[Airborne500]

Hello all,

I am new to the forum as I recently purchased a 2012 Classic 500 with 7000 miles. After putting 1000 miles on it I noticed that the performance was suffering as it began hesitating / sputtering and finally it would start but not run. I went about routine maintenance. Along with a rear tire change, I took off the tank and replaced the fuel filter (it was cogged with rust colored material) and finally changed the oil and filter. I made sure that the oil is between the fill lines and it starts right away and idles well after it warms up. Here is where the problem starts, put into first gear and the throttle is unresponsive and only seems to get going with a little help from the clutch. Then it will go for a couple of seconds and start sputtering and the the metal cover that goes over the air filter will blast open as there is a backblast through the air filter. Any and all thought / comments are 100% appreciated.

[oldphart]

You're using the wrong swear words 

I think my first step would be to go looking for air leaks. That black tubing RE uses only masquerades as rubber and can fail very quickly... or not at all. Real weir stuff.

I did think of suggesting the plug but that wouldn't explain the massive back fire (I don't think... but what would I know).

[gizzo]

Fuel injector might be blocked with the same crap that was in the filter. Idling but not driving, spluttering, backfiring all symptoms of lean running.
A fuel injection specialist will have the tools to clean the injector and test the spray pattern.

[Airborne500]

Thank you both for your replies.

[ace.cafe]

A known issue was the plastic fuel line from the fuel pump was kinked, preventing sufficient fuel flow to the injector. Later models cured that.

[Guaire]

I had the bent fuel line disease for awhile. It was awful.
I would add a dose of Sea f o a m to the fuel. Then while idling I'd squirt a quick shot, spray, of Gum Cutter. That will help unclog the injector as well.

[Airborne500]

In the end it was the fuel injector. Cleaned it out and runs perfect now. Thanks for all your suggestions.