Dual Kehin PWK 32mm flatslides question

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I have the toming sorted now and I will today be messing with the flatslides for a bit. I have them in and the cable routing slack sorted but I have been messing with timing and other stuff so havent gotton to the adjusting or anything of the carbs.

Before installing them I adjusted the idle screw so .010 gap shows from the slide towards the front

I fit them with the cable routing just under the top bar and used the barnett junction box insteda of that plastic one.

I have the lines ran like Jim has with the pingel filter under the units etc.

I started it up yesterday and its only idling when choke is on. I havent messed with the air screws or floats or needle yet.

Anything obvious going on? I dont want to take them off to clean pilot jets or anything if I dont have to.

Dual Kehin PWK 32mm flatslides question


Cheers!
 
two years with those flat slides here

you need to simply raise the slides to get a faster idle, forget the .01 gap stuff, slides higher, I like mine around 1200rpm when warm

turn the knurled idle screws in clockwise on each carb to lift the slides until you have higher idle you want

the airscrews, in for richer, out for leaner, should both be cracked just a very little bit open from fully closed
as in about 1/8 of a turn out, you will know they are too far out when it starts popping on deceleration

raise the chokes only for cold starting, then immediately turn them off and use throttle to warm up a little
 
Looks good iceteanolemon, I'm a little jealous of you guys since I bought the single version from JS, but it's going to fit my application better (no WOT yet, bike isn't ready for it) and it hit my wallet less. But one day I'll get 'um, so interested in your thread. Cj
 
If PWK's have similar, almost universal best idle air screw out base line designed as 1.5 turns, then diddle float level to set the base line fuel feed for idle to WOT. Ask vendor or manufacturer what the idle pilot screw is expected to land on. Can work pretty dang well just compensating by idle screw, but I've had hard to impossible to adj idle cases that worked a treat after float set by idle screw turns, rather than just crude get ya started physical fuel or float measure methods.
After happy with this then the secondary methods already listed are set to best use. Can never forget about air leaks and initial spark timing of course.
 
If PWK's have similar, almost universal best idle air screw out base line designed as 1.5 turns,

no, they do not

the air jet needle is faster tapered, again the recommended setting is around 1/8 turn out from fully seated
 
OK thanks for the tips. I was going to go for the single as well but I had a single amal and it was bugging me so I did a impulse purchase and got the duals.

Actually the real story is I was at my dads house and he was showing me his 68 Triumph Bonneville 650 and The dual carbs on that thing look awesome. Especially with the tank contour vs the manifold having a slight pitch to push the carbs out the sides. Then I mention it to my wife and she purt in the order for me! :shock: :D

The Amal was working nicely though but I read so much about better top end and I like the complicated nature of having dual carbs too. More factors for failure!

Now I have them in and have been messing with the idle a bit and it starts so easy and has the ability to idle at extremely low rpm. The throttle response is very quick vs the old Amal too. I have only took it down the street and back a few times so I dont know how the top end is going to work out yet. Today it is unusually humid so I may have to run it up the street further and see how it goes in the top end.

Of course I am spending some time staring at it while im here in the garage!



Dual Kehin PWK 32mm flatslides question


I am noticing the cable wants to unseat from the copper adjuster on top of the carb too. I grabbed them and pulled the cable back down twice to reseat fully into the carb.
 
beautiful fuel hose set up

I think you are going to love their performance all through the rev range
 
1up3down said:
beautiful fuel hose set up

I think you are going to love their performance all through the rev range

Thanks! I got the setup from JS!! The equipment came totally complete and with instructions and all the gear needed for installing. This by far was a comprehensive kit with everything looking good. The modification to the inner airscrew is handy as well with the 2"adjustment bar. The emgo filters look good and fit perfect. The only thing that bugged me was the junction box, that thing is a little flimsy, I guess it probably does the trick but I had some type of premenition that down the road it was gonna have a failure or something. The Barnett one from old brits was cheap and made of alloy, I think I feel better knowing thats under the tank instead. If I had a pic I would post but I already got it installed under the tank and I am lazy.

I think I already posted the pic of the setup when I got it in the mail on an earlier thread.
motorsport-kehin-flatslides-t13609-30.html


The cream on top was the clamps. I bought some clamps that were the wrong size for something else and noticed them sitting on the counter. Low and behold they fit perfect.

Here's the clamps I am using. Stainless crimp I got a box of 25 or something. I intend on getting some for the oil lines too. (ill keep a few screw on ones in the tool bag for temp fixes but I cant stand looking at those things. they remind me of the jery rig fixes I do on household dishwashers and washing machines!

grainger item # 16700007
Dual Kehin PWK 32mm flatslides question



Now I need a better hose barb than the one piece that I have coming off of the petcock. This one requres me to remove the clamp and hose when removing the tank :( I tried looking at my local hardware store and such but nobody around here stocks a separate barb to the threaded portion "compression?" fitted one...
 
Looks like a nice setup. My experience with that reinforced fuel line is that it will be hard as a rock in a month or two. When you go to move it (as in taking off the tank) it may start leaking. I just switched over to yellow Tygon. It is not exactly "vintage" looking by any stretch but it stays very very flexible and no clamps needed. I did get some smaller diameter brass ferrules which make it look a little better. Well, I don't do shows.

Let us know how it goes once you can crank it on.

How close is the fuel line to the cylinder barrel? Looks too close from the picture.

Russ
 
batrider said:
Looks like a nice setup. My experience with that reinforced fuel line is that it will be hard as a rock in a month or two. When you go to move it (as in taking off the tank) it may start leaking. I just switched over to yellow Tygon. It is not exactly "vintage" looking by any stretch but it stays very very flexible and no clamps needed. I did get some smaller diameter brass ferrules which make it look a little better. Well, I don't do shows.

Let us know how it goes once you can crank it on.

How close is the fuel line to the cylinder barrel? Looks too close from the picture.

Russ

Its about an inch away, should I bring it back a bit more? I guess it might be a good idea! Nobody wants to see a thread "oh man I roasted my commando" tomorrow....

My old fuel lines are yellow and solid as a rock! But they don't leak though. I am going to need to move the needles, when running it up and down the street cruising it misses here and there. I have the idle and mixture screws within spec though.
 
Stop staring at it and get on with it and just ride, you can look at your bike anytime, you will be very happy with them carbies, I don't know about having them fuel lines sitting below the carbies could be asking for air locks in the lines, I run my fuel lines straight down to the carbies all down hill run, enjoy your new found performance.

Ashley
 
iceteanolemon said:
I just switched over to yellow Tygon.

My old fuel lines are yellow and solid as a rock! But they don't leak though. I am going to need to move the needles, when running it up and down the street cruising it misses here and there. I have the idle and mixture screws within spec though.

If it misses while cruizing its running rich. Probably need to the raise the needle clip a notch.

I used to provide tygon fuel line but it was a little loose - it needs to be 6mm to fit the carb best. Hard to find tygon in 6mm thick wall that doesn't kink.
 
fuel lines look just fine

no worries about being too long as they suck fully when started so no bubble issues

an inch away is fine, leave it, air flows in there so no overheating of fuel line

congrats

don't get the occasional misfire, I would not immediately assume carb jetting, suspect something electrical,
check plugs they may be partially fouled from early air screw settings, typical, check timing with strobe light,
and thirdly take fuel lines off tank and open pet cocks into a cup to see if they flow gas strongly, could be partically blocked and starving for fuel. Only if all checks out ok then suspect carb settings, although they ought to be perfectly jetted from Jim, we just put two new sets on Commandos and no jetting changes needed
John
 
about the misfire

open gas tank filler cap while riding and see if misfire goes away

if so, you may have the air vent in the cap plugged with some stuff, run a wire through it anyway to check
 
1up3down said:
about the misfire

open gas tank filler cap while riding and see if misfire goes away

if so, you may have the air vent in the cap plugged with some stuff, run a wire through it anyway to check

The petcocks seem to be sending fuel OK, The timing I fought with for a while and confirmed to get it timed right to the 28 degrees. I now will check again though since you brought it up I am going to place some other plugs back in and try again.

I went to buy some new NGK's to replace the ones I had in there but Autozone doesn't carry them anymore. "BPR6ES" instead they gave me some Bosch ones. I am starting to suspect these Bosch plugs if they are the right cross reference. matter of fact I'm pulling em now to check...

OK halfway through this post I replaced the new Bosch plugs with my old NGK's and did the test run again. Low and behold the bike isn't missing anymore. I think your right on the Bosch being fouled.

If I stand behind the bike and listen to the exhaust it sounds like the left side is not hitting on every fire. Funny thing was going downhill was fine and smooth but coming back up it would buck and miss. Then I put the old NGK's in and the thing is pretty smooth coming back. A total difference.

Now the I have the idle not returning to 1000 right away, its staying up at around 1300 for a bit (15 seconds) before settling down to 1000.

Also I have an issue withe the cable ends to the carb getting stuck above the copper fitting a few times when the bike is in an high vibration idle. One of the cables will get lodged up and until I manually reach down there and fix it the bike will surge up in rpm. I need to devise a solution for that one so I don't get irritated with that on the road.

For reference the Bosch is a "super plus WR7DC+"...

Dual Kehin PWK 32mm flatslides question
 
Ok, good report, seems those old plugs were the problem

and you are "ok" in using the new NGK BP6es because that is only one heat range "warmer" than the prescribed 7ES,
just fine around for 30 mile loops but much longer the 7's

Ok now to the idle hanging up and not coming down right away

This is because your air screws are still too far turned out, too lean causes not settling down so turn those little babies in some more until it settles down, and then see if you need to further adjust your slide stop knurled screws

and on to the lower throttle cables pulling up out of their carb holders: ya gotta find a way to keep backward pulling pressure on those lower cables to keep them in the holders, maybe take tank off and duc tape the lowers kind or backward pulling to the big frame tube or something, also maybe wrap some duc tape on the cables right above where they go in the carbies and them pull them down and wrap the remaining duc tape around the carbs to hold them?

you are getting there!
 
iceteanolemon said:
I went to buy some new NGK's to replace the ones I had in there but Autozone doesn't carry them anymore. "BPR6ES" instead they gave me some Bosch ones. I am starting to suspect these Bosch plugs if they are the right cross reference. matter of fact I'm pulling em now to check...

For reference the Bosch is a "super plus WR7DC+"...

http://www.sparkplugs.co.uk/pages/techn ... ss-ref.htm

BPR6ES = WR7DC
 
have been running Bosch for a long time now with no problems at all. don't know what # without going out to the garage and checking. Went to those plugs as they are available at all chinese auto part stores, thinking I could replace at will, but have never had to . Don
 
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