I just bought this 2000 Quadmaster 500 with 1200 miles and it seems to run great except for the annoying exhaust leak. From the pull start side of the engine you can see a crack about 1/2" long, "along the edge of the weld" right in the bend next to the head. It's not leaking a lot, sounds like a blown exhaust gasket but it's this crack and it pops a little when letting off throttle after revving it up. Occasionally backfires a little when shutting off. Nothing drastic but obviously noticeable and worrisum. My concern is it will damage the engine from having this leak , maybe warp a valve or worse when I shut it off after running it for a while. Always heard that no exhaust/or leaking exhaust can suck in cold air and cool down to quickly causing damage. Can someone please give me some insight on this problem, do I have to worry or can I still ride the machine unitl I have time to fix it? Is it hard to remove to the exhaust from this machine, I can't see where it's all attached and it looks like a real pain in the neck, no manual yet either. Your help would be highly appreciated! Thank you

 

Go to the parts store and pick up a tube of JB Weld. If you can see the crack you should be able to get to it enough to smear some on. Worked good enough patch a hole in the exhaust of an old truck I used to have and get it to pass inspection. Not really a permanent fix but I drove it another 6 months before selling it and it was still holding up.

 

with an exhaust leak that close to the head you can burn a valve because it can lean the motor out a little, Ive seen it happen in car and truck motors