2001 Ds 650 issues
 

I just bought this wheeler, and it ran perfect when i bought didnt see anything wrong with it all, i was riding down a dirt road and the headlight shut off and it started idling high, and then it was about to stall then felt like i hammered on the throttle but i didnt touch the throttle, I brought it to my buddys house to figure out that the intake boot was ripped and the carb flange was a piece of radiator hose, i bought the parts and put them in and it would on run on choke, Then i cleaned the carb, still only run on choke, turned the idle all they way up and it runs but it doesnt even idle high, im confused. When i was going down the dirt road, after it backfired and stalled i had the clutch held in and i was shifting down, when i shifted from second to first, i could feel the shifter slapping the bottom of my boot and it didnt sound good. now i can get it to run and ride for a couple minutes then my oil pressure will drop and it stalls. Only thing it has for upgrades is a FMF powercore 4 slip on, and a oversized piston, idk if the guy meant its bored and a bigger piston or if its just after market, and i just drained the oil out of the motor and there was a little bit of metal shavings in the plug and a metal ring came out when i put my finger in there, it looks like apart of some threads, please help.