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