infinity999
Well-Known Member
So I rebuilt my carbs a couple of weeks ago. Tanked them, sprayed carb cleaner through everything etc. Also replaced all gaskets, o-rings, etc. I did notice that there were aftermarket needle valves in the carbs so I went ahead and put it back together, adjusted the mixture screws to 2.5 turns and tried to sync it. Exhaust had a very strong smell of raw fuel and I could not get carbs 3 & 4 to do anything with the screws turned all the way in. It seemed to me that the needle vavles were not working correctly and the carbs were being flooded..
So I ordered new Yamaha needle valves, installed them today and it's the same issue. You can turn the mixture screws all the way in on carbs 3 & 4 and the bike just keeps idling. The strong gas odor is gone though. I have not done a wet check on the floats but they were adjusted lining up the circles etc. The idle isn't too bad but it does jump around a little bit. I am beginning to wonder if carbs 3 & 4 are not idling on the idle circuit? Could it be something with the linkage between carbs 1/2 & 3/4? Turning in the mixture screws on either 1 or 2 will make the engine stumble and die.. Any ideas? Thank you.
So I ordered new Yamaha needle valves, installed them today and it's the same issue. You can turn the mixture screws all the way in on carbs 3 & 4 and the bike just keeps idling. The strong gas odor is gone though. I have not done a wet check on the floats but they were adjusted lining up the circles etc. The idle isn't too bad but it does jump around a little bit. I am beginning to wonder if carbs 3 & 4 are not idling on the idle circuit? Could it be something with the linkage between carbs 1/2 & 3/4? Turning in the mixture screws on either 1 or 2 will make the engine stumble and die.. Any ideas? Thank you.