engine started having loss of power.

[Mr Rogers]

Hey all,
So I brought my bike out this summer and got it running swimmingly.
But that only lasted two weeks.
I went out this morning and turned the bike on and I couldn't get it to stay running after I started it. In order to keep it running i had to really rev the throttle but the engine didn't respond at all like it normally does. usually it's nice and loud but this morning it sounded like everything was muffled puttering.
Also if I put it into gear and try to ride it's too much and the bike dies immediately.

Does anyone know what's going on?

[eil]

Mice in the airbox or exhaust?

Did you maybe put old gas into it by accident?

How's the oil level? Good or overfilled? Does it smell like gas?

Hard to troubleshoot this one without just tearing into it and eliminating suspected causes until you find the culprit.

[Mekanix]

Fouled spark plug. Running on one cylinder.

Start there.

Then check for fuel clogs.

Then check each carb to make sure they are getting fuel.