I've got a 02 SV superbike with lots of aftermarket stuff. Here's my question? Is performance affected by temperature changes (50 degrees vs. 70 degrees)? Anybody rejet depending on the season? I rode the bike for the first time in Oct. and it was awesome. It did have a power surge around 7K but was not that bad. Top end performance was great. Temp was about 70. Fast forward. I rode the bike at Jennings Fl in early Jan. and it was about 50-55 degrees and the bike was a little lackluster at low RPMs but then hit like a freight train at 7K. Not the best feeling Also I changed from VP to Nutec (only because Nutec is easier for me to get) Does it sound like a needle height issue or a main jet issue? The bike has a Yoshimura carb kit with Stock filter an Full race Micron. (I'ts not backfiring or smoking so I'm not inclined to think either rich or lean) I can ride it like it is but I could ride it better if the power was more linear. Thanks in advance for any input :up:
Check your jetting. I have flatslides on my sv superbike and always need to adjust for florida. (Daytona.)
VP type I believe the racer I bought it from used Ultimate 4. I have a friend who sells race fuel so I have been buying Nutec "Mad Dog" from him.
I know Nutec Special 5 and Special 5, but I am not familiar with "Mad Dog". Could you please elaborate?
I found out that "Mad Dog" is Special X which is what I believe Nutec is selling to compete with Ultimate 4. They are both oxygenated. That is what I wanted to find out. It sounds like the bike is lean due to the drop in temperature. I would try picking up the needle for the cold weather. Also where the bike is running much stronger on the top in the colder weather you might be rich on the main for the warm weather.
Thanks for the input. The lean low end is my guess also. I'll make some test adjustments this weekend.
One thing that MIGHT be causing the top to be a little rich is the switch in fuel. I believe that the Ultimate 4 has a much higher oxygen content than the Special X.
Another person told me that temp AND elevation changes between VIR and Jennings would add to a low end lean condition.
I think I got this figured out. My SV has the Yosh carb kit which, I think, helps mix the air with the fuel better. Anyway, I took the carb slides out to raise the needle and discovered that the slides where moving slloooowly. The fuel spray must have collected and gelled in the slide channel. It looked like it was lubed with molasses. I cleaned it up, sprayed a little WD40, raised the needles a clip and fired it up. I won't know for sure until Friday but it seems to rev quickly now with no hesitation.
