Race Gas

[JUGGS]

Ok i have a 2002 banshee with these mods. cool head with 21cc domes, v-force 2 reeds, weisco pro lites stock bore, timing is advanced 4 degrees and fmf pipes, I am at 500 feet above sea level.. My question is do i need to run more than 93 octane pump gas i just got to ride it today and i'm hearing a slite nock or pinging sound other than the pipes.. I can hear it at idle and it gets louder when its under a load... Am i getin detination from lack of octane or what am i missing?? Thanks Matt

[jbooker82]

Run 100% race gas. If the sound you are hearing goes away then try 50/50. Still no strange sound try 25/75. If the sound comes back then you know you will need to a little more race gas with regular. Start at 100% and ween it down until you her the pinging come back and then up the % a little more until it goes away.

 

Lean jetting can aslo make pining worse. Try backing your timing off if you dont want to run race fuel.

[CRAZY-SHEE!]

idk.. 21cc domes shouldnt need race gas.. do a compression test..

[Washburn]

idk.. 21cc domes shouldnt need race gas.. do a compression test..

 

 

True but he also has his timing advanced and you can never really tell with that. plus the 500ft asl is bumping it. Definatly do a compression test.

 

Take jbookers advice. You can also try going to a local airport and buying 100AV fuel. It costs like 4-4.75 a gallon just run that straight.

 

What ratio are you mixing your fuel at? Just curious

[06BaNsHeE]

Do a compression test.If your at 155-170 Run Straight av gas or 50/50 race with 93 pump.Anything over 170 I would run straight race gas

[06BaNsHeE]

I curenntly pay 3.50$ per gallon for av gas

[jbooker82]

I curenntly pay 3.50$ per gallon for av gas

 

I get citgo 110 for $4

[bigboybanshee]

Pinging is definitely a sign of detonation, but like said before, with 21cc domes you should be about 150psi on a fresh top end. I ran 21cc's at the same elevation, similar mods and +4 timing with 93 octane; no problems. Now I run 160psi with +4 timing and am still on pump, no detonation, plugs look good, 400ft above sea level.

 

I would listen closer to the noise, see if it's definitely coming from the cylinders. Could it be a water impellar making that noise? Maybe your kickstarter is wearing out? Just some ideas, could be a loose bolt somewhere for all you know. Always check the simplest things first. I had a weird rattling noise come from my blue bike that had me worried...come to find out I didn't tighten my clutch cover insert down and it was making all kinds of racket, lol

[SoCalinIt]

I get citgo 110 for $4

 

DAMN! Must be nice... I'm paying $9 for TRICK 110 here in SoCal.

[06BaNsHeE]

8$ a gallon for VP C-12

[blowit]

Ok i have a 2002 banshee with these mods. cool head with 21cc domes, v-force 2 reeds, weisco pro lites stock bore, timing is advanced 4 degrees and fmf pipes, I am at 500 feet above sea level.. My question is do i need to run more than 93 octane pump gas i just got to ride it today and i'm hearing a slite nock or pinging sound other than the pipes.. I can hear it at idle and it gets louder when its under a load... Am i getin detination from lack of octane or what am i missing?? Thanks Matt

 

 

You should not be into race fuel territory with that combination. I too would want to check jetting and static compression. Lean motors will detonate. If possible and if you have enough time on the plugs, post a closeup of your plugs. A sure sign of detonation is fine metallic specs on the plug which it metal transfer from the piston. I am not convinced that you are detonating just yet. It is a good test though to run a small amount of race fuel just to test for a sound change in the motor. Obvious detonation is hard to miss. Let is know.

 

Brandon

[CRAZY-SHEE!]

DAMN! Must be nice... I'm paying $9 for TRICK 110 here in SoCal.

 

 

u made my wallet cry :sad:

[RoostRocket]

8$ a gallon for VP C-12

7.50 for trick 114