PWK 39 jetting question

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Cody19670001
Posts: 15
Joined: October 20th, 2013, 11:39 am

PWK 39 jetting question

Post by Cody19670001 »

I just bought a PWK 39 from Sudco who says they are going to send it with their recommended jets in it. I have an FMF Gnarly with their Turbine Core muffler, on a stock motor 89 mm piston and no porting. I have been running the old PJ Carb with:

175 Main
55 Pilot
Stock 1368 needle
2nd Clip
2 turns out on the air screw
700 feet above sea level
30 to 50% humidity
14 oz flywheel weight
Pro X cast piston


This has been a good setting on the old PJ for Tulsa, Ok.

I'm probably nuts for taking off a carb that seems to be set up pretty well. I've just read all the posts about the night and day difference that the PWK 39 offers. I know Sudco is going to put their jet set up in it, what ever that is. Does any one have a recommendation?? Am I making a mistake making the change?
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other
Posts: 338
Joined: January 25th, 2010, 5:11 am
Location: Perth Hills, Western Australia

Post by other »

Yep, I recommend you ditch the Sudco 'recommended' jetting before you even try to run the bike ! It will come with a 60 pilot and 160 main. It blubs like a bitch off the bottom, and will seize as soon as you pass half revs under load, it's EVIL lean !
170 main (172 in soft dune sand)
55 pilot (can handle a 52, or even a 50, but I like the softer hit off the bottom from the 55)
Sudco needle is OK, but clip it up to second from bottom, or stick with your 1368.
Cut about 2 and a half coils off the idle screw spring so you can screw it in far enough to idle . . . .
and that should give you a half decent baseline to start tuning from . . . .
Once it's done right, the PWK is night and day better than the PJ . . . . .
o.t.h.e.r . . . . .Over The Hill Enduro Rider
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hoofarted
Posts: 2628
Joined: July 2nd, 2007, 8:48 am
Location: Rancho Cucamonga, CA

Post by hoofarted »

I plan on doing the same thing. Still running on a well-jetted PJ with the DGN needle. The settings I have been recommended are: DGN needle 172 main, 45 pilot. all at about 2500ft. Good luck and post your results!
The CR500 is an acquired taste. If you don't like it, acquire some taste...

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Cody19670001
Posts: 15
Joined: October 20th, 2013, 11:39 am

Post by Cody19670001 »

I really appreciate the advice. On the DGN needle, any thoughts on starting clip position??

Thank you very much
Homeskillet
Posts: 11
Joined: August 14th, 2012, 4:34 am

Post by Homeskillet »

Extended air-screw. That big carb can be a finicky bitch off-idle.
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jar944
Posts: 57
Joined: August 12th, 2009, 7:15 am

Post by jar944 »

The DGN was extremely lean on the straight diameter for me.

I'm running a DGK, 38 pilot, 175main & #6 slide.

@ 400-2000' elevation
vito.a
Posts: 49
Joined: September 16th, 2013, 10:15 am
Location: Tucson/Edwards AFB

Post by vito.a »

You guys need to borrow a PWK Air Striker. It will completely change your bike!
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