S4R sputtering

[Fitzy]

Hey guys i looked a little bit on here for a fuel thread but im not seeing anything concrete on the subject, so heres my issue i bought my s4r in europe with dp ecu and airbox top,, 3500 miles on it had fresh timing belt and had its first valve check at 3000 miles. I ran nothing but 102 octane in it (you can buy it at the pump in germany) so i just moved back to the states and my bike just hit 6000 miles and shes sputtering i little bit every now and then and a bit harder starting i think its because of the 91 octane ive been feeding it but im wondering if its time to have the valves checked again. Any help would be great 

[Heath]

Remember Euro Octane ratings are higher then the US. A 102 Euro rating is about 95 US. 

[Fitzy]

thanks your right its still a better fuel than i get now hands down and i really think its the fuel but im very new to these crazy valve springless awesome motors

[Raux]

is it a custom tune on the ecu?


is the closed loop gone?

if so, are there major elevation differences between locations?

[Fitzy]

Well not sure about the tune i was told its ducati performance but its also not the stock ecu cuz i have it as well its only about 500 feet higher elevation so im gonna rule that out as far as the closed loop im not sure

[Thermite]

 More detail on the sputtering please:

Hot/Cold. Idle/WOT. Accel/Decel. Alone/When everybody's watching.

Well, never mind the last one (we all know the answer) but you get the idea.  Under what condition is it the worst?

Also what's the status of routine maintenance (air filter, fuel filter, plugs).

[Mr.Purple]

AFAIK the german 100 and 98 RON octane fuel is without ethanol. Does the fuel you use in the US contain ethanol? Could the ethanol affect the engine?

I run 95 RON on my non-testa S4R with DP ecu, runs clean and starts at once, even in cold weather.

[Fitzy]

It happens when i let off and then get right back on it  kinda sounds like a backfire in the intake its weird and like i said before its not easy to start compared to how it normally was. As far as maintenance is concerned oil needs to be changed will do it this weekend and i haven't ever needed to pull a spark plug yet but i will pull them this weekend too the thing just hit 6000 miles so i don't really know whats due but i know the timing belt was done at 3000 miles and Norways4r the fuel has 10% ethanol 

[Howie]

AFAIK the german 100 and 98 RON octane fuel is without ethanol. Does the fuel you use in the US contain ethanol? Could the ethanol affect the engine?

I run 95 RON on my non-testa S4R with DP ecu, runs clean and starts at once, even in cold weather.

Fuel in most of the USA contains ethanol, some rural areas still offer real, proper gasoline.  10% ethanol can hurt rubber fuel parts and does result in a loss of power and fuel economy.  We won't even talk about plastic fuel tanks. 

[Ak1nza]

Have you tried checking the fuel filter?

[Mr.Purple]

If the DP map is made for german 100ron fuel, closed loop. Wouldn't that cause problems with the lower octane fuel containing ethanol?

[Howie]

If the DP map is made for german 100ron fuel, closed loop. Wouldn't that cause problems with the lower octane fuel containing ethanol?

In the US the octane rating on the pump is RON+MON/2, known as AKI.  Arithmetic says, since it is an average, if RON was 100 and MON was 85, 93 AKI would be perfect plus a little bit.  Problem is it is not, in reality, an arithmetic average.  The testing methods use different variables.  I can't say for newer Ducs, but most older Ducs, unless compression is raised, run fine on 87 AKII

[Fitzy]

Howie you seem like you got these things figured out when valves need to be adjusted what are symptoms that you would see? the bike seems to run the same on 91 as is does on 87 so im guessing its just time for a valve adjustment nothing more

[Howie]

The only sure fire check for seeing if you need a valve adjustment is to actually check clearance.  In your case, assuming the valve adjustment was done correctly not too long ago, first I would look at the spark plugs.