what octane fuel

[tman12345]

what octane fuel do you run?

93 octane here nothing less

[tman12345]

Originally posted by FoxHondaRider
93 octane here nothing less
yea thats what i run, i think the manual says 92 or better, but there is only 93 around at my local gas stations.

[trx400EXtreme]

yep its pump gas for me.

[81 clark racing]

93 mixedd with cam2. ( 110 octane) she runs amazing

my brothers 400ex was in the process of a rebuild so my friend bought a little phoenix 200cc for my brother to ride. now imagine someone 6'3" on a phoenix. Now my friend used to use race gas 107octane mixed with 93octane(used 2 separate tnaks 1 for 107, 1for 93) in his 440 but his gas can with 107octane is the same exact gas can I have that i always have 93octane in. Little loe Phoenix was low on gas before our ride out so my brother just pics up the can and fills it, while almost full he ask why is this gas blue? we respond with a no you didnt just fill up this with straight race gas on a stock 200c quad! well he did and the whole night no lie it shot out a blue flame about a foot long! funniest thing ever. just had to tell a funny story about different octanes since we were on the gas subject.

[boosted3g]

50% 93 octane pump and 50% E85 105 octane

[exrider49]

VP c12

[tanner 222]

i've asked this same question before and lots of people have said if you run 12:1 compression or lower you shouldnt run anymore than 92 octane (which is what we have in canada but 93 would be the same). if you are running 13:1 or more compression than use 50/50 race fuel and 93 pump gas for 13:1 and any bigger then run straight race gas. thats what i got for a response.

[GPracer2500]

Originally posted by tanner 222
i've asked this same question before and lots of people have said if you run 12:1 compression or lower you shouldnt run anymore than 92 octane (which is what we have in canada but 93 would be the same). if you are running 13:1 or more compression than use 50/50 race fuel and 93 pump gas for 13:1 and any bigger then run straight race gas. thats what i got for a response.

It's never that cut and dry. Maybe that would be a mostly fair statement if you're talking about one particular engine. But those guidelines would NOT work for a 400EX. Barring unusual circumstances, a 400EX with a 12:1 static comp piston is likely to knock dangerously on premium pump. It would be a different situation on some other (liquid cooled) engine.

There's a lot more that goes into an engine's minimum required octane rating than just the static compression specification of the piston.

[tanner 222]

Originally posted by GPracer2500
It's never that cut and dry. Maybe that would be a mostly fair statement if you're talking about one particular engine. But those guidelines would NOT work for a 400EX. Barring unusual circumstances, a 400EX with a 12:1 static comp piston is likely to knock dangerously on premium pump. It would be a different situation on some other (liquid cooled) engine.

There's a lot more that goes into an engine's minimum required octane rating than just the static compression specification of the piston.

well when i asked the question thats what i got for an answer. i'm not saying this from experience. what you said would make more sense. all motors are different. the guy who give me the answer was riding a 450r so maybe it is for liquid cooled motors.

as long as your run at least 92 when stock your fine. I ran lower once on accident and it bogged down and ran like crap.