Racing Fuel

[bone7615]

Can you run the high octane racing fuel in a 1996 Kdx.

[royadams]

Shure, but why bother.

[bone7615]

What are the pros and cons to it.

[6 Riders]

Pros, it burns clean,
Cons, it costs way to much money, it burns hot, it costs way to much money.....race gas is a waist in a kdx.

[bone7615]

Rite on well played.

[IDRIDR]

I agree that burning higher octane than needed is usually much more expensive and therefore efficiently lightens the wallet.

But why would it burn hot?
Honest question.

http://www.hioctanefuel.com/faq.html

.

[adam728]

But why would it burn hot?
Honest question.

http://www.hioctanefuel.com/faq.html

.

It wouldn't burn hotter, in general. Fuels are an extremely complex subject, and burn rate, engine temps, charge cooling, throttle response, etc etc all depend on fuel blend, not octane. You can have two 100 octane race fuels with dramatically different characteristics.

[BlackMist]

maybe if you were to bump the ignition timing way up you could utilize a little more from it

on a side note, it would smell amazing!!

[bone7615]

I do love that smell.

[royadams]

Unless your going to cut the head for race fuel you wont see any gains. As for the smell, maxima 927 has a very simular smell.

[adam728]

Unless your going to cut the head for race fuel you wont see any gains. As for the smell, maxima 927 has a very simular smell.

Very true, a compression bump is most likely needed to take any real benefit.



Just throwing more timing at it doesn't do much unless you were limited by detonation previously. Many engines are setup running near MBT, or maximum brake-torque timing (or minimum best timing, or 13 other names it's often called). Advancing the timing further simply decreases power. If an engine cannot reach MBT because of detonation on a certian fuel, then yes, running better fuel and throwing more timing at it can help. The KDX is a very mildly tuned bike and simply doesn't require "race" fuel.

[bone7615]

I can see a major difference when I run premium then regular. I put regular in my bike last summer and it seemed way under power.

[adam728]

Placebo, unless it was knocking or some seriously bad fuel.

[Bitteeinit]

So regular or premium shouldn't make a difference? I've used both and have never noticed a big difference, but I tend to go for premium.

[Julien D]

Regular is not a good match. The compression warrants premium, but anything more would be overkill.

[fuzzy]

The lowest octane to avoid pre-ignition will make the most power for whatever static compression ratio. It will inherently run richer and therefore feel even doggier just by pouring it in the tank. Race gas will however provide better throttle response, and possibly some more off idle pull. Most who play with gas will just run a smaller percentage of it cut with pump, or use tolulene to get the same grunt. Be careful however, you must tune to take advangtage (lean the mixture), and don't go back to straight pump after the fact without fattening the jetting back up. In summary, Unless you're in the practice of anally tuning your bike to stoichometric A/F I wouldn't bother with it!!

[Julien D]

^ What he said :-)

[adam728]

Needing to lean the jetting when going to race gas is a very general recommendation. There are a lot of oxygenated race fuels, as well as plenty with specific gravity less than pump gas.

It all comes down to testing with what you are running and tweaking as needed.