Sudden deterioration in starting ability

I recently bought a 2001 YZ125, very clean. I rode it for a while, but left it for a few months. It used to start first or second kick, but I left it for a few months and now it takes forever to start and doesn't even sound like it wants to start until it seems to suddenly burst to life.

Before I left it for the few months, I ran it in the cold and I think the float stuck and the engine was cutting at high revs; I hope I didn't damage it (anyway I only rode it for a few minutes like this). It fouled a plug, so I changed it, and tapped the carb bowl to free the float. When I pulled out the plug, it was very oily. It ran well when I did manage to start it, but then I stopped to take a break and tried to start it and it took forever again. I am running the same premix ratio as the previous owner did, but not same brand- problem?

The problem is I don't live where I keep the bike, so I can't start the engine every week or month or so to keep it healthy.

Anyone have any suggestions to what is wrong?

crank seals is my guess

prolly time to rebuild her

Huh? A complete engine rebuild? All it needs is a pilot jet cleaning. At least look at it before tearing down the whole motor! Next time before you put it away drain the float bowl. There is a 17mm bolt at the bottom of the carb. Or turn the gas off and let it run till it dies.

Huh? A complete engine rebuild? All it needs is a pilot jet cleaning. At least look at it before tearing down the whole motor! Next time before you put it away drain the float bowl. There is a 17mm bolt at the bottom of the carb. Or turn the gas off and let it run till it dies.

+1

Sounds like the carb just needs a decent cleaning.

Agreed with the carb cleaning id also recommend checking your reeds

Check the cylinder and piston as well. 125 top ends can go from fine to low compression in the course of an hour.

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