Sportster Plugs

Buddy has an 01 883, 15K on it all in Florida. We recently trailered it up to the mts of NC/TN (did the tail). Bike ran good, though he said he noticed a slight lack of power. Got back to Florida and the bike sat for a week or so. He tried to start her up and it was rough, wouldn't hold a steady idle with the chock out or in. Pulled the plugs and they were very black and coated, cleaned them up a bit. We got it to idle but still very rough, got it in the road, a few backfires with black exhaust out the pipe with each backfire, after about 5 minutes of this, it started to run fine, no black exhaust with backfires, and idle was fine. Any ideals on why the plugs were fouled so bad (we changed them just before the trip with pre-set HD plugs). Bike run's great now, just curious.

could be the bike was a touch rich to start with, and the elevation may have caused it to run richer, causing the plugs to foul. Usually this would be more for higher elevations, but it's hard to tell. Smokies are around 4-4500 ft.

JMO. if it runs fine now, I wouldn't worry much about it. This happens with carbs sometimes.

RL