Keihin PWK Carb Talk

[JB-250]

Im having a very hard time jetting the pwk carb DUAL vent; its hitting the powerband VERY sudden and not smoothly;

 

 

 

 

Whats the deal with the QUAD vent PWK? is there a main difference and is it worth $250 for a new QUAD vent PWK carb over the DUAL vent?

 

 

 

[shrubitup]

if you must upgrade your carb spend $50 more and get the Lectron from motosportz

[MGBGT]

What bike? What jetting? What needle? What slide? Stock bike? Modified? 

[mynewcr250]

Im having a very hard time jetting the pwk carb DUAL vent; its hitting the powerband VERY sudden and not smoothly;

 

 

 

 

Whats the deal with the QUAD vent PWK? is there a main difference and is it worth $250 for a new QUAD vent PWK carb over the DUAL vent?

the quad vent is meant to prevent bogging after jumps, it has nothing to do with how the bike comes into the powerband. if youre not bogging after jumps now, then no, its not worth $250.

[JB-250]

2001 cr250

 

vforce 3 reed

fatty w/ turbine core silencer

pwk DUAL vent 

 

 

I havent jumped it yet to see but i guess that there is no performance differnces between the 2 other than the bogging?

Edited October 23, 2013 by JB-250

[Curt026]

What are your current jets and what temp/elevation? Also what size pwk is it?

[mynewcr250]

2001 cr250

 

vforce 3 reed

fatty w/ turbine core silencer

pwk DUAL vent 

 

 

I havent jumped it yet to see but i guess that there is no performance differnces between the 2 other than the bogging?

there may be some performance differences, i dont know, i highly doubt it, but, like i said, the 2 extra vents are only for 1 purpose and thats to prevent bogging from the fuel plugging the vents after jumps.

[JB-250]

Would i only notice the bogging after the "big" jumps?

 

 

 

Im at around 800 elevation with temps varying from 65-80; not sure on current jets but i have tried with slide # 6 and 7 which i cant tell which is better in what areas though; will report back with jets 

 

 

 

 

size is just standard 38 i beleive as i cant fit a 39 can i?

[mynewcr250]

use this to start.

 

#7

45pj

a715 needle (stock 00 needle) on clip 2 or 1370dka or 1368dka (99 cr250) needle on 2-3

172-175 main

 

you need to verify your PV is working properly and isnt stuck open.

Edited October 23, 2013 by mynewcr250

[JB-250]

Powervalve being stuck open is what i was 1st anticipating and i wanted to check it tomorrow

 

 

 

I will try what you said as well tomorrow; thank you 

[Easy P]

HELP!!

Just installed a pwk 40 mm on xr400Bg bore. The idle is very high. Slack cable. Slide all the way down. Only one adj screw. 3 turns out. Carb came with two jets and a spring with another screw with a small black knob?  Maybe one or more of  these parts need to be installed?  Carb came with nothing not even a fortune cookie? 

[DEATH_INC.]

On 9/26/2022 at 5:04 PM, Paul Heiderich said:

HELP!!

Just installed a pwk 40 mm on xr400Bg bore. The idle is very high. Slack cable. Slide all the way down. Only one adj screw. 3 turns out. Carb came with two jets and a spring with another screw with a small black knob?  Maybe one or more of  these parts need to be installed?  Carb came with nothing not even a fortune cookie? 

Is this the PWK two stroke carb you're talking about? It should have 2 screws, 1 that holds the slide up for idle speed, and one for mixture.

You can see them clearly in this pic with the blue dots beside them. Idle top with the spring on it and the air mixture screw lower down.

 

Edited September 30, 2022 by DEATH_INC.