wrd17 wrote on 10/29/08 at 11:47:42:My bike is running very rough, it takes almost full throttle to get it started, dies when I idle down and lags when given gas. If a bike is running rough in this manner can anyone tell me if it is running to lean or too rich.
Your low throttle range (pilot circuit) and possibly the midrange (jet needle/needle jet circuit) are clogged up.
In order to get enough fuel and air into the engine for it to fire has required you to open up the throttle into the high range (main jet circuit), which shows that the low and/or midrange are NOT providing enough fuel &/or air. So soak it if you wish in sea foam or what ever, and then give it a try. If it works good afterward then great, if not, then pull it off the engine and take it down to every screw, jet, washer, o-ring, etc, and clean every single passageway in there. I spend up to several hours if needed to do that. I am working on a carb now and took over an hour to clear just one passage, the one in the small brass tube sticking down into the float bowl and has a hole that is only 0.37mm ID. That passageway goes up to the choke/enricher and is also connected to the pilot circuit so it affects both.
Have you noticed the tiny hole on the intake side of the carb ? It is the same size as the other I mentioned (0.37mm ID) and connects directly to the side of needle jet bore, supplying air into that midrange system. Ever notice the tiny holes on the sides of the needle jet? That is where the incoming air gets through to help control the fuel for the midrange.
Can you imagine how small of a particle of dirt or carbon buildup it would take to clog that up? I just now went to check the carb I am working on and spent 15 minutes clearing this passage ... it was clogged with carbon/dirt... before it was clear enough to blow carb cleaner through it freely.
Point is, every passage is essential for PROPER CARB FUNCTION.
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