I recently ordered a 39 pwk carb what jetting should i run my bike is a scrambler 400 with a hpd pipe k&n filter clutch and this carb. I am near sea level what main jet? pilot jet? needle clip position? any help would be appreciated.

 

I also run the 39pwk. When I had it trail modded with the HPD pipe, it came with a 45 pilot jet, and a 168 in the carb. I had to jet the main down to about a 162 to run the best, but be careful right now because the air is cooler and more dense. I used the needle that came with it and had the clip in the middle. The HPD trail pipe likes it fat on the pilot and pretty fat on the jetting in the midrange. Remember, always best to start out rich and go leaner if you need to. I am going to be close to you on altitude.Bubba

 

Who did you order the carb from? Did they know it was for your bike?
Prejetted carbs will be close, but as was stated before start on the rich side (safe) and work your way to the proper jet.

Try Sudco for carbs and parts. One tip though, find what you need on their site and find a dealer who will cut you a deal. I saved amost $100 on my new 41mm.

 

here is the main jets setting from HPD:

162:stock bore
165:trail porting
168:race porting.

pilot is in the 40-45 range,the needle setting is up to you by watching the spark plug color at mid-throttle setting (probably 2-3 clip)

 

Scramblered, that isnt always right. I run a 162 on my race mod setup in the spring and summer, and only a 165 in the cooler months,Bubba

 

yeah i know what you mean,i was not talking about FINE jetting at all,this is just what HPD told me,jetting is always relative from an engine to another,actually i run 162 main with the whole trail mod kit and still on the rich side,but you must always have a starting point then the job is yours with the spark plug color and piston wash to get this whole thing done...

 

i ended up running a 170 main and 38 pilot any ideas why mine is flowing more that other bikes with more mods? now that i've removed my injection im running a 175 with still just a pipe and this carb.

 

I run the race mod and my jetting is 178 to 180 main and 35 pilot.Oh yeah i'm below sea level.[img]i/expressions/face-icon-small-cool.gif[/img]

 

I run mine with a 38 pilot,needle all the way up,and a 175 main,and I am at sea level.