Idling and acceleration

Snazzy Razzy Mazzy /

Hi guys. I have a question from somebody who knows NOTHING about engines... ok here goes.

I have an old 1970's moped. It runs great, but when it's idling, the back wheel spins like crazy. For instance if it's on the center stand and the engine's running, the wheel is still turning really fast (without giving it gas) unless I hold the brake. This isn't really a problem, because if I'm sitting at an intersection or something, my weight keeps me from speeding off involuntarily (obviously).

Also, the acceleration is terrible on the thing. It takes a while to get going from an intersection or whatever. But when I do get going, it's great! 30 mph.

Anyway, somebody told me that what I should do is fine tune the carburator. Apparently there's two jets that can be adjusted with a screwdriver and can be set in a delicate balance to increase acceleration and allow the bike to idle properly.

Does anybody know what I'm talking about? Does this make sense? And if so, how would I find these jets to make the adjustments.

ANY help would be greatly appreciated!

Thanks in advance!

Re: Idling and acceleration

First, what kind of moped do you have? That makes a huge difference. If your iddle is really fast, you might try tuning your throttle. On a Dellorto carburator, there's a screw on the left side that can adjust the throttle. My Bianchi also has a small screw-like thing where the throttle cable goes into the handlegrip that can be turned also. Either or both of those shoul be used.

Of course, your moped might have a different system. Again, post w/ what kind of moped you have a bit more specifically and someone else might be able to help you much more.

Re: Idling and acceleration

Snazzy Razzy Mazzy /

Sorry. It's a Batavus Bronco.

Re: Idling and acceleration

Hi, I have the same moped! OK There are two screws on the left side of the carbeurator, as if you were sitting on the bike. One should be bronze and the other should be metal colored. You can start the bike up and have a friend hold the back brake and turn the metal colored screw to the left in small increments untill it idles normal. Good luck if you don't understand ask again

Re: Idling and acceleration

Snazzy Razzy Mazzy /

Hi kamran! That's cool that you also have a Batavus!

Anyway, pardon my ignorance, but can you tell me specifically where the carburator is (what it looks like, how I find it). I want to make sure I'm turning the proper screws! Do I have to take the engine apart or can I just do this easily without messing with anything.

Thanks again!

Nick

Re: Idling and acceleration

its very easy. The carburator is down near the bottom of the bike. look for the grey pulley there should be a hole in it, And the carb is behind that pulley. you should be able to see it through that hole. when you get that hole lined up with the carburator thats where you will see the two screws. turn the metal colored one to the left until it idles right. good luck and if you have trouble post another message!

Re: Idling and acceleration

Snazzy Razzy Mazzy /

THANKS! I've got it idling great! Now the back tire just moves ever so slightly... beautiful!

Now i just have to work on the acceleration problem. The other screw, does it control the fuel/air ratio, and if so would this have an effect on my terrible acceleration. As I said, when I'm up to speed, the moped runs like a charm but it takes about 30 seconds to get moving to a speed where I can keep up with traffic.

Thanks again for your help!

Re: Idling and acceleration

Im not shure about the accelaration, but i'll think about it.

Re: Idling and acceleration

Snazzy Razzy Mazzy /

Great, thanks!

Nick

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