How to upgrade your stock carb to the 39 pwk

[slamdak8782]

i just changed my stock carb for the keihin 39 PWK. This is an awesome upgrade. My R will now just about rip the bars out of my hand It is a lot of fun. Installation was very straight forward and I felt like it was a factory upgrade. This will make your stock bore and up come alive. I did lose some low end but I think that will come back after I am done jetting. I will probably be putting the power now kit on there to see if that really works. To get the carb on the stock air boot you will have to put the boot in boiling water for about 10 to 15 minutes and then strech it out with a small jar or a tapered object of some kind after that it is very easy to do and it works very well. My R is 20 over and I am very impressed with this carb. I will keep everyone posted on how the power now works out

[slamdak8782]

Oh for the front part of the carb I have a rad valve setup with the spacer

[beerock]

did you get that cel needle?

[Antony250R]

What size bore are you running? What other mods are done to the engine?

[slamdak8782]

The bore is 20 over Im not sure about the needle yet because I havent rejeted it yet I will let you know though soon. It has a rad valve lrd pipe with a fmf silencer. Im going to the fmf fatty though as that seems like a good overall pipe

[slamdak8782]

here is what I found today
1. 168 main
2. 60 pilot
3.38 float bowl jet
4. DGH needle
How does that sound. Idle with the idle about 1/4 turn out airscrew I am not to sure about that one
What do you guys think
Need to find somewhere to get the jets

[slamdak8782]

Ok i changed out the needle to the CEL needle and wow what a difference. Midrange is nuts now and off idle is pretty good too. Im still working it out but, so far
168 main 60pilot 38 throttle airscrewout 2 turns and fuel is out 2.5 turns. So far Beerock this is awesome.

[hollywood250r]

If you think the CEL needle is nice try out the CEJ needle! You will love it over the CEL needle.

[slamdak8782]

alright I will give it a try

[hondardr4life]

Ok, its a stupid question, but what is a rad valve?? I have a boysen reed cage from what I can tell, and I was wondering how you tell if its a rad valve, and what difference a rad valve actually makes. It's kinda of a newbie question, but oh well.

[slamdak8782]

Rad valve is just a brand. Look at the reeds and reed cage it is probably stamped on there on the inside

[slamdak8782]

I ran the cel needle today and I really dont want to change it. It is alot faster tan the dgh I was running. I may give the cej a try though

[gunslinger]

Where did you get your 39 from if you don't mind me asking.

[Eddiesanders250]

I got mine off ebay. pro-flo is the cheapest brand new that i know of. I tried ordering from them but unfortunately they were back ordered, 2-3 months.

[slamdak8782]

I got mine on this site and if you watch you can find them pretty easy on here. Also sudco.com and a lot of big name builders sell them as well. Ebay is always an option too.

[tater_kamik]

gld to hear your still throwing parts on there tom, how do you like your r now?

[honda380]

i think i may have the same carb on my bike, but i dont know how to tell. it may be a 38, i have no idea, there are numbers but i dont know how to read them, i was just wondering what the needles do and how much they cost. thanks -Corey-

[HiperEX]

im running a kiehen 39mm on my 265 with boyesen rad valve and reed spacer, power is awsome all around also has mx port work and pro design coolhead i will check for sure what jetting im running

[beerock]

Originally posted by HiperEX
im running a kiehen 39mm on my 265 with boyesen rad valve and reed spacer, power is awsome all around also has mx port work and pro design coolhead i will check for sure what jetting im running
for any 265 check your needle and if its not a CEL I garantee you you will gain bottom to mid if you put the CEL in

[250R_4_ever]

You said you lost alot of low end
Are you sure your pilot jet is not to fat ? 60 seems pretty Fat
im jetting my 36mm pwk with a semilar settup and a 55 was way to fat (started and idle without the choke)

If your pilot is not the right one you will lose low end and throttle response in the low end

A improperly set float will play alot on the pilot jet too

Im not done jetting it cuz the jet Were B/O at my dealer but I order 52 50 48 ill let you know

I know every R's are differents

just my 2 cents :blah:

[300exQuadracer]

i`m running a DGJ on a 38mm with a 310 big bore the CEL/CEJ make a big differnce in responce??

[707trx250r]

Is the cel richer than a ddj. What makes it better?:confused:

[slamdak8782]

just try it and youll see.

[hollywood250r]

The CEL is just a little lean at 1/4 throttle and below. if you have the CEJ and the CEL, put in the CEL first, then put in the CEJ after some seat time then you will see exactly what the straight segment of the needle does for the powerband. You will love the CEJ!

[707trx250r]

I just ordered a cel and cej from magic racing. I can't wait, i cant believe my bike can be faster!!

[dober250R]

I'm running a 265 with a J needle...................... so, which one is better, the J or the L?

[slamdak8782]

who ran both is it worth it to switch from l to j

[snapon]

were you able to use your stock throttle cable with the PWK carb?

[slamdak8782]

I still was able to use the stock cable. But the twist throttle uses a different cable