Jayraye39
Well-Known Member
- Local time
- 2:17 PM
- Joined
- Jul 13, 2021
- Messages
- 856
So I had a flat out genius idea I have a vm-20 clone carb and it's very hard to find jets for it I've read it actually takes Kiehine main Jets and a Mikuni pilot jet. however I did take a chance as my bike was running way too rich and I soldered the main jet to make it smaller but to my dismay it was still about a 130 jet. After adding my KX85 expansion chamber that jet was now way way too big. So what I did was got welding tips from Harbor Freight. The cheap ones. I got a .035 and a .030. Now even though those are the numbers that you see that's not the actual diameter of the hole. They are a tad bigger than what is written on the tip. The conversion for a .030 welding tip is actually a .0437. I know this because I have a handy gauge measuring tool. I took that measurement and matched it against a diagram online on Keighn jet sizes. it turns out that a .030 welding tip is a number 113 jet the and the .035 welding tip is equivalent to a 125 main jet. Now I did have to do some modifications to the tip as they were too long and the threads were too wide and did not match so what I had done was stuck my .030 Welding tip into a drill and ran the threads along a file. Evenly sanding them down. once the threads were gone and the dia. was enough to fit inside the emulsion tube. I grabbed a pair of pliers and held the emulsion tube. Then wil the tip still in the drill I force the welding tip into the tube until it's seated properly. Once in the tube I took it over to the bandsaw and chopped it down to the proper size . I sanded the rough edges clean and put it back together in the carb. now have a properly jetted bike with a 113 Main Jet. here is pictures of what I did. Since everybody's having a hard time finding main jets for this carb I'd figure I'd share what I did. here's the chart for a conversion as well
