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KDX racing fuel

Posted: 05:35 am Aug 31 2006
by motofox2006
Hey anyone here know if i can run my bike on racing fuel.

I have a 1991 kdx200 and usually run it on 91 octane gas

If i cant run it on racing fuel dos anyone know what gas i should be usign

Thanx guys

Posted: 07:07 am Aug 31 2006
by KDXer
I use 98 octane premium unleaded petrol. I reckon you would need head work to compliment race gas. If you go with race gas send your head (and carby while your at it) to Ron at http://www.rb-designs.com to get the ol girl really flying but be sure to tell him you want it for race gas and what grade of race gas and what elevation and what humidity and....

Posted: 08:42 am Aug 31 2006
by fuzzy
Yeah, no need for it unless your engine has been modded to utilize it. It will give you a bit better throttle response, and you can jet closer to stoichiometric (sp) tune as the fuel is much more consistent than pump gas. Gotta be real keen on jetting to even worry about it.

stoichiometric (sp) tune - right on the gnat's a$$ of bring too lean. The point of greatest power output.

Posted: 12:22 pm Aug 31 2006
by dave04kdx
Do a search on "Toluene". We had some very good info from Ron a year or so ago about using toluene mixed with pump gas. I am still using it and my bike is running great. Plently of bottom end and no more pinging.

Posted: 02:19 pm Aug 31 2006
by motofox2006
>|<>QBB<
KAY DEE EXER wrote:I use 98 octane premium unleaded petrol. I reckon you would need head work to compliment race gas. If you go with race gas send your head (and carby while your at it) to Ron at http://www.rb-designs.com to get the ol girl really flying but be sure to tell him you want it for race gas and what grade of race gas and what elevation and what humidity and....
Yeah not a bad idea but i live in New Zealand which is long was away from USA and im 15 and cant aford shipping back and forth let alone the price they charge for head and carb mods.

Posted: 02:26 pm Aug 31 2006
by motofox2006
I can get race gas at my local petrol station and its not that expensive,
do you think it will work at all without head mods etc I was thinking of trying some as the last guy who had the bike, said he used it every now and then.

Could i go with a 50/50 98 octane and racing fuel mix.

And also it wont blow my engine by using it will it.

Posted: 08:51 am Sep 01 2006
by fuzzy
No, you won't hurt it but you may actually make less power if you don't do certain things to utilize it...

Posted: 04:44 pm Sep 01 2006
by motofox2006
What do you mean bu utilize it and whats the chances of it giving me less power as the guy i bought it off said every now and then he used racing fuel or (ave gas) to give it a bit more go. he may of been talking a load of crap however.

Posted: 08:23 pm Sep 01 2006
by fuzzy
You will get the slightly better respose as mentioned, but on a dyno you may actually see a loss in power. If your short on cash, forget about race gas and worry about other stuff including saving your money for that stuff... :wink: If the bike doesn't ping when you rev it to the moon, then you don't have an octane shortage.

Posted: 09:21 pm Sep 01 2006
by AZRickD
RB carb and head mod (for pump gas)

I recently experimented with adding toluene at 5, 10 and 20% to my normally 91 octane pre-mix.

It ran fine on all of them (with a clean, "just brushed freshness"), but I'm unwilling at this time to spend the extra dough for this.

Rick