white bros. e series jetting question

bill wright · Mar 20, 2011

ok , i had bought a 99 warrior with a blown motor. all stock with a white bros. e series pipe. the piston was grenaded, cylinder sleeve broken , con rod bottom end bearings completly gone, con rod bent near the top, piston peices all through the tranny, glitter every where. i completly tore it down to the last bolt & seal,& rebuilt it to new stock specs.my question is,does anyone here know the baseline jetting recomendations from white bros for a new, stock bore,stock piston & rings ,stock stroke , stock carb,stock airbox, uni 2 stage foam air filter with a white bros. E series exhaust?. generally 55 deg. F to 105 degrees F,(average temp about 85 or so) generally 1000 - 4500 feet above sea level. apparently white bros. got bought out by vance & hines, & i am not getting a response from V& H. the carb in the blown motor was stock, however, the jet needle appeared to be aftermarket, as it had NO grooves to change the clip position.also, the spark plug had a white ashy look, indicating an ultra-lean a/f ratio. any body out there know the white bros. jetting specs? or where i might find them? any help is much appreciated. thanks, bill.

elwood · Mar 20, 2011

I think your just going to play the jetting game. 1st, warriors came a little lean on the pilot jet. Stock is a 42.5 I'd bump it up to a 45. 2nd stock needle in the middle setting (there are 5). 3rd Stock main is a 145 I'd get a 147.5 and a 150 then see what one works best off your plug reading and engine preformance. last fine turn with your air/fuel screw

Deuce · Mar 20, 2011

I wish I could help you, but elwood is right.

I have a E series, but I'm also running a z400 carb, and had to do the same thing and play the jetting game until I got it to be where I and it wanted it to be.

bomber315 · Mar 21, 2011

elwood is completely right, i have a eseries, but i also have a 10.25:1 piston... im running a 45 pilot and a 150 main, needle is in the center and i dont know exactly where my screw is but thats is the part youll just have to mess with anyways

bill wright · Mar 25, 2011

first off, much thanks to y'all that responded to my question. i finally got ahold of v& h . they looked up the jetting recomendation from white bros technical info., & for my set up it says stock yamaha jetting. still, i bought a 42.5& 45 pilot jets, & 145 & 150 main & a stock jet needle set from the yamaha dealer. i will start rich & work back if necesary, by doing plug chops.
if any one needs the phone # in regards to technical questions on WHITE BROS. pipes,you can call the VANCE & HINES TECH LINE @562-926-5291 between the hours 8:00 a.m. - 5:00 p.m. pacific time.

thank you again to ELWOOD, DUECE, & BOMBER 315 for your input.

regards, bill

mattskn · Mar 25, 2011

post up your findings, save me from asking the same questions.

bill wright · Mar 30, 2011

havn't put them in yet, but i picked up the parts, my initial observation is the stock jet needle kit for 1999 model has only 1 GROOVE (no clip adjustment).yamaha part # 3gd-1490j-10.hmmmnnn..............time to dig out the manual.......