basically everything works fine off the line til i hit ~20 at WOT then it sounds like its 4 stroking a bit and i cant really accelerate anymore. I know 4 stroking is caused by too much fuel in the engine but even at WOt up until i hit ~20 mph it sounds perfect. i am running a 44t on the rear so i may just be topping out. but it feels like it wants to go, just cant. i moved my c-clip up one notch at it was running WAY too lean, so im outta ideas, any help?
4 stroking at WOT sometimes
- Thread starter crobo
- Start date
http://motorbicycling.com/f3/stock-carb-question-16982.html#post165969
no matter the thread - it's gonna be the same answer lol
awake: i realize that these engines are always going to 4 stroke a little, my question was is 25mph about the top end for a 44t sprocket on a 66cc motor? and if that's the case would it sound like it is 4 stroking once it hits that mark?
venice- im runnin 4oz of oil to 1 gal of gass which is 32:1 im pretty sure. im on my second gallon of gas now, the first gallon was 16:1.
venice- im runnin 4oz of oil to 1 gal of gass which is 32:1 im pretty sure. im on my second gallon of gas now, the first gallon was 16:1.
Don't worry about it 4 stroking until you have about 4 gallons through it; it will keep running better & better the more it breaks in.
No crobo, provided we're talkin' about a 44t ona 26" wheel - 30-35mph is the norm for a stock kit (speeds vary due to other considerations).
As we've said, these engines are prone to four-stroking in any/all rpm ranges while they're still new, and most likely will continue to do so no matter their mileage when not under heavy load.
If yer still on yer second gallon of fuel - the motor is essentially still brandy-new. Not only do these things consume far more fuel when new than later when they're actually broken in - you may well have fouled the plug with deposits from running as heavy a mix as 16:1. It's not yer fault, it's an "error" in the instructions believed to be the result of a lack of common availability of quality 2 stroke oil o'er there, 32:1 is much better.
As has been said bfore - provided ya know yer not runnin' too lean (which four stroking is not a symptom of), it's best to just leave the carb alone till you have at least 200mi on the thing - my Schwinn build took almost 300mi to snap outa it.
These carbs run rich - it's tru, but untill the engine is broken in you'll just drive yerself insane tryin' to "fix" it
As we've said, these engines are prone to four-stroking in any/all rpm ranges while they're still new, and most likely will continue to do so no matter their mileage when not under heavy load.
If yer still on yer second gallon of fuel - the motor is essentially still brandy-new. Not only do these things consume far more fuel when new than later when they're actually broken in - you may well have fouled the plug with deposits from running as heavy a mix as 16:1. It's not yer fault, it's an "error" in the instructions believed to be the result of a lack of common availability of quality 2 stroke oil o'er there, 32:1 is much better.
As has been said bfore - provided ya know yer not runnin' too lean (which four stroking is not a symptom of), it's best to just leave the carb alone till you have at least 200mi on the thing - my Schwinn build took almost 300mi to snap outa it.
These carbs run rich - it's tru, but untill the engine is broken in you'll just drive yerself insane tryin' to "fix" it
I had the same problem until I fitted an expansion chamber on my bike. Now it revs so high I have to back off on it. By the way it's the 50cc gen-2 grubee with the pocket bike carb and the steel sleeve.
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