My 910 fouls plugs every time I ride down the canyon on the way out from riding. Runs great up the trail and in the mountains but drops cylinders as soon as I hit the trail out. It switches switches between the mag and pto and completely dies. If I let it idle for a minute it is fine for a was then it does it again. Plugs are a light tan and I have tried br9eix, bpr9eix and br9eya. I have tried dropping the needles but seems way to lean going up the trail. Any ideas I can try?
Carl's 910 fouling plugs
- Thread starter lords88
- Start date
Hmm... never had that with my 910. I wonder if your coils are getting weak... at low rpm, no load they don't fire well enough? Just guessing. Does it actually kill the plug and you have to replace it?
sled_guy
sled_guy
The iridium plugs are fine after idles for a minute. The br9eya's I tried died and had to be replaced. Plugs are a light tan. With 30% AV fuel and blue marble oil. Newer style needles in the 2nd clip. Egts are around 1000-1100 when it happens. I am thinking of dropping the needles one clip to the # 1 position but I like how it runs now going up the trail with egts from 1150-1200. This happens from 7000' up to 9,000ft. I do most of my riding from 8000-10000ft.
That is the altitude I ride at too. Be VERY careful with that clip move, watch your temps close, the 910 runs dang lean in the midrange even with the newer needles.
Just for grins, check your choke cable and make sure it isn't a smidge too tight and holding the chokes slightly open.
sled_guy
Just for grins, check your choke cable and make sure it isn't a smidge too tight and holding the chokes slightly open.
sled_guy
Well this thing is still giving me fits! I have tried dropping the needles as far as they will go even with the white washer on top the e-clip in #1 spot. I have replaced the stator, swapped the cdi, coils, tried running with pods, checked reeds, compression, checked pipes for obstructions, changed the float needle seats, cleaned the carbs, tried all sorts of air/fuel screw combinations, new temp sensor and a resistor. My mag side plug always looks black and clean like charcoal and my pto looks brown and shiny. I am at a loss on what to do. Thinking about trying a set of 02 needles.
By chance is the gas tank vent plugged or restricted and building up pressure in the tank and pressurizing the fuel system with change in elevation.
Where are the carb vent tubes ran and have you tried a different set of carbs.
Yes, the carb vent tubes are ran to the air box, I have tried them unhooked and same results. Tank vent is good and even tried with fuel cap off to ensure that wasn't the problem. I was going to try to another set of carbs this spring but ran out of snow before I could try a set.
