Lugging/bucking/bogging at low speeds

[outatime88]

So I started my first build(66cc) with a 36 tooth sprocket and haven't ridden with any other kind. At low speed which I guess is 9-12 mph and lower(I don't have a speedo) I get a lot of jerking back and forth, it's not too violent but pretty substantial amount. Is this normal for a 36t, I mean when I pull the clutch in the engine runs good and when I'm going pretty fast it's fine, but any time slowing down or speeding up at low speeds its there? Or could it be carb related(I'm running 16:1)?

Also not sure if it's related but the jerking is the same jerking I would get if I were to leave the choke on too much.

 

[crassius]

these all do that - 2-stroke won't run well at slow speed - with that tiny sprocket on back, you'll find it worse than usual

 

[outatime88]

these all do that - 2-stroke won't run well at slow speed - with that tiny sprocket on back, you'll find it worse than usual

Even if it's throwing itself back and forth pretty crazy like? Is there any way to at least reduce it like would going from 16:1 to 24:1 perhaps? Or new spark plug?

 

[Street Ryderz]

Even if it's throwing itself back and forth pretty crazy like? Is there any way to at least reduce it like would going from 16:1 to 24:1 perhaps? Or new spark plug?

If your just doing the break in 20:1 works fine and will help a bit but that gear is not best suited to off idle speeds the load tries to over come the engine and that's not good for your drive line or frame.

 

[motorizedbikeguy]

Even if it's throwing itself back and forth pretty crazy like? Is there any way to at least reduce it like would going from 16:1 to 24:1 perhaps? Or new spark plug?

That's what happens when your engine can't produce the torque required to accelerate. Search the forum for ways to improve low-end torque. Little things can be done here and there to reduce the amount of peddling you have to do without having to go with a larger sprocket.

 

[FurryOnTheInside]

Is there any way to at least reduce it like would going from 16:1 to 24:1 perhaps? Or new spark plug?

Yeah open the damn throttle? It must be barely off idle to get under 12mph?

Idk you might want to use a much larger sprocket so the engine can turn at a more happy speed. Retarding the timing should help at all speeds. You should definitely check your chain and engine mounts now too.

And I use 24:1 anyway (it's synthetic, 20:1 if it's dino); it'll still spit from the muffler but maybe won't fill it. Use an NGK plug and boot, and a new wire of course.

 

[gary55]

For f***s sakes have you ever drove a car with a clutch? I'm 12 yrs. old I'm on my uncle smokie's farm, All my other uncles and my dad are in the back of the truck, two cousins sittin right next to me waitin for me to f*** up so they can drive my uncle says let it out slow and give it some gas., get close to the section line then turn around and head back towards the house If you aint doing it right it don't work. Think.

 

[Kyle 47mph arizona]

Basically it jerks backwords because ur motor is stopping... u need a bigger sprocket or pedal harder before u go i run a 22 tooth sprocket thing knocks me off the bike if i go too slow... also if ur back sprocket is not perfectly concentric it will make this problem worse. Meaning when u spin the rear tire does the sprocket look like a circle or an oval... oval= bad