What VP racing fuels are legal for the supersport series races?
Yeah, what he said.
U4. Go ahead and call VP and they can square you away with your needs.
Mark
thanks for the help
Virtually everything that is considered gasoline under ASTM is legal. This would include fuels with massive amounts of oxygenates. Nitromethane and methanol would not be legal.
Is anyone thinking of an alternative to VP? I've heard they are changing to the 4.2 version and you have to get mapped for it. Unlike the 4.0, your bike will not run well on pump gas after you have the 4.2 map included.
Sure, I've used Power Mist for years. They have something new in the works.
They've even made me special mixes.
I can never tell if you are joking.... where do you get it, what is the octane and any other info you might have. I'm looking for a cheaper alternative.
http://www.powermist.com/home.html
Thanks...for the alternative and link..
Personally, I love the new U4.2. It doesn't stink, it doesn't clog everything up with gook, it burns cleaner. It made more power for me on the dyno. I was disappointed when I couldn't find any at Daytona.
I don't think there's any race gas that'll work ideally if the bike is mapped on pump gas. Every brand of fuel has a different MON, they all have different specific gravity. If you bike is stock and has low octane (MON) requirements, I'd recommend having it mapped on a low octane race fuel. From there, you can experiment with different pump fuel brands. That way, you'll have known consistent baseline to go back to.
Also, if you live anywhere north of Kentucky and west of Indiana, the "pump" blends change with the seasons. To reduce smog, most brands increase the amount of ethanol in the summer. As Dave said, there are other brands out there besides VP. I used Klotz last season, but my cheap source dried up. If the bike is stockish, I'd avoid the higher octane stuff. Stick with something around 87-94 MON. Note: pump gas is rated with (MON+RON)/2, which is a crappy way to rate fuel. Almost all race fuel is rated with MON.
Thanks for the input 123user. Last year was my first season racing and i competed on a pretty stock 1st gen sv650. This year I'll be racing a 749s that will fit into the stockish category and want to compete in the middleweight along with super twins. I know its a little heavy and down on power compared to the current 600's so that's why i was interested in using some type of race gas instead of pump gas. Right now my bike is at the ducshop in atlanta getting some work done to it. So they are going to call me and give me some ideas as to what i should and i was looking for some other opinions. Once again thanks for the advice everyone
The 749 might require a different fuel than an in line four. The sheer size of the combustion chamber makes life different. Think about it, each cylinder has more displacement than a GSXR1000 cylinder. When they are pumped up, a bigger twin, the can require more octane than what one would need with a 600/4 etc.
The Ducshop guys will have some good ideas. Listen to them. Use their prior experience to help you out.
If your trying to keep the costs down and don't need oxy-fuel, either VP marine, or Motorsport 98L are good options. While the 749 has a significantly larger bore size than a 600, its still not enormous, the boundary area is significantly less than an RC51, TL, or 998-series. Also, the combustion chambers on these are pretty good. Any modern PentRoof type combustion chamber can handle very low MON numbers.
If money is no object MR9 is good. I ran some in my Duc at RA this summer. Even with the old hemi-style two valve chamber (and 300F oil temps!) in ran great with no signs of detonation. I'd be a little wary of using either MR10 or MR11 though, depending on the compression ratio.
I don't know if the S-model 749 runs the "Strada" cams (base model, shorter duration) Still, many of the older (design)- desmoquattro headed bikes (748, 749, 888, 916) run larger duration cams than the testaretta. The overlap typically reduces peak pressure significantly- Long story short, any race fuel aught to work ok