Topic: CB650 CV head ALTERNATE carbs!!(w/kawa GPZ600 isolators fits '79/80 heads too!)

[Soos]

They must have a aftermarket stage 1 or 3 kit then.
The jet needle had  6  slots for the jet needle clip to be adjusted to.

StrongPerf you wouldn't by chance know what a stock jet would be for these carbs would you?


l8r

[StrongPerf]

They must have a aftermarket stage 1 or 3 kit then.
The jet needle had  6  slots for the jet needle clip to be adjusted to.

StrongPerf you wouldn't by chance know what a stock jet would be for these carbs would you?


l8r

They did have jet kits. I removed the plugs just like MRieck said.

The do have 6 slots but each slot is probably about 1mm adjustment. You can use the .5mm washer as a half adjustment. Mine needed it as 1 posit was slightly lean and the other slightly rich. The 1/2 adjustment hit the spot.

Sorry I do not know what the stock jetting was. I'm sure a GPZ board search could tell you. You might also look at Dynojet or Factry pro's web sight and look at what jets are included in thier stage 1 and 3 jet kits and assume stock was slightly lower.

Either way your airbox and motor are different. Start with WOT runs and adjust the main first.

Factory Pro has a good instruction on tuning CV carbs on thier web sight.

Good Luck!

[Soos]

Update on the carbs....
I have done a bit of fiddling with jets, and had a minor oddity, but things are working well.
The jets in the ninja carbs had a shorter head to them than the jets I have(for the cb650)

Sooo.....   Found things were lean, and figured what the heck. they will probably run richer than the correct jets with the shorter head, but I could find a happy medium somewhere... I got enough jets.

When running with 115's seemed pertty good, but went with 120's.
Plugs look ok if anything a hair rich.
The jet needle ended up positioned 1 clip from the richest setting as well.
Idle jet screw position is unchanged though.



Have been avoiding the trickle charger, and the sub 30 degree mornings, she still starts great now.

That starter circuit is imperative to clean on these IMO.

Takes separating the carbs, but these carbs are a LOT easier to deal with than cb650 carbs.
I'm anticipating doing a port job on a CV cb650 head to drop these onto.


l8r

[Ecosse]

Good news Soos. This swap is fascinating and look forward, as I'm sure you are, to a road test.

[Soos]

Good news Soos. This swap is fascinating and look forward, as I'm sure you are, to a road test.

I have been riding when I can this year.
About 200 miles now.
Nothing but smiles.

I really like the "stupid proofing" of the throttle position with CV carbs.
Still not liking the throttle cable though. no room to take up any more slack, and the cable is loose. Thinking of just calling Z1 and asking if he has anything in stock that will work.(based on measurements of cable used, and what I need)
Something will present itself eventually for a proper fit there though.


l8r

[bert96]

Just for information,

I bought CV carb from a cb700 nighthawk(for my 750 k4).I have been told that diaphragm are not available anymore from Honda    i don't know if it's the same thing for Kawa....


Bert

[Soos]

Actually thats something I have not looked into.

I have found a few rebuild kits, and a few dyna stage 3 kits on E-bay but haven't looked too much.
Didn't (thankfully) have to do much.
The 2 things I have replaced are the main jets, and the float needled.

Already had the jets, and the needles were like 10 bucks or so.


Always wanted to know if those 700cc carbs lined up with the SOHC cb750 intakes.
How do they compare to a stocker set of carbs?



l8r

[bert96]

Here's what low-side said about these carbs.

''I found something neat the other day that surprised me that it worked so well.  A set of carbs off of an '84-'86 Honda CB700 have exactly the same spacing as the stock carbs for the 750.  It took a lot of force, but I mounted them by getting the stock boots up to temp. by riding the bike, removing the stock carbs, lubing up the CB700 carbs, and just pushing them on.  The stock pull cable hooks right up, the push cable jacket needs shortened about 1 1/4", and you need to make a bracket for your new choke cable.  It was simple, cheap, and the carbs are 33 or 34mm so they flow great''.


I bought my carbs on ebay this winter  and i did not get the chance to work on my bike yet,but as low-side said it should fit straight in.

[CBR954AD]

Hi, i just found this post,
I am having huge issues with my stock carbs off my 79 CB650. I fully rebuild motor, with new piston rings, and complete gasket kit, also stage 1 port polish head work. as far as carbs, they are fully rebuild with new gskets, and jets. once I installed the carbs it was very hard for bike to start. I am also running air pods, and dime city 12 inch short mufflers, pretty much straight pipe. so carbs are running really lean. i open carbs and shimmed needle, also pilot air screw is set to 1 5/8 . and have sync. after doing all this, bike starts right away and idles great at 105 rpm, however when i rev up. and release throttle the revs stay up. (no its not cable issues, throttle valves return to close position. the only way to lower back the rpm is kill engine or lower rpm from idle stop screw.
so I got another set of carbs from my friend off a 91 CBR600RR. they are same size and main jets are 105. only issue is the carburetor do not line up with the intake runners. on carb 3 and 4 they line up fine, but 1 and 2 are off by like 2 mm. just to see if they work, i used rubber flex hose. and the bike fired up better then my carbs, and engine was revving freely and idling back down.
What can I do tio make this bolt on, which intake runners to use?

[Scott S]

 Check to make sure the pods aren't covering the kidney bean shaped intake passage on the throat of the carbs.

 I used K&N dual style air cleaners on CV CB650 carbs and they worked great.

[CBR954AD]

ya they are not covering the passage, I believe that is  part of the low speed circuit