i wil pull the carb this weekend and see what i have.

mods are
white bros r4 pipe
dg airbox
k&n filter
supposedly a jet kit was installed.

i would like to keep the set up the same but this thing just sucked in the tight 1st gear stuff on sat. at tower city.

on downhills the engine would stall. i must hve started it 30 times. just off idle there was a big flat spot where the engine didn't really bog there was just nothing, then when the throttle is pushed past halfway it would instantly pop up to around 2500rpm and from there up through the gears everything was fine.
the wierd thing was i could lug 2nd gear down to 0 mph and accelerate away cleanly. but if i pulled 1st down to nothing i would go through all the herky jerky acceleration again. i didn't really use 1st that much but when i needed to be in it it was making my life difficult(uphill,across rocks,with lots of turning and adjusting along the way is hard when you are either stalling or wheelieing)

anyone out there have a similarly set up 400 that wants to share jetting advice?


thanks,
mike

 

pull the carb off and clean it good. look at all the jets and figure out which size of jets are in it( all the jets say what size on the top) check the pilot jet forsure, and the fuel screw....turn it in til its LIGHTLY seated(count the number of turns)

does it bogg down in any other rpm range?? what is idleing like?? what about when you let off the gas, does it sputter or backfire???


are you sure its just the jetting?? check the front sprocket, and count the teeth. maybe its got a 15 tooth front sprocket and it doesnt like low speeds???


check your plug too, see what colour it is

 

it idles all day at a steady rpm. and it runs cleanly throughout the rpm range except for the hesitation in 1st. if i just mash the throttle in 1st it is okay. i am thinking there must be something gumming up the works in the carb. i will pull it this weekend when i have time and go from there.

mike

 

i'm going to say that you need to turn the screw out a little bit . if that works turn it in all the way counting the turns in and back it out the same number of turns,if its more than 3 full turns its time for a bigger air jet ,3.5 turns is the max.