Re: My Suzi T500 Project (Finished Video & Pics!)
John, Fantastic build. Really like the pipes. From everything you have reported so far, you have been and still are rich on the pilots. Have to admit, seems odd as you are pretty small now. Couple of things. Are you still running your vent lines and can? Remove this if so, at least until you get it sorted. Also, where are the jets from? Get some authentic Mikuni jets if yours are not the real McCoy. Some replicas can be way off. Otherwise, go through and re check all the obvious stuff for leaks and proper assembly. If you have not had the carbs apart completely, maybe you should just to be sure the is no restriction in the pilot air system. Also, check the emulsion tube style. If it is solid, you may want to consider going to the alternative type with the vertical columns of holes. Down the road though, as you should get it closer first. Lastly, there is absolutely no question as to how profoundly the pipes and porting can afflict the low end. I recall a drag motor I built a long time ago much like yours. Big carbs, very heavy porting on a piston port motor, and pipes aimed at max power and high rpm. Wicked power (10's on an AC 350), but absolutely no idle below 2500rpm. VERY hard to start with the kick, but easy if you got the motor to spin up to 2500! At Idle, you would have fuel dripping off your hand if you held it near the intake. This thing was as lean as I could get the low speed circuit, but the tuning made the reverse air flow through the carbs so bad at low revs that it was essentially double and triple dipping the low speed system and making it super rich a low speed revs. I remember similar no effect on the air screws like you are having. You could actually see a fog hanging in front of the carbs at "idle"! Looks like your situation is far less severe, but there may be only so much you can do. There is a reason for restrictive reed valves! At the end of the day, looks like you have had definite improvement going leaner. Needing 2 1/2 turns out of air to see effect means you are still too rich, or there is something besides jetting making it so. One last thing. Forget all the carb tuning except for the mains until you are happy with them. Get the mains right first, as they (like all the other parts) do in fact effect the entire rev range to some degree. If the mains are rich, it may seem to run pretty good because the lower revs are so awful. Forget that. Get the wide open very close first. There is no sense in compounding the much more difficult low end and drivability tuning on a two stroke!
best