Ninja EX500 carbs on an XS650?

Lmao u were right , I wasn't even thinking about that. It was pulled a little tight. Yesterday i was doing some wiring and must have pulled the cable and caused the problem.

Thanks for the help.
 
Hey I need a little help. My set up is 700 big bore kit, open exhaust and, air pods, +30 above sea level. I'm running 140, 38, jjj on 3 clip, and mixture is 2 turns out. I'm running a little rich and want to lean it out some. How do I do this.
 
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Where is it rich, Idle, top end or midrange? Depending on where it rich is where you make changes.
The carb guide ha a "Tuning For Mods" section. Yes the carb guide is for the stock carbs but the same basic principles apply.
Start with the WOT testing to get the mains right, then do the midrange testing to get the needle right, then do the idle testing to get the pilots right.
Leo
 
I am also having continuous stumble with these carbs while just cruising with the throttle cracked open probably 1/8-1/4.

Would this be solved by adjusting the mix screws?

I have the pamco unit so dead cylinder is out.

I tried doing it by putting the rpms at around 1k and adjusting the screws but the rpms barley changed , by ear that is I dont have a tach.

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Dead cylinder is fine with Pamco you just need to have a grounded spark plug on the wire you have off.
 
a bit hard to tell from here but if the slides are open, bump the pilot or raise the needle a slot (are the replacement needles adjustable?) My set of these is still in the box I bought them in LOL.
 
a bit hard to tell from here but if thw lsides are open pilot or raise the needle a slot (are the replacement needles adjustable?) My set of these is still in the box I bought them in LOL.

Yeah im using the JJJ needles , I changed the clip position from 3-4-5 it occurred at all positions pretty much the same.

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What air filters are you using? The K&N style pleated filters, the shorter and more oval the more the effect. the longer straighter the less the effect.
This style of air filter cause too much turbulence in the air flow through the carbs, this causes poor slide lift. This causes the issues you have. Tuning can minimize this effect but not get rid of it.
On my 75 I spent weeks trying to tune out this issue with my stock carbs. Read on here about the pleated filters and how they did this. The recommendation was to replace with the straight foam filters, Uni-Filters by brand. This eliminated the issue.
So if you are using the pleated K&N style filters swap them out for foam.
Leo
 
I'm not a carb guru but I do have a little common sense. Here is the problem I am now having and it has me stumped. The bike starts 1st kick every time and runs like a top, but after the bike is warm the Rpms are dropping them the bike will stall out. I have had these Damn carbs off at least 10 times and I have checked (float height, needle postion, air leaks) them and cleaned them before I put them back on. These carbs are very promising but I can't figure this issue out. I have looked at the float needles and they seem to be in good working order also, but I'm losing gas if it sits to long ( I have clear fuel lines). :banghead:
Someone please tell me how to determine if the float needle aren't seated properly. All signs lead to this being the problem.

Could it be that I put the needle floats on the tang backwards
 
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Raise your idle speed, recommended idle is 1200rpm I believe.

From what I understand and from what I'm told here is that adjusting your idle a couple times during the warm up and changing temperatures is pretty normal and expected. A lot of people have pieces of rubber on their BS34 adjusters to make adjusting idle easier while riding.

With the CVK34 it's a little trickier as you have to reach down under them, I do it pretty regularly at stop lights.

Also, what do you mean you're losing gas? Do you mean it's leaking? Do you turn off your petcock when not riding on your '72? float needles are not designed to stop fuel for prolonged amounts of time, they are designed to regulate fuel.
 
I have the problem figured out. I had a homemade bracket bolted to my carb top and one of the screws was too short and it was letting air in. I got it running and idling like a mad ape...... Then I had the scare of my life. It started dying again after I had it back in to the house, but I quickly figured out that it was very low on fuel... I need to figure out a way to gauge my fuel.
 
I've been running CVK34s for the last season and this year as well, love them. However I lost the left mixture screw last year. I bought a K&L rebuild pack that came along with amongst other parts a new mixture screw, I screwed it in and off I went.

I noticed however that the left cylinder stumbles a little bit at idle and the mixture screw has no effect at all, however the right screw does. Anyone have any experience with 3rd party mixture screws? I've been looking to replace it, apparently there are idle screws aimed at the harley crowd that are actually thumb screws which I think are cool.

http://www.ebay.ca/itm/idle-mixture...552344?hash=item5b14f3e5d8:g:0a8AAOSw~gRVxuJT
 
Something I learned today: The plastic needle holder is indexed!

I had this strange stumble / hesitation when cruising at part throttle around 3000 - 3500 RPM. Eventually I removed the slides and noticed that one of the five "legs" of the needle holder was blocking the slide hole. Then I noticed that the slide has small notches that should align the holder. I had pushed the holder in an jammed it on the notches. It was blocking the slide hole and was not holding the needle down properly. Fixed, tested and all hesitation/stumble was gone!

Pekka
 
I believe I read that one of the carb brackets needs to be notched. Can anyone tell me where to do this, the motor is not in the bike yet so it is hard to figure it out. A pic would be perfect. thanks tim
 
Thank you to every one on this thread. I've fitted a set of mint CVK's off a GPZ500 that I got cheap off Ebay. I finally got every thing else I needed today and slapped it all together and guess what? She fired up first kick. Just needed the mixture screws turning out a bit and she ticked over like a goodun. I'm still in the dry build stage so can't take her for a spin, but I can tell she's not so far off right just by revving her up static.
I'll briefly list my set up.
Ignition and electrics by Electrex world
Exhaust straight through from original headers
Carbs 34mm Keihin CVK, 38 pilot, 140 main, 46-jjj needles, 2x needle clips on middle groove. From Allen performance
K&N pod filter's
34mm inlet rubbers. From Yambits
I put a notch in the carb bracket to miss the frame and used a choke lever off a British bike mounted on the handlebars to operate the enrichener
Must now crack on with the rest of the build I guess Haha
 
Or a dollop of axle?
Now cut that out WER! No grease on diaphragms! If anything a touch of pure silicone like dielectric silicone, yeah it's expensive, but cheaper than a new diaphragm. There's a trick with "shrunk" diaphragms and working the cap just so to get it back down with the diaphragm in the groove. You'll get there.
 
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