Race Gas or Super
Posted February 21, 2001 - 06:44 AM
Posted February 21, 2001 - 10:02 PM
Posted February 22, 2001 - 02:51 AM
Posted February 22, 2001 - 04:31 AM
Posted February 22, 2001 - 08:15 PM
Posted February 24, 2001 - 09:14 PM
Posted February 25, 2001 - 04:54 AM
Posted March 06, 2001 - 12:59 AM
My experience with using race gas has been good and I have not experienced any of the problems that the magazines have mentioned. When I first got my 98 400, I spoke to Larry Roeseler about the fuel issues and he was very clear in describing the octane and leaded fuel needs of a high compression engine. Jetting changes may be necessary too.
When $$$$ are short I will mix 50/50 but I will never use straight pump gas in my bikes.
I guess I am lucky to have a mentor like Larry Roeseler to guide me.
Posted March 06, 2001 - 03:53 AM
Posted March 07, 2001 - 09:11 PM
Posted March 08, 2001 - 12:55 AM
The most usual race gas is made out of acetylate.
This is a strickly chemical mixture that contains approx. 08-1,2 % Oxygene.
This is cleaner and containd clean chemical additives that will keep Your valves, piston a.s.o lubed allright.
The only thing is: If You run it at a low comp. ratio, it will give You one effect only: The price and nothing else.
In a high comp. engine it will give You a better mid range punch and a smother powerband. One throwback is that it will be more sensetive of jetting.
Hope this helps!! Numpsy
Posted March 08, 2001 - 05:04 AM
MOST race gas is not even designed for 13,000 rpm. i talked at length with a Howell Fuel distrubitor and he said they had NOTHING to offer me. my motor spins way to FAST for their race gas. now, think how bad pump fuel must be. he said their best stuff that is designed for 9800rpm is no good.
now, i live relatively close to the VP world wide distillery plant. i KNOW of 2 guys that actually work at VP. one of them was in my class the last 2 years. i was in the first VP GP race on the new VP MX track there in Floresville,TX.
in order of best fuels to run for a 426 or 250F:
VP Red, VP103, C-12, C-14 and C-18.
that is for NON-oxygenated fuels with C-18 being the best. MR2, MR3 and MR4 certainly have their place, but are VERY expensive to run. all are 2.55% oxygenated. MR2 is the fuel that all of the SuperCross and MotoCross pro's run.
MikeOK, dude, lay off the crack pipe. race gas is NOT gonna hurt that carb. i know several guys that have run NOTHING BUT race gas in their '98yz400's since day one. they still run fine. my 250F has had race gas in the tank since the day i first fired it up.
what most of you are failing to understand is that the 250F/400/426 motors are RACING engines. they are not designed for taking grandma to the corner for a loaf of bread and a quart of milk. the factory specified IDLE of the 250F is 1700-1900 rpm. that is IDLE!!! how many of you notice the rpm of your car/truck cruising down the hiway at 65mph? yeah, now realize that these race bikes idle at almost that rpm. grab a clue!
[This message has been edited by SUnruh (edited 03-08-2001).]
Posted March 08, 2001 - 07:03 AM
Originally posted by SUnruh:
…think how bad pump fuel must be.
So bad that it is recommended in the manual, while race gas is not. According to Yamaha, (the company that manufactured the bike) the YZF is designed to run on premium unleaded. They obviously need to grab a clue!
They are not designed for taking grandma to the corner for a loaf of bread and a quart of milk.
That may be true, but don’t tell my grandma.
Posted March 08, 2001 - 04:20 PM
How many bikes would Yamaha sell if they told you that you have to run race gas for the bike to perform properly? Probably not to many. That is also why the two strokes are jetted fat from the factory so you don't go out and sieze it right away.
I have run only race gas in my 400 and my 01 426 since they were new. I have NEVER had a problem with the carbs becoming gumed up. I have over three years of riding, practice and racing on my 98 400 and my carb has never been apart except for jetting changes.
Larry Roeseler tells me that I would have never got that much longevity out of my 400 without using race gas. This is because of the consistancy of the fuel quality and the higher octain. He said even though you may not hear it detonate on pump gas, the running temperature is substantially higher. Higher temps result in faster oil breakdown, increased heat related issues within the engine and the list goes on.
I know race gas is expensive but you get what you pay for.
Posted March 08, 2001 - 10:33 PM
Posted March 09, 2001 - 07:44 AM
It's economics, pure and simple. The Yamaha manual says to use 95. Oh, I can't buy it but I can buy the Yamaha "octane booster" and put more money in the company coffers. It's the same as the oil. Yamaha does not have an oil well in some secret location pumping out oil that will only work in there engines.
If they can keep you confused just long enough for you to buy their overpriced "yamalube" products, cha-ching........$$$$$$$.
Posted March 09, 2001 - 08:17 AM
I forget which, but one is generally higher than the other. The point is that an avg. of 92 should be equivalent to the recommended 95. Actually, the REAL point is that if the motor ain’t knockin’ then higher octane is not warranted. Lots of factors affect how much octane a motor needs so individual experience matters more than what is recommended. YZFs at sea level may well suffer preignition on premium unleaded in certain conditions, but here in the high dez my 13.5:1 YZF does not.
I’m sure my bike would run better and last longer (unless the tranny goes again, will race gas prevent that?) on race gas, so it is probably better than spending money on carbon fiber and Ti, but it ain’t gonna win any races for you.
My bike is plenty fast on pump gas, thank you, and I have no reasonably convenient or reliable access to the proper race gas anyway. Running the wrong race gas may actually cost HP vs. pump gas. It sounds like SUnruh knows what is what so if you want race gas buy the stuff he recommends.
I did not know that Yamaha made octane booster and I did not see where the manual recommended it (like it does the Yamalube engine oil, Yamabond etc.), otherwise I might agree with you Mojo. What I don’t get is why they say that race gas will ruin the carb, obviously that is not true, hell I bet their race bikes all use it.
Posted March 09, 2001 - 10:48 PM
[This message has been edited by dirtdad (edited 03-09-2001).]
Posted March 09, 2001 - 08:26 PM
Actually Yamaha does make the Octane boost. I read the maunual and it didn't recommend the boost..but...if all that people are seeing is 92 as a high, they'll call their dealer and he could help out with an overpriced additive. Your right, it didn't say to use their product in the manual.
I concur with you wholeheartedly on the fact the bike is plenty fast on good old super at the pump.
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