Occasional popping in carb?

MICRider · 11-01-2009, 10:58 PM

Hello, was out putting around with my son tonight for a bit. My Beast runs much better with the new Mik on it (though I still haven't had a chance to tweak it), but I still get the occasional pop/hesitation on it. It will stall the machine if it catches it just right. Funny part is that the pop seems to be coming from the carb... Is it possible that the valve lash is a little tight and it is backfiring through the carb? Or would it more likely be a timing issue? Lol, though I would have to refresh my self on setting timing (can you even set the timing on these 200cc engines?). Or... Is it just cause I don't have the carb set up right? I should probably tweak it some more and see if that cures it, does run 100 times better than it did with the stocker still.

Anyone else had the popping issue? Surely does sound like a backfire through the carb throat.

Regards,
Stew

MICRider · 11-01-2009, 10:59 PM

Lol, I am jealous of the 110... Purrs like a kitten and never misses a beat!

Weldangrind · 11-01-2009, 11:28 PM

Maybe it's just a little lean Stew. I'd be inclined to adjust the air / fuel screw first, because it's easier. Besides, the air / fuel screw is resposible for idle and the transition from idle to main, so that could be it; especially given your comment about it stalling the engine. My guess is that didn't happen at high rpm.

If no joy, move the clip down one notch and let 'er rip.

TurboT · 11-01-2009, 11:34 PM

If it makes you feel any better my YZ is doing this too, once in a while. I started it yesterday to let it run a bit and it was farting back on me after throttle snap.. could be the cold, but it might need some adjustments. Different units but tweaking never a bad thing.

MICRider · 11-02-2009, 06:43 AM

Yup, guess it would make more sense to play with the carb a bit first... Especially since it made such a drastic difference just switching to the Mik. Almost has to be carb related. Plus, I don't even think you can adjust the timing on these with the CDI can you? I seem to recall my old CT70 having points and being able to adjust the timing but that was a million years ago

. I will try air/fuel screw first, then move clip if that doesn't do the trick. Ty for the suggestions. Wont get a chance to do it tonight though, sold a couple of old streeters and the fellow is supposed to be coming to get them tonight... Yay, garage reorganization... Not! Lol!

Regards,
Stew

Weldangrind · 11-02-2009, 11:29 AM

Stew, I think that the only provision for timing on these is by Dremel or racing CDI. Like you say, it almost has to be carb related, especially if it didn't make that noise before. Good luck!

11-01-2009, 10:58 PM	#1
MICRider Join Date: Oct 2009 Location: Alberta, Canada Posts: 3,274	Occasional popping in carb? Hello, was out putting around with my son tonight for a bit. My Beast runs much better with the new Mik on it (though I still haven't had a chance to tweak it), but I still get the occasional pop/hesitation on it. It will stall the machine if it catches it just right. Funny part is that the pop seems to be coming from the carb... Is it possible that the valve lash is a little tight and it is backfiring through the carb? Or would it more likely be a timing issue? Lol, though I would have to refresh my self on setting timing (can you even set the timing on these 200cc engines?). Or... Is it just cause I don't have the carb set up right? I should probably tweak it some more and see if that cures it, does run 100 times better than it did with the stocker still. Anyone else had the popping issue? Surely does sound like a backfire through the carb throat. Regards, Stew
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11-01-2009, 11:28 PM	#3
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Maybe it's just a little lean Stew. I'd be inclined to adjust the air / fuel screw first, because it's easier. Besides, the air / fuel screw is resposible for idle and the transition from idle to main, so that could be it; especially given your comment about it stalling the engine. My guess is that didn't happen at high rpm. If no joy, move the clip down one notch and let 'er rip. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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11-02-2009, 11:29 AM	#6
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Stew, I think that the only provision for timing on these is by Dremel or racing CDI. Like you say, it almost has to be carb related, especially if it didn't make that noise before. Good luck! __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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11-01-2009, 10:59 PM	#2
MICRider Join Date: Oct 2009 Location: Alberta, Canada Posts: 3,274	Lol, I am jealous of the 110... Purrs like a kitten and never misses a beat!
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11-01-2009, 11:34 PM	#4
TurboT Join Date: Sep 2008 Location: Surrey, B.C., Canada Posts: 2,185	If it makes you feel any better my YZ is doing this too, once in a while. I started it yesterday to let it run a bit and it was farting back on me after throttle snap.. could be the cold, but it might need some adjustments. Different units but tweaking never a bad thing.
	0

11-02-2009, 06:43 AM	#5
MICRider Join Date: Oct 2009 Location: Alberta, Canada Posts: 3,274	Yup, guess it would make more sense to play with the carb a bit first... Especially since it made such a drastic difference just switching to the Mik. Almost has to be carb related. Plus, I don't even think you can adjust the timing on these with the CDI can you? I seem to recall my old CT70 having points and being able to adjust the timing but that was a million years ago . I will try air/fuel screw first, then move clip if that doesn't do the trick. Ty for the suggestions. Wont get a chance to do it tonight though, sold a couple of old streeters and the fellow is supposed to be coming to get them tonight... Yay, garage reorganization... Not! Lol! Regards, Stew
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