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So I recently replaced my float needles, cleaned the carbs, set float heights, and resynced. I was in the process of setting the idle mixture last night and encountered some problems.
I chose to use the propane leak method to adjust the mixture. On the two of the carbs this worked great and I was able to set the mixture where the idle jumps slightly with a small amount of propane, however, on two of the carbs there is no change when propain is introduced, and no change when the screws are adjusted in anyway.
The two problem carbs are not paired and I have black smoke out of both exhaust pipes. The bike idles pretty good, and it will idle smoothley as low as 900-1000 rpm. But if I throttle up smoothly it will hicup around 4,500 rpm and above. And smoke a lot.
I removed all of the mixture screws and discovered the two problem carb's needles have wear grooves worn into them, while the ones I could adjust are just fine. Just for the hell of it I started the bike with the needles removed and it actually ran very well, without the 4,500rpm miss.
Now the question:
Should I just the replace the mixture needles? Is this my main problem? When removing the screws does this create a lean condition? Can anyone give me more info on the screw, is in = rich and out = leaner?? Not sure how it works exactly. If I just need to replace the screws, does anyone know if it's true that 76-77 XS650 needles will fit?
Any help is greatly appreciated. Should have never started tearing apart the carbs until after the summer.
I chose to use the propane leak method to adjust the mixture. On the two of the carbs this worked great and I was able to set the mixture where the idle jumps slightly with a small amount of propane, however, on two of the carbs there is no change when propain is introduced, and no change when the screws are adjusted in anyway.
The two problem carbs are not paired and I have black smoke out of both exhaust pipes. The bike idles pretty good, and it will idle smoothley as low as 900-1000 rpm. But if I throttle up smoothly it will hicup around 4,500 rpm and above. And smoke a lot.
I removed all of the mixture screws and discovered the two problem carb's needles have wear grooves worn into them, while the ones I could adjust are just fine. Just for the hell of it I started the bike with the needles removed and it actually ran very well, without the 4,500rpm miss.
Now the question:
Should I just the replace the mixture needles? Is this my main problem? When removing the screws does this create a lean condition? Can anyone give me more info on the screw, is in = rich and out = leaner?? Not sure how it works exactly. If I just need to replace the screws, does anyone know if it's true that 76-77 XS650 needles will fit?
Any help is greatly appreciated. Should have never started tearing apart the carbs until after the summer.
(actually his was the Mitubishi Starion, but same thing) Wow did that car fly. I wish I could have gotten that car from him. Instead I ended up with a Honda Prelude 
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