big bore keihin jetting

[cuzzinpaulie]

trying to get my bike jetted right. looking for advice. check out my sig for what im running right now. i guess my concern is that it was running rich and the biggest help was moving the clip to the top position.
when i do a search for jet settings it looks like every one else is on the middle clip and running a 150 or bigger main jet. im pretty sure i could go even lower on the main because it still seems a tad rich. am i ok for my mods and elevation or is something up? heres a link to a quick vid i did

 

[Awk08]

at my 1800'+ elevation, 34mm PJ, heavily ported stock cyinder.
the CEL needle was too rich for me, mine likes the DGH needle in the middle slot.
if you're in the top slot and it likes it, thats a candidate for a leaner needle.
50 pilot sounds right, i run a 48 (elev.) and a 155 main w/ right bend pipe.
the FMF requires less jetting than my pipe, but balanced out by your much lower elevation.
i'd try a 150 thru 160 mains
start large and plug chop down.......

http://wheeling.craigslist.org/cto/4379933712.html


edit: just watched the vid
was that bike warmed up properly before you tore off wide open down the road ?
couldn't really tell anything else, couldn't tell if you were letting off or it was bogging ?

 

[cuzzinpaulie]

any advice on next upgrade

 

[cuzzinpaulie]

i did work my way down from 160 all the way to 140, then put the clip from second to top position with a 155 and it was better but still rich. so now im at 145 and its better but i think i could go down more. like i said im just concerned because those numbers and clip position does seem to match up with others. ya the bike was warmed up from prior jet changes and yes i was letting off of it. i didnt want to push it hard until i feel its safe.

 

[Awk08]

i did work my way down from 160 all the way to 140, then put the clip from second to top position with a 155 and it was better but still rich. so now im at 145 and its better but i think i could go down more. like i said im just concerned because those numbers and clip position does seem to match up with others. ya the bike was warmed up from prior jet changes and yes i was letting off of it. i didnt want to push it hard until i feel its safe.

the jetting numbers you see on here.....
are mostly on ported cylinders, stock and/or big bore.
the porting makes a huge difference and most of us do that then need the bigger carb to go with it.
and mostly on 34-36mm carbs, which slows the velocity of the air versus a smaller carb.
so it's possible the added air velocity of the smaller 33 picks up more fuel and does need leaner jetting ?
i'd try a DGH needle too

gotta do them plug chops too, not just by feel, lean will feel wonderful until it seizes

 

[cuzzinpaulie]

ya ill order a dgh needle and do some plug chops. any advice on next upgrade? i like a real snappy bike. i want the handle bars smashing me in the face.

 

[DUALSTROKE]

ya ill order a dgh needle and do some plug chops. any advice on next upgrade? i like a real snappy bike. i want the handle bars smashing me in the face.

Then get some porting done to that slug of a big bore. In all seriousness that cylinder will wake right up with some good porting. Port it and that cel needle will be just fine.

 

[cuzzinpaulie]

ya porting sounds good. thanks for the info

 

[DUALSTROKE]

Porting comes first, then you will sell the fmf and get a better pipe for the ported bb. Can you say all smiles

 

[cuzzinpaulie]

were do you have porting done and how much?

 

[Awk08]

were do you have porting done and how much?

http://kenoconnorracing.com/Two Stroke Cylinder Porting.html

get the head modified too, then hang on tight

 

[cuzzinpaulie]

thanks

 

[Wifesblaster]

You might want to look at getting your flywheel lightened too.