XH Motorcycles Forum
Motorcycle Resource Forums => Technical Resource Discussion => Topic started by: 2CoolWheels on December 15, 2013, 06:24:44 PM
-
Greetings EH Xperts,
I've noticed that 901 has been pinging lately, most noticeably when riding near sea level on hard throttle. At higher elevations where the air is less dense, it is significantly reduced, even on hard throttle. I always use the highest available octane, which in California is 91. It has the Super X Tune, and all the recommended updates. I don't see a baro sensor in the schematic, how does the ECU determine air density? Any suggestions?
Thanks,
Mike
-
Wow Mike....
My thoughts with no proof are 91 is on the lite side... but will work. I know from experience that 525, pings terrible on 89... I was desperate that day.
Try an octtane boost?
-
Have you tried buying fuel from a different station or supplier? Just a thought.
Dennis
-
I usually purchase Shell, Mobil or Chevron gasoline. They tend to use less ethanol than some other brands. It seems like altitude should be compensated for, and pinging would be the same regardless of altitude. What ads to the puzzle is that 741 doesn't have the same problem. Not sure what tune is in 741, probably a Bobby Baldwin (X-man) tune. The next time I run to the coast, I'll definitely bring a little octane booster.
-
Just for comparison, I'm in the Chicago metro area and even our 'good' gas at Amoco or Mobil has 10% ethanol and God only knows what else in it. I've been running the mid grade stuff, round 89, and no pinging or problems. Yet.
-
The ECU has an integrated Barometric Pressure Sensor Circuit which is read by the SuperXtune. The reading is displayed on the Real Time Monitor. If it is out-of-range check that the vent tube is not clogged. The tube looks like a black rubber elbow exiting the lower right corner of the ECU. It is removable for cleaning if necessary. (Don't blow air into the ECU)
The ECU also uses input from the crankshaft position sensor and the road speed sensor to control fuel injection and ignition timing. Both sensors generate voltage pulses that the ECU uses to optimize performance.
Are there any other symptoms, Like speedometer wobble, or drop in power at certain altitudes?
Jamie
-
Jamie,
Thanks for the input....no, I don't notice any speedo issues or lack of power (other than giving it less throttle to avoid the pinging). I'll check the vent on the ECU you mentioned....good to know.
Mike
-
91 is pretty thin fuel... This is my opinion and I have no facts or proof to back it up.. But.. Go down to your local speed shop... The one that carries race fuel... Get a 5 gallon jug of Sunoco Unleaded 100 Octane and mix a gallon or so with your 91... Might get rid of the pinging some...
http://www.racegas.com/
Click on the map and find a retailer near you...
Jumper
;)