Backfiring clone
- Thread starter larmer
- Start date
- Tags backfiring clone
first i want to thank the form for the inspiration to assemble a doodle beast, only drove a block and super asome sauce!
well as for the back fire, it occurs on deceleration after at a high rpm, and after a wide open throttle, a flame pops out of the exhaust when the bike is supported on a block. i checked over the float bowl before starting the engine for the first time, (as recommended on a post of this forum), thank you all for the info, i will read more into my problem with backfire, and dink with my db, then report back.
the exhaust is stock, i will run the bike and take a plug reading,
a question, how harmful is backfiring on my clone engine?
well as for the back fire, it occurs on deceleration after at a high rpm, and after a wide open throttle, a flame pops out of the exhaust when the bike is supported on a block. i checked over the float bowl before starting the engine for the first time, (as recommended on a post of this forum), thank you all for the info, i will read more into my problem with backfire, and dink with my db, then report back.
the exhaust is stock, i will run the bike and take a plug reading,
a question, how harmful is backfiring on my clone engine?
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I rode the bike at a high rpm for about ten minutes, and then checked the spark plug. It is pretty clean and white, which I guess means it is running lean.
Is there any way I can adjust this without changing the jets? I mean, if I have to change the jets I will, I was just looking for a solution other than that, if possible. Thanks!
Is there any way I can adjust this without changing the jets? I mean, if I have to change the jets I will, I was just looking for a solution other than that, if possible. Thanks!
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still backfirin n running real lean@!
well, i clogged the tiny pin hole on exhaust(was not the prolb)
i disassembled the carb, checked over jet, and holes, everything really clean and looks fine.
the engine pops after deceleration of full throttle.
there are no jet adjustment screws, only a small screw to let air in for the low idle.
eaggg i just don't know what to do now?
at full throttle the rmps fluctuate, i back it off just a bit and it runs smooth, (besides all that the bike runs very well). ..
well, i clogged the tiny pin hole on exhaust(was not the prolb)
i disassembled the carb, checked over jet, and holes, everything really clean and looks fine.
the engine pops after deceleration of full throttle.
there are no jet adjustment screws, only a small screw to let air in for the low idle.
eaggg i just don't know what to do now?
at full throttle the rmps fluctuate, i back it off just a bit and it runs smooth, (besides all that the bike runs very well). ..
Generally Stock out of the box Clones will run lean. they are setup for random inspection and Smog testing. Running lean helps them pass the EPA/CARB tests Hydrocarbons and CO2 they do not test for NOX on small engines which is what is produced in lean conditions.
Up jet 1 or 2 jet sizes it will go away. Also pulling the choke a little should help you out.
Up jet 1 or 2 jet sizes it will go away. Also pulling the choke a little should help you out.
The backfiring isn't necessarily a bad thing. Not sure why you are so worried about it. As long as it runs fine up until the governor hits (which sounds like what the surging is you talked about) everything is normal. I've had clones backfire out of the box on decel and others that don't.
Valve adjustments and the jet size will make a difference but if everything else is good i'd just leave it alone... sounds neat.
Valve adjustments and the jet size will make a difference but if everything else is good i'd just leave it alone... sounds neat.