octane fuel?

[200xkwit]

ive been told to use a higher octane feul in my 200x becuase of the mods I have to it: wesico high compression pistion on .20 bore,uni air filter with holes in air box,cobra pipe, 105 and 38 jet size... now would I need to run higher octane fuel? well put it this way would it runner better? leaner/richer?

[MTS]

well for one, what octane fule are you running in it alredy, also have you noticed any popping noised or knocks from it ?

[Studytime]

Fuel can only take so much heat from compression (in you have an increased compression ratio, your compression takes place faster) without preignition. The preignition will cause your engine to literally melt if severe enough.

Preignition if battled by "anti-knock" agents in your fuel. That's what octane is. You can run as low a grade as possible without knocking. So, if you run a "more expensive" gas does it give you more power? No. If you only require 87 octane, then 92 will do nothing for you. It is in no means a "treat" for your bike. However your bike with increased compression will more than likely require premium pump gas depending on your final dynamic compression ratio.

Studytime

[200xkwit]

yea actually now that I think about it when I acccelerate and get on the throttle it makes a ticking noise. more or not when i get on the throttle hard. Im running 92 right now

[MTS]

what high compresion piston are you running...10:25:1???

[Studytime]

A "ticking noise"? Like a slightly louder than normal sewing machine?

Studytime

[200xkwit]

yea 10:25:1 I dont know ive never heard a sewing machine... but I can hear it threw my helmet when im riding ( when i concintrate on the sound)

[smokinp]

the 10.25:1 compression piston runs fine on pump gas,I would just run supreme gas in it that would be enough....

[OldSchoolin86]

At 10.25:1 you shouldn't need anymore than 90. It's possible your hearing the valves.

[PlatinumDogg]

Yeah i think i can relate to that. I run 91 octane and it makes a knocking sound under hard excel or when im going throught deep mud it makes a knocking sound. Bascially when i really work the engine. IT was recently rebuilt with about 20 hours maybe on the rebuild. Also im runnign that weisco 10.5:1

[HaggLE]

We can get 98 from the pump here in australia! thats all i run in my trike and car. Its more expensive but works out in the end in the car because the "mileage" is better. Regular is 91 in australia.

This noise your talking about, does it only happen under load or when you are labouring? If so then higher octane will help the situation and/or try retarding the ignition timing a little or in other words make it spark later. Turn the CDI pickup the direction of the motor to achieve this.