03 YZ450 Leaking Coolant on Cylinder

I have an 03 YZ 450 and it blows radiator fluid out of a small hole above the exhaust(Brake side). The hole is about the diameter of your little finger. At first I thought it was a radiator leak and after the bike cooled I noticed a small drip from that hole in the cylinder. The fluid never ran down the cylinder and was burned off by the exhaust and what didn't burn was misted into the radiator on the right side (side with the cap). Please help.

It is the hole where your decompression unit would bolt up. they went to the auto decomp in 03 but left the hole. There are several threads about it. Just search this forum. Use key words "decompression" "plug" "leak". Good luck with your problem I hope that you get it plugged up soon. Honyam

Yep grays right sorry about that.

I installed the after market plug, works great!!! Thanks for the very important info and $$$ savings. The info on this board is priceless.

Thanks again.

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