i am newbe here, don't blast me about search first i did and everyone here knows the search sucks here. i don't have a manual for the 400 , on the fuel petcock i got on , res , prt. what is prt and where should put when riding and storing it, i rode it the other day on prt and it rode fine

its actually pri. and its prime for priming the carb all it does is lets a steady flow of gas to the carb to store you should put it on the on postition.

Its a vaccum operated petcock meaning..

'On' only allows gas to flow when the motor is running and making vaccum.

'Prime' allows gas to flow even when the motor is off. (This is what you will use if you ever switch to an FCR carb)

'Off' is simply off.

There's no "Off" for the stocker, man. On, Reserve, and Prime only. The only way to cut the fuel flow is with it in the On or Reserve position, engine not running. If fuel does flow in either of those two positions, engine not running, then it means the diaphragm is torn, internally.

Yeah you're right. I just went out and looked at it again lol.