HMF slip on for newbee?

[Jim Anderson]

Hey guys i'm new here, be easy on me. i need a pipe for a '99 400 EX, stock except for K&N w/ outerwear & removed lid. whats the most bang for the $ also how should it be jetted in AZ at sea level.
the only problem now is that between downshifts from upper rpm's the engine will sometimes stall. any ideas?

[cals400ex]

hmf's are definately great pipes. i would consider one of those and i would start with jetting at a 158 main with the lid off and K&N filter. jetting is trial and error so some tweeking may be needed. i would also raise the pilot jet to a 40 or 42 while your at it.


i would do a good carb cleaning and make sure your fuel is fresh and the spark plug is new.