Comming home from a long trip last weekend I hade to stop for gas near the St. Louis metro area. Anyway had to use gas with 10 percent ethenol. My TriGlide does not like that crap at all. Noticeable loss of power on hills and pinging. Slight backfire on decel. I refilled with good gas since then and it seems better. My question is, will bleneded fuel cause damage to my engine? Seems like in the metro areas all stations have blended fuel. Should this be avoided if possible? Thanks

 

As long as it's high enough as far as octane you shouldn't have any damage however ethanol will absorb moisture which may contribute to rough running.
I keep a bottle of octane boost on the bike at all times and use it only when the bike doesn't run right after a fill up.
Here in saskatchewan premium fuel isn't polluted with ethanol however there are only a few stations that have a dedicated pump for premium. The shared pumps take roughly 2.5 gallons to clear the line so unless the guy in front of you filled up with premium you pay for premium but get shorted.
Ethanol sucks but it won't cause any damage,other than to your wallet because of a reduction in fuel mileage

 

My wifes Softail Deluxe and my Tri-Glide seems to run worse with blended fuels but I allways carry a bottle of octane booster and that seems to help with our Harley's. I try to avoid it when we can but sometimes you have to take your chances but no mater what gas it is I always run the highest octain they have available.

 

If you do a lot of traveling your going to run into crummy fuel. Last summer when my dad and I went out west both our Triglides lived on a diet of 10% ethanol fuel which was pretty much the only thing available. I even ran a few tanks of 89 octane with 10% ethanol, my tune was dead on and I had no pinging and suffered no real noticeable power loss. The only loss I suffered was a loss of gas mileage which was to be expected. I normally carry octane booster just in case I get a case of the pings, I've been lucky and not had to use any since I swapped out the cams and got a good tune.

I see the OP has an 09, he may want to have a dealer see if it has the current download which addresses both pinging and heat. Given that our Government is in love with subsidizing the farmers buy pushing ethanol in the fuel I'm pretty sure it will get worse as time goes buy. Its been tossed around about going to 15% ethanol in gas.

 

A good write up of ethanol in Wikipedia:
http://en.wikipedia.org/wiki/Ethanol_fuel#Environment

Interesting points: ".... Ethanol contains approx. 34% less energy per unit volume than gasoline, and therefore in theory, burning pure ethanol in a vehicle will result in a 34% reduction in miles per US gallon, given the same fuel economy, compared to burning pure gasoline. Since ethanol has a higher octane rating, the engine can be made more efficient by raising its compression ratio."

Basic math then suggests that if 100% Enthanol reduces MPG by 34%...then 10% Ethanol should only reduce MPG by 3.4%...I assume then the same could be said on power. But, relative to the increased octane rating from the ethanol add...you still only get the rated octane. So, I would again assume that by increasing compression...as I plan to do with the SE255 cams...runs the risk of issues with lower octane fuel regardless of the content of the higher octane ethanol.

Guess I'll have to carry around octane booster.

 

If you do a lot of traveling to placed where ethanol treated gas is the norm then carrying octane booster is a wise choice. The year before last when my dad and I were running the SE255 cams we were forced to use octane booster on several occasions while in SD and the surrounding states due to pinging.

Last year while we visited the same area with the Wood TW555 cams we had no need to use octane booster. One gas stop we had no choice but to use 89 octane with 10% ethanol, mine never pinged a bit and power didn't seem to far off. My dad did have a little pinging on a few hills while bucking a head wind, but then his timing was pretty aggressive compared to mine.