Help With Carburetor!

I did adjust the float level but it did not help, It would do it much more when climbing a grade because the carb would be tilted back or close to level. I have had my carb apart about ten times so far, the tube change was the fix. I don't see any reason for the bowl vent tube to vent to the air filter any way, considering the evaporation rate of fuel on hot day it should make a diff. in tuning.
 
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Greg58 said:
I did adjust the float level but it did not help, It would do it much more when climbing a grade because the carb would be tilted back or close to level.
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I did my best to install my engine so the carb was level, but there are other factors involved, so mine ended up tilting a little bit forward (like pouring into the engine). This makes that vent on the inside be even higher and less likely to be an issue, which might explain a bit why some people get improvements from pulling that vent tube and others do not. It might have a lot to do with the carb angle...

Climbing a grade makes sense, that opening is at the back/top of the carb, so if you tilt the carb back fuel will rise in that area. Although I just climbed a steep @$$ hill at 20+ MPH without any signs of problems, engine ran just as good going up the steep grade as it does on flat land (with vent tube connected). Since my carb was tilted a little forward I adjusted my float to keep the fuel level a little lower in the carb (cause the engine side is artificially high due to the carb tilt). Perhaps since I have the fuel level set on the lower side in the carb the tilt going up the hill wasn't enough to cause this problem for me.

PS it just came to mind, before I adjusted my float to lower the fuel level in the carb I noticed that the engine would die if I went over bumps at low rpm (like when I was coasting in after a ride). Perhaps this was happening cause the higher fuel level in the carb let fuel splash up to that vent and get sucked in when the carb got bumped around. This problem is gone now too, she never stalls no matter how bumpy the terrain. I had thought this change might be due to fixing an air leak, but after chatting with you I am thinking perhaps it was fuel getting up through that vent causing her to die.
 
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I just took my cns carb off and just got my nt carb so It's not my forte on adjusting carb but I could use some advice the throttle cable looks easy enough to swap but it's got a primer button and the idle screw that's where I lack knowledge should I just install it and push the primer a couple time or what would you people do,and what what about the manual choke
 
I have a nt as a back-up, I just installed it and tried to start the engine. Once it started I stoped and adjusted the idle, and let it idle for awhile then rode it as I allways do. I didn't use the primmer bulb but if it was cooler weather it may be needed.
 
What I do is start the engine and get it to idle at the rpm I want, then I adjust the air mixture screw (closest to the air filter) ccw till I get max. rpm then I lower the idle again to the rpm I want the engine to idle at.
 
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