Ok-1996 zrt 800 just bought-previous owner had a small fire and redid the fuel lines backwards which is why it would only run on two cyl briefly. fixed that problem. Previous owner also said he had not ruin it for 2 years. check everything over and I go to the mountains. did the carbs as well top to bottom. go out for a couple hours, check plugs(choco milk coulour). trailer it go to a bigger mountain. offload starrt5 let it idle for 3 minutes (0 Cel outside) Jump on and go half power or so-3km later it runs bad on 2 cyl then dies. Check hood, check plugs all 3 good. Start it and no prob. Go another 1 km and it dies. open hood and Coolant leaking at base of jug next to clutch. I leave it there and ride a diff sled the day. Tow it down later and pullo it into shop to replace base gasket.(what makes a base gasket go?-dries up?backfire?) Anyways - get the jug off and the rins are a bit melted into the piston and the jug is scored very slightly. No spare piston with me so I pull the cover off the 86 formula plus with the conveyor belt to get me through the rest of the weekend. my back still hurts. Anyways--there was slight backfiring here and there when we first started it up, but other than that once we drove it for 2-3 hours in the morning it was fine. The piston looks scored on all sides but it is not burnt on top. I am about to order the piston kit to fix the problem but I want to make sure there are no other problems that would cause this again. Also when i got the piston out there is a small tab of metal inside the crankcase at the back on the carb side right in front of the reed valve, it has a little slit in it. This is broken off on the bad cylinder-only about a 1/4" though. (hopefully this wont matter too much as long as I get the metaql out of the case...right?) I am all ears Oh wise Ones....Pleaes help.