It was real cold this morning (for me anyway, about 4-7 degrees Celcius). My '94 m900 started fine and ran fine for half the 15 minute ride, but started backfiring, struggling at idle and generally running shitty after that. It was better once I was moving or revving high, but was still super rough and poppy. Any ideas?
edit. Oil temp only got up to 30-40 degrees C.
Quote from: Howley on June 30, 2008, 08:01:22 PM
It was real cold this morning (for me anyway, about 4-7 degrees Celcius). My '94 m900 started fine and ran fine for half the 15 minute ride, but started backfiring, struggling at idle and generally running shitty after that. It was better once I was moving or revving high, but was still super rough and poppy. Any ideas?
edit. Oil temp only got up to 30-40 degrees C.
Whats the humidity like there? Icing carbs maybe? (They "ice" at quite a bit warmer than freezing due to the cooling effect of evaporating the fuel.) Does yours have the tap to provide oil heating to the float bowls?
big
It doesn't have the carb warming thing. It's quite possible it was icing, I just checked the graphs and the air temp was around 2 degrees C.
It ran fine on the way home. I guess it was iced up.
I've experienced carburetor icing a few times on the 1997 M900 that I used to have. Stopping and idling for a few minutes usually fixed things by warming the carburetors back up. By "idling", I mean blipping the throttle or whatever else it took to keep the bike running. The temperature you've described is in the optimal range for carburetor icing, by the way.
I checked the weather for the second day it happened and it was 4 degrees C and 94% humidity.
I've never had a carbie Monster, but that seems like perfect conditions for icing.
I thought so too [laugh]
I had exact same problem this week. Temp about 3deg C and high humidity. Engine good for 7mins then progressively shit and eventually had to get bike home at 4000+ rpm while filtering and slipping clutch for 20 mins.
Found an oil diverter on my 97 M900 which diverts hot oil to carbs for such occasions. All carby riders make sure you use this device with cold riding if fitted. I will be in future. Knowing Ducati in 96/97 anything can be on your bike and not necessarily what the manual says.
I am attaching link for reading as this describes perfectly the symptoms. It is not a pretty experience when it happens.
http://faq.ninja250.org/wiki/What_is_carburetor_ice%3F
Used to let my bike sit out in the sun before school started just so it would deice.
24 degrees and 90% humidity. WOOHOO FLORIDA!
edit: F not C.
I had it real bad this morning so I pulled over and stopped the bike. It was perfect after less than a minute.