Exhaust smell

[702scottc]

Currently on a long ride to Pacific nw and I'm getting an exhaust smell from time to time, smells like a hot catalytic converter on a car. Only for a second or 2 and when I shut it off to get fuel. Mileage is fine, power is great. Just never noticed before I guess. Anyone get this as well? Factory exhaust.

[GoldWingrGreg]

Year and mileage is always helpful !!! Yes I see your Avatar says 2005, but for all I know you're asking about your buddies Wing, or you've upgraded to another year.

5th gens should not have that kind of smell. Any miss firing, hesitation, wanting to die, idle surge ??? Pay close attentions while shifting gears for hesitation. 5th gen Wings should have extremely smooth acceleration. Common things that can cause smelly exhaust:
- poor firing plugs (should be replaced every 16k with the ones Honda says to use)
- restricted air filter (should be replaced every 12k)
- additive in gas
- aftermarket exhaust
- something beginning to fail in the PGM-FI system
- gas with higher than 10% ethonol

While riding, does your FI light ever come on ??? If it does, pull over, do not shut engine off, shift into "N", and put side stand down. The FI light should start to flash. Count the flashes and do the math. A long flash = 10. A short flash = 1.

For example ... long + long + short + short + short + short + short = 25. Then report back. Those flashes represent DTC (digital trouble codes). The above example would be "code 25."

[702scottc]

All stock 2005. No F1 lights, runs fine, no misfires. I have been using 87 octane fuel but the mileage has been between 38 and 40 mpg. Air filter has about 12 k on it. The only thing that I have done to it differently was replace the spark plugs 4 months ago. I used the oem plugs but removed the colder recommended plug for high speed driving. Not sure if that's the issue or not. Rode from Vegas to Seattle this weekend for the game. Will be heading home tomorrow. I usually use 89 octane but the price has spiked so i used 87 to save a little money, always use Chevron or Shell. I'll run 89 on the way home. My first thought was a PAIR system issue. It smells like a hot catalytic converter but only for a second or 2. The bike runs fine , it's just an occasional whiff. I have been running 80 and 85 most of the way up here. The closed thing I can compare it to is when someone passes you on the interstate and you can smell the cat when they are pushing the engine hard.