Bike thinks it has no fuel in main tank

[LondonRR]

Hi
2022 250RR 2T
New issue (first problem I have had with it).
Only thing I have changed recently is swapping the spark plug.
The bike is now bogging/cutting out like it has no fuel (I am sure they are "no fuel" symptoms) far earlier than it should/did before/with plenty of fuel still left.
Switching the tap to reserve, it is then running fine.
No other running issues.
I can run it on the reserve setting all of the time, but I'd much rather not do that, and have the "warning".
So seems to be an issue with the float/sensor or fuel tap, "it thinks it is empty but it isn't".
Has anyone experienced similar or have an idea for a simple fix please?

Thank you

[JoeMaico]

Typically, your description would be a symptom of a clogged screen in the tank filter. But with a 22, I doubt you have run that many tanks of contaminated fuel through it. So, I would check the fuel petcock itself for issues. First simple check is to disconnect the fuel line from the carb and observe the flow rate in both the 'on' position and reserve. If it is a noticeable difference between the two with a half full tank (or higher), then you know your issue is either the filter or the petcock.

joe

[LondonRR]

understood, thanks

[idahosingletrack]

I had the exact same symptoms with my 2023 250 rr. Turns out, these beta's have a super long reserve. The fuel line that goes up into the tank is about 4 inches long (into the tank). So I thought I had plenty of fuel in the tank and ruled out fuel starvation when in reality, the main "on" position on the petcock couldn't pull more fuel. Turning it to reserve, the bike started quickly and ran fine.

[Hyde]

Beta's hit reserve at about 1/2 a tank, kind of makes sense, if your 25 miles from the truck when you hit reserve, you'll make it back to said truck.

If your new to Beta and the green valve under the gas cap hasn't fell off yet, pull that off and toss it.