Race fuel

I was hoping you guys could tell me which fuel is better regarding leaded or unleaded. My freinds tell me I should only be using unleaded race fuel. The dealer said leaded is fine. A car buff freind said lead is good for the valves. I am confused and wondering if you guys run leaded or unleaded and why? I was thinking about VP red which is leaded, or Unocal 100 unleaded.


I have run klotz 112 oct. its leaded, used it in my 450 and

my buddies all year .

I mix it 50-50 with amoco premium gas.

Same plug(no lead deposits)and only had to adjust one intake


You can buy klotz gas in 5,35 and 55gal.

Look at their web site for dealer location,I am also very

pleased with their 4 stroke oil.

Hope this helps.

Steve T.

I run about 1/3 76 110 and 2/3 pump gas. the bike runs like a champ.

I currently running 100% cam4 110 octane with no problems thus far. I should note however I am running a high compression head. Previous to head work I ran premium pump gas w/o problem.

good question, i've been running sunoco 112 in my '02 crf for about 6 months with no problems at all just wondering if it will damage the bike after time opposed to pump fuel?

Correct me if I'm wrong, but I see no need nor advantage to running race gas through a stock motor? Or is stock compression high enough to justify the added octane rating (above and beyond say premium pump gas at a 94 octance rating)?

Only asking cause i ran mine with 94 for up till last week (had her since fall).

The Chevron where I live has 91 octane premium. I know the octane used is supposed to be atleast 92. If I am on the border with a stock engine I would rather error to the side of caution. I also noticed a difference in performance when I tried a Unocal 100 unleaded. It was slight but I could feel a quicker rersponse. just seemed more "snappy". After consulting with several people I know I decided to use a 50/50 mix with premium and Unocal 110 leaded.


If we had 94 octane gas I would run pump gas also.

bla, bla, bla... Just kidding Tuna! Like he said. I'm one of the buddies. :)

Like mxraceraz,

I use 1/3 race gas(VP C-12), and 2/3 91 pump gas on my BRP and CRF with no problems.

I use vp ultimate4. I don't know if it's leaded or not, but it works great. It really adds power. It will stink up your garage, so be sure to keep it in a well ventilated area. I run it 50/50 for playriding, and 100% for race day. This fuel was formulated for our bikes... AMA is considering banning the fuel. That should tell you how good it is.

I have heard that the vp ultimate4 is great for 4-strokes, however, isn't it about $8 or $9 per gallon? They say it adds 2-4 hp.

yeah, it is very expensive. It does add horsepower though. If you figure $40 for 5 gallons, its pretty cheap for 4 extra hp on raceday.

Leaded is good for the valves in your engine, because it lubricates them.

VP makes a cheaper fuel for four strokes as well. It is called 103. It has a 103 octane rating.

One advantage of using race gas over pump for a stock engine is temperature. The race gas burns at a much lower temp., so your motor will not run as hot. This does not help much on the first lap, but after that it is great. When everyone else is losing horsepower from engine heat, you won't. Or at least not as much.

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