300/440/550 trouble tunning keihn after rebuild

just rebuilt my keihin 38mm carb on my 650
and i cant get the low end to do anything.

it will not idle at all, but if you prime it alot and rev right up to high end it does great revs back down and idles for like 1 second then die

i have tried .5 - 3.5 turns in half turn increments on the low speed and really not making any difference

what would make the low end not respond at all but the high end actually work fine?
 

tor*p*do

Squarenose FTW
Site Supporter
Location
NW NC
did you blast out the jets and orfices into the car bthroat?
sounds like gunk in the low speed circuit
 
its not idle speed because when it starts to die at idle and i blip the throttle it bogs

i blew everything like crazy with carb cleaner when it was apart, sounds like i should have blasted some compressed air through it

if i take it apart where in the carb would i wanna shoot some air?
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
There is a small black plastic piece that covers the bypass holes after you take the piec off that has the needle and seat in it,usually if you rap on the carb body a few times it will fall out,blow through all those holes with carb cleaner followed by compressed air,also make sure the filter connected to the back of the seat assy is clean and remove the low speed screw and spay carb cleaner and air through that also.
 
i know lazy isnt the way, but would just taking the low speed screw out right now and blowing air thru it damnage anything?

seems like i might blow a gasket apart, i think ill pass on doing that, time to take it off again haha
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
i know lazy isnt the way, but would just taking the low speed screw out right now and blowing air thru it damnage anything?

seems like i might blow a gasket apart, i think ill pass on doing that, time to take it off again haha


You could blow some carb cleaner though it but not air.
 
took the carb apart and all 4 little low speed holes were closed shut, cleared it out and rode

but to idle it still had to be almost 3 turns out....weird
 

tor*p*do

Squarenose FTW
Site Supporter
Location
NW NC
took the carb apart and all 4 little low speed holes were closed shut, cleared it out and rode

but to idle it still had to be almost 3 turns out....weird

I use a twist tie off a loaf of bread
pull back the paper and use the wire to rod out these holes.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
I use a twist tie off a loaf of bread
pull back the paper and use the wire to rod out these holes.

I usually use a stranded copper wire,peel the insulation back and remove one strand from the wire,its copper so its not as hard as the brass jet and there is no possibility of scratching or otherwise damaging the jet.
 
Top Bottom