High octane fuel talk and information

[Jeremy]

The post in the wanted section made me wonder what everyone is running and why.

So... what fuel are you running? Why that fuel? What compression ratio? What other fuels have you tried?



When I switched to high compression in my TRX I started running Sunoco 110 because it was easily accessible at the Loves station off of I-10. I ran that for quite a while with CP, JE (Sparks) and Wiseco (Baldwin) pistons and was completely happy. Once I started having Racers Edge do my motor work they suggested running VP fuels but I continued with Sunoco 110. After running my build for a while I sent the head back to them and they commented on the very high amount of deposits that the fuel was leaving on the back side of the valves and once again suggested switching to VP fuels. So after that I went to VP 110 and never went back. The VP fuel seemed to run stronger, slightly lower temps, and kept the head cleaner.

So thats my input on the subject

[06YFZ45racer]

I run the highest octane i can get from the mexican gas station on my way out to the track!

[Dillon 17]

Ive ran vp110 and sunoco 110 and I personaly couldnt tell a difference. Ive just stuck with the sunoco 110 because its cheaper and easy to get at any Loves truck stop. I've never had a problem with it.

[panici33]

I am a little leery about using race fuel from a gas station; I don't know why, call me old fashion. However, because of my current circumstances (moving, availability, etc etc) and I am only needing a couple of gallons, and it is easily accessible, I will be going to Westy Motorsports to get a couple of gallons of Sunuco 110; I will let everyone know if I feel a difference but probably not. I have 13.5 compression JE piston that has only seen VP U4.2. I have heard a lot of great things about this fuel and have no problems thus far. I will be doing a tear down probably after the move to take a look of the insides and can post afterward.

Once back in the Midwest I will go back to Klotz because of the cheaper price, accessibility and performance. Klotz isn't very accessible here in the West but it is a very good fuel as well (smells really good too ) They have 100, 108, 110 and many other octanes. I ran their 100 octane in my stock compression 04 YFZ450. Felt a considerable difference. I will use Klotz110 with the Suzook.

[code918]

Mods:
Port & polished head
Webb 963 Cams
Full exhaust
Carb work
14:1 CP piston
CDI box

Was running VP U4.2 for awhile. Ran really strong and smelled good. I did notice that the valves and carb slide started to get a little gummed up if any of the gas was allowed to sit for a few days or more. Almost had to flush the entire system to clean it up once in awhile. U4.2 is leaded and oxygenated. The leaded I liked, but after running the stuff for awhile, decided to try something that was NOT oxygenated. Switched to VP110 and couldn't be happier.

My vote for the "jet" fuel is VP110.

[Jeremy]

Any reason you ran the oxygenated fuel? Any gumming issues? Did you drain the carb after every ride?

Surprised you felt anything by putting 100 octane in a stock compression bike. Might have just been in your head?

[panici33]

Surprised you felt anything by putting 100 octane in a stock compression bike. Might have just been in your head?

Might have been the fumes; it smells soooo good.

Should have said saw a difference, mainly talking about the cleanliness of the head and not so much the performance. Pump fuel leaves high amounts of deposits.

There is a good article on race fuels in one of the Quad Magazines I used to have (wife threw them all away). Someone should find it and post. Talked about differences between leaded, unleaded, oxygenated, etc.

[Effinbees77]

When it was available I would run VP MR9. Flat out made the most peak HP out of the other accesible fuels. It was like 87 Octaine and was highly oxygenated. You can check their site if you want details. I switched to MRX01 since MR9 is no longer available. MRX01 does make slightly less HP but it's the kind of HP loss that you can't feel. Both these fuels are a pain in the butt though. After running - Drain the tank & carb and then run regular race fuel through to make sure there's none remaining. I run the MRX01 at Supermoto & TT races only where you need every ounce of HP. For MX, I just run VPC12. And yes, it's a night & day difference between running VP C12 & MRX01. It's also $100.00 for 5 gal.

[Jeremy]

How far off is the jetting between C12 and MRX01 for you Kenny? The MRX01 probably requires quite a bit larger jet, right?

[Effinbees77]

Jetting? Me? Pshhhhheeeeeeit. I'll change a jet when one of them wears out :-)! Runs great on both! If I remember, there is a slight jetting change between the two. Basically, in my Lame-Mans terms, I'm jetted right in the middle. Bobby's too. They run great on both fuels.
Also, compression on my motors ranges from 14:1 to close to 15:1 and MR9 was 87 octane, MRX01 I believe is 89 octane.