Help with 500: bogging down

Bike worked perfectly for a very aggressive ride on Thursday in Moab. However, on Sunday it would bog down immediately after a G-out:

Ripping along at wide open throttle, fuel delivery fine. Hit a G-out and (1) low fuel light would come on, bike out bog like it was running out of fuel, sputter a little bit, then sort itself and run fine until the next G. I removed the gas cap vent hose / filter, didn’t help.

Rather than try to sort it on the trail at the start of another hard ride, I decided I had had 4 great days of riding, flipped it, rode back to camp to jump on the 790 and meet the B crew riding to Chicken Corners.

Wound it out in the way back, 90+mph, ran fine.

My thinking is to replace / address all things fuel delivery, as the bike has just under 500hrs and 12.6k miles: fuel filter, fuel pump, install an additional inline fuel filter. Might as well replace the fuel injector, new spark plug and check the valves while I’m in there.

Am I missing anything? It was weird, acting like a carbureted bike when the tank isn’t venting properly. And it was literally the first time I’ve ever seen the low fuel light

Sounds ultimately like a pickup issue. Weak pump, or maybe cracked line in the tank. Fuel sloshing around and it grabs air, triggering light and momentary bog.

Yeah, that makes sense

Time for the Taco Moto 3,000 hour fuel pump

I had a cracked fuel line in the gas tank of my 500. Mike Noone fixed it quickly. Good luck.

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Update: was a loose ground vs fuel issue. Fixed. Still going to pick up a new fuel pump, install inline fuel filter, etc

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Nice, and good call.

Damn, that’s what happened to mine on Gemini Bridges on day 1 in Moab. (Before the rekluse also fucked up)