Chinese Scooter Club

Tommy · Mon Jul 14, 2008 2:01 pm Znen ZN50QT

Hello, I'm new to this forum but I really would like to know how to de-restrict my Znen ZN50QT, I know there are three ways but which is the easiest and how do I do it ?

halley · Mon Jul 14, 2008 2:28 pm

Give us something to work with. What three ways are you familiar with? Are you sure your bike is restricted? Are you sure your bike has one, two or three restrictions? Perhaps there are more than three restrictions. Some restrictions work in tandem and must be adjusted together. Some restrictions only need to be changed alone to see a change in performance. What restrictions did you find? Are you sure it's legal to de-restrict your scooter where you live? What about the postings in this forum that walk you through several types of de-restriction?

Checking your throttle cable can ensure you're making the most of the twisting range of motion on your grip.

Changing the weights can increase acceleration on hills and after stops.

Removing a ring around the variator hub can allow the variator to close more tightly, allowing a few more RPMs if the CDI also allows it.

Clipping the RPM limiter wire on the CDI can disable the red-lining protection and allow as many more RPMs as you can throttle.

Adjusting the carburetor jets can pour more fuel into your engine as you throttle. You have to balance this with a different air flow.

Adjusting the air flow can give more air to the carburetor to maintain a proper mixture at high throttle.

I think this is more common on two-strokes but exhaust modifications can ensure proper vacuation at high throttle and avoid the limiting effect of back-pressure.

Reducing overall occupant weight and load can have an effect on top speed and acceleration. :)

Others that I'm missing?

DaveS · Mon Jul 14, 2008 3:10 pm

halley wrote:
Others that I'm missing?

A pretty comprehensive list! :)
I can think of one more, that was on mine, and has been reported on others in this forum. There is sometimes a screw inside the lid of the vacuum chamber on the carburetor that limits the travel of the diaphragm and therefore the main jet needle. I was able to notice that before I looked for it, by the throttle having no effect in the last quarter of the throttle travel. In other words, I could twist the throttle OK, but nothing happened.

Fox · Mon Jul 14, 2008 3:38 pm

halley wrote:

Reducing overall occupant weight and load can have an effect on top speed and acceleration. :)

Yeah! How much do you weigh? ROFL LOL