Dirtdame
Member
- Apr 10, 2010
- 146
- 0
I own a 1986 KDX200 C1. I bought it new in September of 1985 and have had it almost all this time, except for a couple of years when I sold it somebody else but then bought it back. I have rebuilt that engine from top to bottom a couple of times and have always kept it tuned and jetted properly.
A month ago, I came across a basketcase bike just like mine for cheap, so I bought it to restore. I got it to run after a carb clean, but it ran pretty bad, loading up and smoking awful, so I decided to rebuild the engine. New rod kit, main bearings and seals, flex honed the cylinder, put in a set of reeds, fresh piston kit. All nice....go to start the engine and the bike still was running terribly rich. It is strange because the carb was jetted very lean compared to my original bike's carb. It had a pilot jet that was two sizes smaller than the one in my other bike, the needle was dropped all the way and the main jet was smaller too. I dipped that carb, checked every jet and piece that went in it, made sure that the floats were good and levels adjusted right, checked the fuel valve needle o-ring and fuel valve needle (physically on the bike with the gas tap on), made sure that the choke assembly was operating properly and wasn't leaking when closed, but the bike is awful with that carb on it.
Then I took the carb off my good running bike and put it on the freshly rebuilt one. Guess what? The bike ran perfectly. I took both carbs apart and double checked all the parts. Both had the same needle jets and needles. I put each carb back on the machine it came off of. But I don't get it. The carb that is jetted lean runs so rich that the bike won't even idle. The other carb runs perfectly. Grrrrrr. I think that there must be something wrong with the carb body on my rebuilt basketcase, because theoretically I should be able to jet it identically to my other carburetor and have it run identically to that carburetor.
Any insight into this?
A month ago, I came across a basketcase bike just like mine for cheap, so I bought it to restore. I got it to run after a carb clean, but it ran pretty bad, loading up and smoking awful, so I decided to rebuild the engine. New rod kit, main bearings and seals, flex honed the cylinder, put in a set of reeds, fresh piston kit. All nice....go to start the engine and the bike still was running terribly rich. It is strange because the carb was jetted very lean compared to my original bike's carb. It had a pilot jet that was two sizes smaller than the one in my other bike, the needle was dropped all the way and the main jet was smaller too. I dipped that carb, checked every jet and piece that went in it, made sure that the floats were good and levels adjusted right, checked the fuel valve needle o-ring and fuel valve needle (physically on the bike with the gas tap on), made sure that the choke assembly was operating properly and wasn't leaking when closed, but the bike is awful with that carb on it.
Then I took the carb off my good running bike and put it on the freshly rebuilt one. Guess what? The bike ran perfectly. I took both carbs apart and double checked all the parts. Both had the same needle jets and needles. I put each carb back on the machine it came off of. But I don't get it. The carb that is jetted lean runs so rich that the bike won't even idle. The other carb runs perfectly. Grrrrrr. I think that there must be something wrong with the carb body on my rebuilt basketcase, because theoretically I should be able to jet it identically to my other carburetor and have it run identically to that carburetor.
Any insight into this?
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