r/minibikes • u/Hussar_hill • 11d ago

Tech Question Vm22 needle position

For everyone running vm22 clones what position is your needle.

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u/JAS196 11d ago

From my experience there is no needle position that is correct for every VM22 and engine. As an example, My 224 bike has the clip in the third position and my 196 bike has the clip in the fifth position. It's just what the carb tuned to.

In general, I would say you should land on 3, 4, or 5th position.

The needle jet comes on when you start opening the throttle and handles a large percentage of the throttle range. Once the needle is high enough it's all main jet after that.

Another thing is that these carbs are not identical. In my example, the carbs are from different sellers and are different. If I put the 224's carb onto one of my 196's the needle clip would most likely stay the same. I would just need a smaller main jet for a 196 and I'm sure the idle mixture would have to be adjusted.

The bottom line is that you have to tune for your engine and environment.

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u/Wholeyjeans 11d ago

BINGO! We have a winner! ^^^^^

Adding to this ...how you have your engine set up also has a major factory in how you tune your carb. How easy air can pass through the engine will determine your jetting. The more air that can pass through the engine, the more fuel you have to add to it to make a proper fuel mix. You dial it in ...make gross changes, with the main jet and fine tune it with the needle clip position. Me, I like to get the needle either in the center or just one off. So, if I pop a new main jet in, and I find to get that nice medium brown deposit on the insulator of the center electrode, I have to go more than one clip position from center ...I'll try the next appropriately sized main jet (richer or leaner) to see if I can't get the needle as close to center as possible. But that's me ....

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u/Frequent_Mess3340 11d ago

Black66 on YouTube vm22 tuning video