back fire and miss By scooterbob (Read 483 times)

[scooterbob]

I wrote a long message about a problem with my scooter. Hit post and never showed. I'll make it short. My scooter started backfiring and missing on acceleration. I have another CDI I will try that first. Then check the plug color. It has been running great started great. Now it turns over a lot before it starts but idles fine. Any help is appreciated. Thanks.

[Alleyoop]

First thing check for AIR LEAKS or a cracked hose allowing extra air to be sucked in, or your air filter came loose etc..

If it still backfiring check the FLANGE on your exhaust pipe that is the PART that bolts up to the motor. Sometimes if the muffler comes loose or is loose it will vibrate the whole thing and it may even cause a nut to come complety off and will leak really bad.
Alleyoop

[scooterbob]

I left out one very important point. It backfires on acceleration not deceleration. Sorry about that

[Alleyoop]

Since you mentioned it is missing as well check the wires going to your coil, they may be loose or touching that would cause the backfire and missing as well.
Alleyoop

[scooterbob]

I spent the checking ignition connection, spark plug color, adjusting the valve. All was connected, spark plug tan and valve gap exact. I replaced the CDI that came with the big bore kit with the blue fin marked for racing. So far so good. I will add that yesterday the temp. was 95 f. may have contributed to CDI failure . That is if it was the CDI. Need to take a long ride tomorrow to be sure. It's nice to be retired and do what you want when you want. Scooterbob Round pants. Thanks for your help alleyoop.

[Alleyoop]

Well good luck and hope it was the CDI and or the HEAT WAVE.
it got up to 98F here today, hot man was it hot. They say a cool front is coming in Thursday or Friday I will believe it when I see it(HAHA).
Alleyoop

[scooterbob]

The cool front came in today only 83. Might have to wear a windbreaker this week. Later Bob