Jetting nightmare!!!!

[baker250r]

270PV + Amsoil Intimidator + 110 Sunoco at 32:1 + 38mm Carb + Sparks TT pipe = NIGHTMARE!!!!!


lol. ook. thats wut im running. i have been fist f*cking around for too long. cost me 4 races now. i cant get this jettin right for the life of me. right now im at a 150 Main, with the needle in the top position, so the needle is all the way down. ferget wut my pilot is.

its been HOT and humid here lately... i dont know if that has anythign to do with it or not 100's and very humid.

i start out... the jetting all seems fine.. everythign runs smootly till the engine gets warm.... then my midrange gets very doggy... (rich) and then it ifnally cleans out and runs nice till i get ot the higher RPM's and then it starts to spit and sputter. (lean?)

I take out the plug and it looks like its running perfect.

if anybody knows where to even start, id be really appreciatiive... cuz at htis point im about ot rip my hairs out. this PV is becoming a nightmare. i finally got the coolant problem fixed, and now this.

[hang1p]

in maine at 500ft and its about 90 degress around here with a 38mm airstiker now this is for my 350 and my friends stock bike 4th clip from the top 50 pilot 1.5 turns out and a 182 mj and 50 to 1 amsoil dominator give or take a little on the jets

[86 Quad R]

what needle are ya running?
is the float valve working properly?
if so, is the float level set properly?
have you done a leak down test on the engine?
do you have another carb to try on the quad?

a 150 i mighty lean in me opinion. and to have the needle all the way down? i dunno but, something isnt quite right. there is a slim possibility that the orfic in the carb is worn out.

:confused:

[zedicus00]

just from experience i always found it worked best to stick the needle in the midle clip and then change jets to get it whare it should be. once you get the needle to one extreme or the other they just dont perform right. yes i would also think 150 is a bit lean but the high humidity could play a part there. what needle are you running?

[machwon]

What needle do you have?

48 pilot
185 main

and a new spark plug at .018-.020" plug gap!

[baker250r]

not sure wut needle i have... i would look at it, but its a hour away right now... wont be able to get at it till friday night. wut needle do u reccomend?

[beerock]

sputtering up top? check your ground and ignition system out.

[baker250r]

its a cr250 setup. all stock cr250 parts. the ground is connected to the bolt that goes thru the top radiator shroud mount..... should i relocate it? i never had problems iwth this b4.

[beerock]

Originally posted by baker250r
not sure wut needle i have... i would look at it, but its a hour away right now... wont be able to get at it till friday night. wut needle do u reccomend?

what needle is in it?

i dont htink thats your problem since your bike use to run good right? but you could try a CEL needle with the clip one down from middle(raising the needle)

i think something else is wrong..

[baker250r]

do u know the part number of the CEL? i went ot my honda dealer and they all looked at me googly eyed.

[beerock]

its a keihn needle call up sudco and order it

get some plugs while your at it there cheap through them....

mayeb your coil is shot, i still thnk you need to check your electrical connections and system

[baker250r]

hmmm. thats a possibility.... will a stock trx coil work with the cr250?

[beerock]

i dunno, if there around the same draw sure..

[baker250r]

got it figured out. the ground wire was corroded really bad... so i replaced that and it took off.... now im at 195 main, 38 pilot, and needle all the way down.... everything runs pretty good. little bit of a lag in the bottom/mid. but i htink that might be the way the motor is setup.

[beerock]

Originally posted by baker250r
got it figured out. the ground wire was corroded really bad... so i replaced that and it took off.... now im at 195 main, 38 pilot, and needle all the way down.... everything runs pretty good. little bit of a lag in the bottom/mid. but i htink that might be the way the motor is setup.

had a feeling it was elctrical, do yourself a favor and try out that CEL needle, it will help your bottom end!!

[86 Quad R]

you also may wanna drop a couple sizes on the main to allow you to raise the needle a notch or two.

[beerock]

Originally posted by 86 Quad R
you also may wanna drop a couple sizes on the main to allow you to raise the needle a notch or two.

no ti doesnt work like that, you jet form WOT backwards, mid, low end

if he drops his main to bring the needle up it will run lean wot....


thats why i suggested the cel, because its a thicker needle....;)

[86 Quad R]

i'm aware of how the jetting process goes WOT(main) > mid(needle) > low(pilot).........

it's been my experience that the needle does have an effect on what the size of the main needs/should be. i've tried several sized needles in the same carb and also had to change the mains to compensate for what the engine liked. each circuit has an adverse effect on the others.

now dont get me wrong. i agree the if he's having to run the needle all the way down that a leaner taper is needed.

[C-LEIGH RACING]

Ya'll need me to call Jeff, :D :D AKA mindcrime the Kehien carb specialist.
Neil :D :D :eek2:

[baker250r]

somebody told me it could also be the hole in the carb might be egged out... and that could cause the needle always be off

[C-LEIGH RACING]

Originally posted by baker250r
somebody told me it could also be the hole in the carb might be egged out... and that could cause the needle always be off

I seen that happen to an old 230 Suzuki quadrunner carb. Ol needle had flopped around in the hole so much had just wore the needle & the hole out.
Neil

[86 Quad R]

lol neil :blah:


Originally posted by baker250r
somebody told me it could also be the hole in the carb might be egged out... and that could cause the needle always be off


"the hole" (orfic) sp can indeed get egged or wallered out and cause all sorts of problems. i've worked on quite a few that were like this. usually it's the older carbs that have been around for a while.

the last one i experienced was a pe 34 on a air cooled 250R engine on a drag blaster. it was soooo bad that you could set the needle all the way lean and install the leanest main and it still ran phat.

[beerock]

the needle on these keihn carbs pretty much all come from sudco and if not form there keihn direct and they pretty much slap in whatever they have....

two people have tried the cel needle for there 300c and under motors and it has done wonder for bottom end, im the third person that its done wonders for in my 265, just try it and youll see why

[86 Quad R]

i personally havent had much experience with the CEL needles but, have heard plenty good about them. what other needles in the C series do ya reccomend?

[baker250r]

well, the needle that was in it is a CEL.... now what.

[86 Quad R]

have ya got or have a buddy that has a spare carb laying around? i'd try another just for kikz en giggles.

[beerock]

Originally posted by baker250r
well, the needle that was in it is a CEL.... now what.


well if you have a CEL in there then your set
how is your low to low mid power?

[baker250r]

well the problems were comin from the CEL.... the bogging and stuff.... wut needle should i try now