Race gas. What's the sknny?

Ok. I'm new to this board and therefore, I'm sure it has been discussed already. What is the pros and cons of running say VP C12, or any othe rtype of race fuel in my 00'WR400F? It has been my understnding that something with as much comp that the WR/YZ's have, high octane fuels are needed to burn cooler, less detonation, etc.


Good News! According to all who know, race gas is not necessary in YZF or WRF. 91 octane pump gas is actually preferred. Something about race gas having greater corrosive characteristics, and creating leaks in carb seals, etc. Evidently, stock compression is not high enough to matter much. If you have modified, though, all bets are off.

As you can tell from the price, race gas is much higher quality fuel than standard gas. The octane rating on race fuel is much more consistent than that of normal fuel and it burns much, much cleaner. Your bike will run fine on super unleaded, but race gas doesn't hurt. Depending on how much spare race gas my buddies race team has laying around depends on the percentage of race gas I run in my bike. If you have to buy race gas C12 is probably the best. Eric

I've tried just straight pump gas and then went to 110 octane, mix it 3 gal's of pump gas to one gal of race gas...makes it about 102-104 octane..

01 wr-426 runs much, much better...well worth the time it takes to go buy race gas and mix it...


After having spoken directly with a member of a prestigious Race Gas Manufacturer last year. I stopped paying $45 per 5 gallon can and began buying 108+ octane booster by Turner Labs at his recommendation. The Chemical comp is the same and I have achieved the same result without shoveling the money away. I have found the product is carried by most AutoZone's around the us. It sells for $10 per can and makes 30 gallons of high octane rippin power. (5.1 oz per 5 Gal can).

I have run this mix in my WR for the last 12 months with zero side effects. I recently had a friend bum a hit off my fuel can....before he returned to the trailer he was amazed at the snap the fuel alone brought out of his DRZ.

I'm happy with it.

Bonzai :)

I've tried race gas in my old CR250 with great results. I noticed how much better the idle was with it and also noticed a substantial gain in power. I've also tried race gas in my WR426 and can't tell the difference mixed or straight. I wish it did give me more but from my own expierence I couldn't tell the difference. Some guys here will sware by it and I would love to feel the difference but for now I'll keep buying the crap on the corner for about a buck!


Hey guys, thanks for the info. I have a 00' WR400F. My first Thumper. I have used both 92 pump and VP C12(108) and have only noticed that starting is a little easier on the VP. I haven't noticed any extra "snap" in the bike however (as if it doesn't have enough already). So, I guess I'll just run whatever's in the garage at the time.


Thanks again.

The main reason you didn't notice a difference is you didn't compensate for the richer running fuel. This is where a lot of race fuel misconceptions come from. Statements like "my bike ran worse with race fuel" are due to unrealistic expectations, using the wrong fuel for the specific application, and not setting up for the fuel properly. Race fuel *can* be a wonderful thing. Ever wonder why VP makes about 20 or so different fuels? The C12 is a very good fuel but your overall jetting needs to be leaned a bit to take full advantage of the fuel.

IF you decide to run race fuel, you should compensate for it and stick with it. Otherwise, you may very well be better off using a good quality pump gas (Amoco premium, etc) and sticking with that.


I like to run race gas because of the consistency. As you know, living in wonderful So. Cal., we are subject to many additives to our gasoline. Within the last couple of months, the highest octane we can get is 91. Just because the pump says 91 octane, that isn't always what you get. The bikes will run on pump gas but.....you get what you pay for.

I run Unocal 76--110 octane (the official fuel of Nascar) which is very similar to VP C-12 in all critical areas. It is usually a bit cheaper than C-12. The lead in race gas helps to buffer the valve train.

Jetting changes are usually required (leaner) when running race gas. If you don't re-jet you are not gaining the full potential of using the race gas.

All of this nonsense about race gas being no good for the pumper carbs or the fourstroke engines is foolish. I have used race gas in my YZ-F's since I got my first one at the end of 97. I have never had any problems with my carbs. Does Timmy Ferry run pump gas???...I don't think so!!


I run VP C14.....I think the stuff is great!

Do I notice a big difference? Other then the price - No - but it is all I've ever run it the beast. After messing with the jetting to acheive some form of JD/Taffy spec's - my bike runs crisp, clean, and strong. I wouldn't change.

A good racing fuel out of 5 gallons cans (don't buy the bulk stuff) is just very consistant tank to tank. You won't get that out of the pump. Don't get me wrong - there are lots of fast thumpers out there running pump gas, but why not pop for the best??

I would not use additives.....however - too many varibles, and I've read some well versed engineering opinions that are very set againist them. My $.02.

I can't find the issue, but I seem to recall a very recent issue of Dirt Rider that had a pretty comprehensive discussion of race fuel vs pump gas. Worth a look.

I am sure the jetting is different as octane increases. I am convinced the power is also better. I just don't know how much. It would be interesting to know if someone finds any dyno results, etc by race gas suppliers.

I pay very close attention to threads like this, I race, (actually Road Race), 750 SuperBike, SuperStock and Mod Prod, I ride my WR426 in SuperMotard trim to stay alert, I try to slide it into every corner I enter up in the canyons of So. Cali. I run Race gas in my race Bike (moderately modified 2001 Suzuki GSX-R750)..... with pump gas (Chevron Supreme 91 Octane) I get 131 rear wheel HP, on VP-MR1 I get 134.8 RWHP, On Neutek I get roughly the same and on F&L Race Fuel I get roughly the same, I have tested all of these fuels on the same Dyno with the same competent operator at the controls. There is REAL Power in Race Fuel when the bike is set up for it, my race bike is fuel injected and installing a new map is really easy. The price difference between all of these fuels is incredible, Neutek is roughly $19.00 per gallon for the highly oxygenated version common to most superbikes at the tracks, the VP is about $14.00 per gallon, the F&L costs me $7.00 a gallon, Chevron was as high as $2.09 for Super this summer at its peak (for me here in Cali) and is now around $1.09. My point is that my race bike ONLY sees a realistic 3HP gain at best, (from 130,131 to 133,134 thereabouts. I have NOT done a single dyno run on my WR, but I have dozens of friends who all share the same performance increase in there machines at the track and it NEVER go's above 2-3 HP gain MAX.....EVER! so that brings us back around to the WR and its single lung....beefy as it is I cannot see any way that the use of these fuels would yield a performance increase any better than those we see on our 4 cylinder engines at the track. So the question then becomes is it worth it to spend $50.00 (average) for 5 gallons of fuel you will burn up in half a day just for fun maybe realizing 1 or 2 HP (I doubt it would actually be that much but for converstation sake lets just say)? I dont think it's worth it so I am saving that $100.00 per weekend (roughly) and looking into a big bore and (poss.) stroke kit... sorry for rambling here...but I really dont see any real value here unless you are actually racing where EVERY pony counts.

Just my 2 peso's.......thanks for tolerating me!

Originally posted by yzernie:


Does Timmy Ferry run pump gas???...I don't think so!!


Good point. I usualy have VP C12 and or 76 around for my PWC. They both run very well. I have even used VP unleaded 103 in my WR and found it ran/ started great. I haven't messed with the jetting. It's still @ the stock settings. Any tips on what i should be running it at?

It appear's TeamScream and SFO have the same result's, I believe SFO did a very well documented report with results of race vs pump gas. With his stroked & bored WR, jetted for each aplication. If I recall the best he was able to get was also 3-4hp increase with his HIGHLY modified WR and race fuel. I think he is in Baja about now getting hitched/married. he has been more than happy to share his work and dyno results with all who are interested.


I guess we all have our priorities. I don't think it's worth it to rejet the bike and spend 15 to 20 dollars per tank to get a more consistant burning fuel. Call me foolish but from what I've been told by a few Yamaha mechanics is that these bikes were meant to run on good ole pump gas...

I use Phillips 66 B-32. My bike ran fine and I had no problems with pump gas. But, I believe that the race fuel is of a much higher quality and the high lead content can't hurt either. I feel that my bike starts much easier and runs crisper.

I did have to lean the jetting just a tad, but doing this is no major ordeal. Most of us have to change jetting for changing outside temps anyway.

Cost? Not even a concern with me. Not because I have a lot of money, but because I want the highest quality fuel I can get. Forest Gump would say that pump gas is like a box of chocolates.....you never know what you're gonna get. With race fuel you do.

where did you find the phillips 66 B-32 gas?..what is the octane?..price??..just curious..ive been paying 5.50 a gallon for c-12

To my mind, there are three reasons to use race gas. # 1 is tangible and noticeable, the other two require work to get the (minor) benefits.

1. Consistant Octane and quality. Unless you have a good supplier that has a good turnover of premium unleaded fuel, then race gas may help to maintain consistent running from one tankful to another.

2. Timing. Race gas gives you the ability to advance your ignition timing to take advantage of the higher octane and therefore run a richer mixture and thus have more energy released from the denser charge to push the piston down, with more power at the wheels as a result.

3. Density of mixture. Related to the above #2. If you can cram more fuel/air in the correct proportions into the combustion chamber and ignite it at the optimum point, then you will get some more power. Race fuel is more energy dense.

Both 2 and 3 above need work such as jetting and a modifiable ignition to realise the full potential. The full potential will be a few horsepower, and most of the riders out there would be better off spending their race fuel money on fitness classes or suspension tuning to get a better 'performance' boost, one that will be seat-of-the-pants noticeable.

Sure, if you have a lot of money and time, you might like to dabble, but then why not get some trick EFI setup and you will surely have more potential to increase noticeable horsepower. You could also experiment with alchohol blends and that will be cheaper and provide similar 'benefits'... Besides, consider that the 2 or 3 hp gain you work so hard to get is only at high revs, you may get 1/2 hp down low... If you spend your time desert racing it may be good, but around a track or on a trail, how could you tell?

The WR has a high compression of 12.5:1, but Premium unleaded is more than sufficient. Save your money and buy more stickers or something else proven to make you bike go faster... :)


[ January 13, 2002: Message edited by: yamaha.dude ]

I get it from Mandy's Racing Fuel in Houston. I buy it by the drum and also sell to other riders in the area to help pay for my fuel. The last time I filled the drum it was 3.75 per gallon.

The octane is 110.


Try this article if you want to learn about race gas vs. pump gas. Listen to MX Tuner & yamadude. Octane does not equal horsepower. Octane is only to stop denotation. If your bike does not denotate on pump gas, then it's ok. You only get a benefit if you change the jetting and timing. Save your money. Have your suspension revalved instead.

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