new problem spuders and won't stay running By seanstr (Read 6,154 times)

[seanstr]

Ok, it's still doing the entire problem. I have a new cdi, I'll install tomorrow

[seanstr]

It dies, then hard cranking, won't start then it gets past that, & starts, then runs badly, then I open it up all the way, it runs fine again. Need help

[seanstr]

& mis-fires

[Bashan]

Does it run poorly up until you get past about 1/3 throttle? Take off from a start and slowly increase the throttle. See if you can tell what point it starts running OK. I think I might know what's wrong. Rich

[seanstr]

Ok, this is what happens. I normally start off fine get to where I am going. Then I need to go somewhere afterwards, it starts, but isn't running right. I try to go, it stalls. I start again. Same thing. It will idle. I try to go slowly, it'll go but it's super slow, sputters the entire time, chokes back fires all the time. If I get it to smooth out, by some miracle, it will then run fine, it returns unless I drive the crap out of it, wto. It is infrequent. When happens though it can barely do 20mph. If isn't doing this I can get it up past 58mph. Everything I've read says it's the cdi. I'm trying to get a new one tomorrow, sorry wednesday. I'm driving there to get part. Trying it out there. Making sure it runs

[seanstr]

Also, if it smooths out it isn't as I'm getting past 1/3 throttle. I mean as I'm idling. It'll just magically get better

[seanstr]

Just rode last night home, backfires but ran ok. Morning, rode to ymca again, same backfires on dec, but runs fine. I'll explain more when it does it again.

[seanstr]

Ok so I rode to y, no problem, left went to work, didn't turn off, then went to walmart, shut off. Went to leave started acting up again. Same issue. If I can get it to smooth out magically, it goes

[sprocket]

Check the two wires on the ignition coil.
Check the big black wire going from the ignition coil to the plug boot. Check that the plug boot grips the spark plug firmly...

It sounds to me like it could be an intermittent electrical connection somewhere

[seanstr]

The rest of the post has the plug wire replaced already

[Bashan]

You did put a new coil on with that plug wire didn't you? I thought you already got a new CDI. Popping and mis-firing on decelleration can mean a bad cut off valve on the right side of the carburetor. I'd take that off and inspect the diaphragm just to make sure it's not cracked. Also check the vac line running to it. Rich

[seanstr]

No cdi was wrong, it didn't work when I hooked it up. Wouldn't start nothing, sent it back. Refund coming. It only does it sometimes, why the diaphram? Also something else I noticed. If I keep it from backfiring at all it doesn't do it. If I go somewhere then stop turn it off, then not long after go again it does it. I hope that helps

[sprocket]

Have you got an exhaust system on the scooter now?

Backfiring is air getting into the exhaust header, or you are running lean or the ACV is not function as Big B mentioned.

[seanstr]

What is ACV?

[Alleyoop]

First thing to check is what Sprocket mentioned the EXHAUST Flange connected to the motor. Sometimes a Nut comes off and or loosen up and blows out part of the gasket. That will backfireing.

In either case the reason it backfires it is running LEAN when that happens.
The ACV(de-excelerator) only comes in to play when you let go of the throttle to feed a shot of fuel into the intake so it does not Backfire when all of a sudden you cut off the air and fuel.
Alleyoop