What fuel?

[SMOKEU]

What octane fuel do you guys use in your 250s?

[Buckets4Me]

What octane fuel do you guys use in your 250s?

91 for my 1990 zxr250

[psycho22]

I always used 95 or 98 in my old Hyo and SR250

[qwertydog]

Same as the year of me bike (manufacturers specs )

[Gibbo89]

always 95 or 98. what do you use smoke?

[EJK]

I put diesel.

[davebullet]

91 in the VTR250 (all it requires according to the manual). Runs fine and we get 30km/litre.

[Lurch]

It's hard to find concensus on this but I doubt that many stock 250's would run better on 95/98 than they do on 91. Higher octane fuels do not automatically give an engine more power, they actually just burn longer and later in the compression cycle which may not suit many smaller capacity engines.

Also higher octane fuels tend to include more additives and cleaners which most of the time you are better off without and especially if your engine isn't completely combusting the fuel due to it not being tuned for it.

Partial reference:
http://homepages.slingshot.co.nz/~sh...ml#Question_18

[SMOKEU]

always 95 or 98. what do you use smoke?

98. I've recently started to use 91 to see if it makes any difference, but it doesn't seem to. I hope it won't detonate on 91.

[Spuds1234]

Check your manual out to see what your compression ratio is and then base your fuel purchases off that.

Easy.

[SMOKEU]

Check your manual out to see what your compression ratio is and then base your fuel purchases off that.

Easy.

11:1, I don't have a manual for it.

[GOONR]

91 in the Bandit, it doesn't like anything else.

[aprilia_RS250]

It says nothing below 95 on mine... That's all. I assume I could chuck av gas in there?

[SMOKEU]

I checked the workshop manual for my bike, and the the fuel type just says "Petrol". I never would have guessed...

[neels]

GSXR250 manual specifies 90 or greater, comp ratio (once upon a time was) 12.5:1