Keihin flatslide PWK carburetor, oppinions, issues?

Could somebody confirm the product number for the JJK, JJM needles? I think I they were 017-188, 017-182. Mrriggs, did you order direct from the sudco site?
 
The Sudco part numbers are 017-189 for the JJK, and 017-630 for the JJM.

I ordered mine direct from Sudco. They don't have a shopping cart thing on their site, you have to give them a call. 800-998-3529
 
I installed the JBM carb boots last night. They look like nice parts but are a little big for the PWKs. I really had to crank down on the clamps to get them to grab on.

While I had the carbs off, I pulled them completely apart and lapped the slides with some garnet lapping compound. Before lapping them, I moved the slide by hand and could feel the ridge that was causing the right slide to stick. I worked the right slide for hours and could not get an even finish on it because it is so poorly cast. After wearing through the chrome and copper base coat in several places I decided to call it good. It will never be right but at least it slides freely now without catching on anything.

lapslide1.jpg


The left slide was a better casting (still not great) and took much less time. I probably should have done a little more on the left one but my finger tips were killing me after doing the other one. It wasn't ever sticking like the right one so I'm sure it too is good enough.

lapslide2.jpg


It's still too early to fire the bike up so I don't know yet how well this is going to work out. I'm hopeful that since I felt a ridge before and don't feel it now, that the sticky slide issue is finally resolved. If not, the only other solution I can think of is to cough up the $130 for two genuine Keihin slides. Or for the same amount of money I could buy 14 more slides from Mike's and hope that there are at least two good ones in the bunch.
poke.gif


I've also gone up a couple more sizes on the jet needles. When I started tuning this thing it was still winter and the temperature was in the 30's and 40's. As the weather has warmed up, the bike has been running richer. I may end up having to buy slides anyway just to get a different cutout. I'm on the second largest jet needle now and the weather is only in the 60's and 70's.
 
I fired it up today and am quite pleased. It started just as easily as ever, and was a cinch to synchronize. After syncing the carbs with mercury sticks I hooked up the handlebar mounted dual gauge and went for a ride. Not only was it easy to sync, but it is holding a sync better than it ever has. Best of all, there wasn't a single symptom of sticking slides. I'm trying not to get my hopes up as this isn't the first time I thought I licked it, only to have it come back a couple days later.

It feels far different this time. The motor is more responsive to any input of the throttle [on or off] and the JJQ needles give the crispest off idle transition yet. If it'll just stay running like this then I will say that the carbs are finally done. All it took was $614.68 and countless hours over a two month period.
 
So mrriggs, what's your final setup on these carbs then? I'm still having a hell of a time getting these dialed in. I'm running a 40 slow jet and a 125 main jet. Took it out for a short ride last night and at WOT I'm still choking out badly and had to limp the bike home. Wouldn't run right after a couple of WOT blasts. I'm almost ready to go back to my old BS34's at this point.

For some reason the 19mm float setting is causing overflow on my left side, but not on the right. Can't figure that one out either. Looks like you're quickly becoming the "guru" on these "performance" carbs.
 
Right now I'm at #40 slow jet, #125 main, JJQ needle with clip in #4 slot, air screws 1-1/4 turns out.

Is your bike flooding out at WOT or when you let off? My bike pulls cleanly all the way up to WOT. If I hold it there it runs well, but when I let off it gets a bit blubbery and takes a few seconds to clear out.

The overflow problem may just be crap stuck in the needle. Also, make sure your float isn't rubbing on anything like the overflow tube. With the carb off the bike, and empty, I hold it up to my ear and flip it over. If you don't hear the float flopping around inside then it is hanging up on something.
 
To be honest, I didn't check the plugs after last night's run so I'm not sure if it's flooding or running lean. I checked them after the previous run, and am showing a little lean on the left side, and rich on the right. Not sure why. Float settings are identical and moving freely, jets are identical, air screws identical at 1.5 turns (been playing with these settings individually and checking plugs), and carbs are synced. I was thinking I may have gotten some crud in the carbs so I threw a fuel filter in line last night, but it got to late to pull the carbs off again to hose them down with some carb cleaner.
 
Just thought that I would jump in here and say that this carb thread has been the best I have read. Just data no attitudes or bad temper flare ups, nice to see. Another tip of the hat going out to Riggs for the great deal on the rephase cam I just bought from you off of eBay. Great deal. I am new here and I am loving it.
 
thedocta said:
Just thought that I would jump in here and say that this carb thread has been the best I have read. Just data no attitudes or bad temper flare ups, nice to see. Another tip of the hat going out to Riggs for the great deal on the rephase cam I just bought from you off of eBay. Great deal. I am new here and I am loving it.
Click to expand...

I agree 100%!

But the real question, Mr. Rigs is: After all of this work you have done (which I thank you for posting) have you noticed a considerable upgrade in performance vs. the previous stock carbs?

There is some great information here, and after reading everything, I'm probably going to opt for the VM carbs for my big bore motor build and I would like to do a similar write up as I find these very informative.

Thanks again for all of your hard work and keeping this thread up to date!:thumbsup:
 
Patches said:
But the real question, Mr. Rigs is: After all of this work you have done (which I thank you for posting) have you noticed a considerable upgrade in performance vs. the previous stock carbs?
Click to expand...

Most definitely. I messed with the stock carbs for years and never got them working even half as well as these PUKEs run now. The throttle response is amazing.

The best part about these is the simplicity. There are only a handful of parts and they are all accessible without pulling the carbs off of the motor. I don't even have to pull the tank or anything. Very easy to work on.

My only complaint with this whole ordeal is how poorly the carbs [and all the other parts that came with them] were manufactured. Typical of most Chinese products these days, you are basically just buying a pile of parts, not a working product. Once you have the pile of parts it is up to you to spend hours upon hours browsing message boards, blogs, and youtube videos to figure out how to make it do what it is you bought it to do.
 
ive heard rumor that these carbs are a chinese knock off. from the person i heard this from, id tend to believe him. though it is possible they are legit. these tempted me for a bit, but ill stick with my round slides.
 
If these are in fact genuine Keihins (I doubt they are) then there would be no point wasting your money on the genuine article. You can get any number of Chinese knockoffs of similarly poor build quality for $15-$75 each.
 
MrRiggs, I want to congratulate you on somewhat sorting these carbs. I'll admit that @ $299 a set, I was even tempted to buy a set. Boy, am I glad I didn't bite into that rotten apple. Honestly, for the money spent, I would just buy the Delortos. That's a real good, honest carb, not hard to tune, and not made anywhere else but Italy as far as I know.
 
5twins said:
MrRiggs, I want to congratulate you on somewhat sorting these carbs. I'll admit that @ $299 a set, I was even tempted to buy a set. Boy, am I glad I didn't bite into that rotten apple. Honestly, for the money spent, I would just buy the Delortos. That's a real good, honest carb, not hard to tune, and not made anywhere else but Italy as far as I know.
Click to expand...

That's what I'm running :D
 
Jimmy, even though I couldn't quite put my finger on it, I knew there was a reason I liked you, lol.
 
If it was work, I'd be paid, lol. No this is just S&Gs ..... and hopefully helpful to some. I hate to see good bikes down troddin upon. I know it's inevitable in some cases and with some bikes but with the 650, there's such a vast knowledge base available, nobody has an excuse for fucking one up ..... really, I mean this.
 

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