octane

[bigb9582]

will running strait 100 octane race gas in a 250sx hurt it?
i know running higher octane in a stock motor is not supposed to do any thing. BUT right now i have a tank of gas that is half 89 oct. and half 100 oct. and it seems to be running a lot stronger than before.
what i did was i had a full tank of 89, than i ran half of it down and fill back up with 100 and shook the trike to mix it well. i ran it for a while and it ran normal. then after 15 mins or so the trike seemed like it was pulling alot stronger up hills and accelerating alot faster than normal. i let my buddy ride it and he said the same thing that it felt a lot stronger than before.
do * think that its our imaginations and that we think it did something? or did it really improve the power?
like i said before i know higher octane is not supposed to do anything for a stock motor but this is wierd.

[Yamahauler]

i would say it is your imagination, but you never know. high octane gas is only usful for high compression motors because it burns slower and keeps it cooler. and a lower compression motor wont be able to burn that gas as good, which would actually decrease your performance.
but if it runs alright I wouldnt worry about dumping it. But I would just use regular next time you fill up.

[shudup]

makes no diff on stock motor wont hurt it

[Macs]

the higher octane will not hurt the motor at all, but it will change the performance over the 89 octane. with stock compression on a 200x you should gain power till about 94/ 95 octane then the rest is just a waist.

[BIGCRIP28]

it wont hurt anything, but its more than you need.

[Mike_Ham_250R]

Yeah i remember i beat the $#!7 outta my TRX250 recon when i was young and it started not to run as stong, so i bought 93 once and i noticed a nice improvement.

[OldSchoolin86]

Octain will not gain you performance period, not hp or cooling. The only thing it will do for you is prevent pre-detonation which is caused by HEAT not compression (compression causes heat). Some of your better high octain fuels are oxygenated and that will help but NOT octain alone.

[Pigga]

just run 91 race fuel is a waste of money. you only need race fuel in 12:1+ motors

[MTS]

Not to mention, race gas is HARD on a motor, and with a stock motor with what dose it have 8:1? all its gona do is retard proformance becuse it cant burn the fuel as nice.

[pjk15cartoon]

save your money. I agree with you guys.

[Tri-ZNate]

I tried running 93 octane in my SX and all it did was spit gas out when I reved it high since it couldnt burnt it all. I didnt seem to make a diff but if you running a hotter spark plug than reccmended maybe you can burn all the gas and make the higher octane do something for the SX.


And I think the stock compression on an sx is 9:1

[bigb9582]

i know i got a champion powersport plug in it. they didnt have one for the sx, so i got one that fit a 200s. which had a lower number. but it works good.

[Hornetpowerspor]

We have already had a thread on this subject. Higher octane will burn slower, thus making your motor run cooler. It is a waste in a stock motor with low compression, but will not hurt a thing. Heat causes detonation, if you hear pinging up your octane.

[bigb9582]

i was not rying to start another thread about that. i was mainly asking why my sx ran better with 100oct. and its still stock as far as i know. yesterday i put 89 back in and it doesnt pull as hard. i can feel a difference.

[slothminx]

if your timing was too far advanced you would feel a difference, as putting in the higher octane fuel would be correct for that timing setup. you could try retarding your timing a few degrees (having a timing light is useful) and see if that improves the performance at all.

will

[bigb9582]

thanx for the tip. i may try that in a few days to see if that helps.

[bigyellow4x4]

well race gas is not all the same as far as 93 to 100 you dont need the octane but some race gas (like trick fuel) uses alot more things in it than octane booster like taluline (sorry about spelling), and it carries more oxgen in it. and that is more and likily what you are getting the power from not the octane. Used trick 100 in a road bike (small like 350 cc with rider wieght of 245 pds) and got 1100 more rpms out of the old girl. thats my 2 cents