390 RR-S 2020 backfiring, hesitating, fuel blockage?

[whitey]

Have 2020 390RR-S. Approx 4,000 mi. Flawless performance from day 1. However, during ride today started backfiring and seemed to have a lag in response when twist throttle. Also seems like it’s intermittently starving for more fuel. Something is amiss. Mapping switch seems to be functioning properly. I always have it for sunshine here in SoCalif. Any suggestions/experience as to what I may be dealing with? Fuel pump? EFI? The backfiring like a carb bike has me scratching my head. Thx

[Trailbear84]

I would start by checking your fuel filter or just replace it since you're going through the trouble of pulling it out of the tank and work from that point.
Could be as simple as a filter, kinked line, bad spark plug. I would start with those items and then verify good consistent fuel flow from the pump. Other culprits could be fuel injector, ignition unit, or timing issue, but I would start with simple most likely issues. I'm assuming the fuel is not deteriorated and fresh. Good luck! I have the same year 390 and have been problem free, so your fix will be interesting.

https://www.youtube.com/watch?v=VB5ZkvIxpls

[pscook]

There is a chance that you got bad gas. A good friend had the same issue with his bike and his boy's bike. Both back to the dealer for service, they couldn't replicate the problem. he got the bikes back, called me and another buddy about this, and we told him to replace the gas. problem solved.

If new gas, from a different fuel station and a different jug, doesn't solve the problem, I would do these things:

Pull the tank, replace the fuel filter, replace the sparkplug. Since you have the tank off, pull the injectors and check them. You might want to hook them up to the fuel tank and actually spray fuel, or at least perform a visual inspection and reinstall.

If the problem persists, send the injectors out for cleaning and see how to replace the fuel pump. Taco Moto has a fuel pump for us that isn't terribly expensive (when it's in stock).

https://tacomoto.co/products/california ... 4754561127