Page 1 of 1
RB head and gas..
Posted: 12:48 pm May 21 2014
by frenche200
Hello!
I bought there a few times a RB Head (not for competition gas) at a member of the forum (transaction very pleasant ) I have not still installed but I have a question:
Here in France we have different fuel:
-SP95 (95 RON, MON 85); : Unleaded petrol (lead is replaced by potassium), 95 octane (it seems me it is 5% ethanol)
-SP98 (98 RON, MON 87) unleaded fuel ( lead is replaced by potassium), octane 98
-SP95-E10 (95 RON, MON 85). : Unleaded 95 octane, 10% bioethanol
Currently, my bike ride to SP95 or SP 98, and I wonder if the fuel is compatible with this new head , and which is better?
Thank you :D
Re: RB head and gas..
Posted: 02:25 pm May 21 2014
by 6 Riders
SP 98, everytime, no matter what head you are running.
Re: RB head and gas..
Posted: 03:09 pm May 21 2014
by SS109
6 Riders wrote:SP 98, everytime, no matter what head you are running.
I agree.
RB head and gas..
Posted: 03:23 pm May 21 2014
by frenche200
thank you guys! particular reason to prefer the SP98?
Re: RB head and gas..
Posted: 04:45 pm May 21 2014
by bufftester
Highest octane and no ethanol is my guess. Supposedly Ethanol in fuel can be linked to reduced life in seals (specifically crank), although most seals are viton and not harmed by ethanol. Kind of the same argument as synthetic vs non-synthetic oil...
Re: RB head and gas..
Posted: 06:09 pm May 21 2014
by C George
6 Riders wrote:SP 98, everytime, no matter what head you are running.
+1 ,,, mostly because it's got no ethanol ,, terrible stuff for 2 strokes
Re: RB head and gas..
Posted: 07:42 pm May 21 2014
by KDXGarage
In the USA, we have RON+MON/2, so SP98 is 92.5 in the USA.
RB head and gas..
Posted: 06:13 am May 22 2014
by SS109
I run the highest octane I can get (91 around here) because my bike just flat out runs better on it.
RB head and gas..
Posted: 10:02 am May 22 2014
by scheckaet
SS109 wrote:I run the highest octane I can get (91 around here) because my bike just flat out runs better on it.
+1 on that.
RB head and gas..
Posted: 06:46 am May 23 2014
by frenche200
thank you for all your answers! last question: do you think I need to change jet to mount the new head?
Re: RB head and gas..
Posted: 07:09 am May 23 2014
by diymirage
yes, any change to engine or running conditions you should rejet
if you change what gas you use, rejet
if you change what oil you use, rejet
if you change your gear ratio, don't rejet, that has nothing to do with the engine
but if you change compression and squish band, rejet
RB head and gas..
Posted: 09:18 am May 23 2014
by scheckaet
check my sig for jetting how to. nothing expensive or complicated, just time and patience.
RB head and gas..
Posted: 06:01 pm May 23 2014
by frenche200
thank you Diymirage and Scheckaet! I thought about changing my pipe for an fmf so I'll put everything at the same time, to make adjustments only once .. thank you for everything!
