Since I got my bike (96 Suzuki RF900) and got to know it, I've thought it was running rich.
I think this for a few reasons, people have told me it lets out a puff of black smoke when I really nail it, the midrange seems a little doggy, and when you hold the throttle open in a high gear for a while then roll off a bit, it feels like I actually begin to accelerate faster. Not to mention the heavy soot in the outlet of the muffler.
OK, so I took the carbs off and took the bowl off one of them. The main jet is a 118, which is larger than the largest factory jet which specifies a 115 for the German-spec'ed model.
Mine is the USA spec which I think calls for a 112.5 main jet. I'm not 100% sure of that because for some reason, the Suzuki repair manual I have does not list the USA-spec bike. But, the 112.5 main jet is most common on several models including the Canada spec.
So, it would seem someone has re-jetted the bike, but I don't know if the needle is different, or if the CV slide spring has been changed, etc. I can't ask the previous owner because he's deceased - was when I bought the bike.
The bike's pipe and muffler are stock, afaik
, but it does have a K&N filter in the stock, unmodified air box.
The question is, do you think I should just try a smaller main jet (maybe the 115) and put the needle back to the stock-recommended 3rd notch down because it's currently 4th notch, and give it a go?
Or, just get a complete different jet kit (DynoJet?, Factory Pro?, Ivan's?) to put in so I know what I've got for sure?