a leak in the intake I sprayed starter fluid around it all over and nothing changed as far gaining any motor rev.

[ellpee]

Since the throttle has little or nothing to do with the ignition electrical, just tells the carb to let more fuel through to the cylinder, my gut instinct says no, still something in the FUEL system. Adding throttle should give an extra shot of fuel, richer mixture briefly, more accel, and as rpm increases timing should adjust accordingly. But I'm by no means a guru, so if anyone else here chimes in with ideas, listen to them first.

[insanetexan]

Ellpee that is why I am wondering about the CDI cause as I am to understand the CDI is suppose to advance the timing some how. I by no means am not sure how that works. Only reason I am under the impression the CDI advances the timing is because of the CDI set-up that Kid-N-Me sells that is adjustable for advancing and retarding the timing. I am by no means an electrical expert but I am a shade tree mechanic. Have worked on a lot of vehicles in years past. I would hate to purchase the CDI that K-N-M sells for 125$ and that still not work out my problem, that is the only reason I am trying to find out about the CDI.
Only other thing I can maybe think of is the timing jumped a tooth or two. When I tried to set the timing marks to adjust the valves I did notice that they were out of sync. When on TDC and the mark on the stator side was lined up the mark on the cam gear was off by a couple teeth in lining up.

Hell I am lost.

[richardthescooter3]

When you got your new carb, did you take to top of carb off and check the diaphragm to make sure its sealed and down tight, that happened to me, bogging down, that is where my problem was,