I have a 2009 S40 with a RYCA Scrambler conversion. 4800 miles. Did a morning 20 mile commute yesterday morning and everything was running fine.

During my afternoon commute, as I merged onto the highway, I felt a loss of power trying to go from 55mph to 65mph. All of a sudden, the bike started sputtering and died. I had to pull over onto the shoulder. I managed to start the bike back up and got back onto the highway, but the bike felt weak and eventually sputtered and died again.

Finally, I decided to pull the choke out and start the bike. I was able to ride the rest of the way home with the choke out and it seemed okay. I did not take it over 55mph.

What seems to be the issue? I had thought it would be a fuel issue, but with it running okay with the choke out, it has me stumped. I tried searching the forums and similar problems have to deal with the stock petcock (I have a raptor petcock installed).

Thoughts? Thanks in advance!

Petcock?

It sounds like the bike went suddenly lean,I'd be looking at whatever was used to plug the vacuum port in the carb for the old petcock , or the mounting boot/clamp between the carb and head.  a leak there would lean the fuel mix ,the fact that running with the choke out seemed to compensate ,tells me that fuel must be getting to the bowl,(enough to do 55)which rules out almost anything else except a plugged  jet.

My first week with the bike (the other bike I had before the savage had a gas gauge), I ran out of gas and pulled over to the side of the road. The front of the bike was facing down hill.

There was a guy fixing a flat on his bicycle who asked if I was out of gas. I looked into the tank and saw gas and stated that I definitely had enough in it to at the very least get me a mile down the road to the gas station. It turned out that gas couldn't get to the petcock and into the carb and looked like I had plenty of gas because it moved to the front of the tank.

I called a tow truck (thanks progressive!) and also asked a buddy to come and drop off a gallon of gas just in case (even though I was sure that wasn't the problem). Thankfully my buddy got to me before the tow truck did. I called progressive and told them to cancel the tow truck and then headed to the gas station to fill the rest of the way up. That's also when I learned that the petcock has a regular position as well as a reserve. The previous owner left it on reserve and I never changed it.