I recently acquired a 79 special II, but I am still having issues with the carburetor or possibly fuel delivery. The carb has been thoroughly soaked and reassembled. The diaphragm slides were not moving very well so after a little scotchbrite, and discovering that the needles were slightly bent, we got them to slide no problem. I had rigged up a funnel to some 1/4” fuel line to see if she would run. Got it for a second or two, then it would die. Electric and kick start. The butterfly’s are at 22mm, and I believe the rest of the carb settings are at stock. There must be something I’m overlooking because it’s ran and revved up, and even was able to ride it for about 50 feet in first gear. Happy to provide any further photos or info to help.
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79 Carb Issues
- Thread starter Murraw
- Start date
Those are carbs for the 80-82 sohc bike. My guess is you have a 80-G model. Pilot mix screws should be around 3 turns out and the floats should be set to 26mm (brass ones). Sync the carbs with a manometer. Is the bike full stock? post pics. If your slide needles were bent you will need to replace them as that will cause metering issues. Did you replace the pilot jet rubber plugs? The float valve o-ring and needle?
They were slightly bent, got it to run but only while on the throttle today. Are these the pilot mix screws in the pic? Not sure how to adjust them. Only things replaced were the gaskets, the rebuild kit was the basic one from mikes xs and it didn’t seem like the parts matched up.
Attachments
Under those brass caps are the pilot mix screws. There are threads on how to remove them or google mikuni bs34 pilot screw cap removal. Make sure you have the stock intake air filters and boxes on the bike when your tuning it. It will make a huge difference. Bike is a 80-G I have the same bike.
