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Carb question/identification.

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28 Jan 2022 12:54 - 28 Jan 2022 18:13 #861258 by epiphalactic
Carb question/identification. was created by epiphalactic
Hey everyone.  So a little back story and context. A couple years ago, a buddy gave me his old kz that he was going to work on.  It's a 1977 kz650b I believe, based on the paperwork and title.  It's a full and complete rebuild I'm doing,  from the ground up. It had most all of the parts, and the last time it was put together which was about 4 years ago, it wpuld run decently, but it was having carb issues. So obviously based on that the bike came in pieces, and I know I'm going to have to purchase quite a lot to get this up and running, but this whole situation is going to be more of a learning experience, and I will probably never get rid of the bike once it's done.    I've never done something like this, but the bike was free and I'm using this as a kind of, intro, into engines.  I am pretty mechanically inclined, but forgive me if I don't know the names of stuff, or how to begin identifying.  So the bike came with two sets of carbs.  The ones installed (loosely, lol)   were ribbed. (Pictured). I'm thinking they were the classic vm24s as they did not have the extra port at about 10:00 though they do have three ports so, maybe I misunderstood something.  The set I need identified, description and context:  The second set of carbs that came with it, had a smooth, non ribbed body,  and seemed to be identical for nearly all intents and purposes except the slide, and the bores of all the openings is larger on the smooth set, and the carb itself is slightly larger.   Other than that they look like they may be able to bolt right on, and all of the holes and everything are the same, the float bowl in the top cap piece fit onto it just fine.  ​​​​​​the previous owner had no clue what they were, or came off, all he knew was the owner before him purchased them with the intent to replace the ribbed ones.  When I opened it up,  one of the ribbed carbs is trashed as the slide was completely seized in there and no amount of work could get it out.  But the other set that came with it, the smooth, we're in quite good shape and I was able to remove the slide and get them completely broken down so that I can clean them very well.    So long story long, the identification part is, does anybody know what this smooth bodied carbs are?Questions:  What they came off of? Was it another KZ650 or was it maybe from a 750 or something?  if I get these all put together and rebuilt can I slap them on my 77?  And final question, if it is going to be a big deal or something to replace them, would it just be worth it to go get a fourth carb to make the set, of the ribbed ones?  Really all I would need is the body.  So the pictures are of the smooth bodied ones, one of the ribbed, and a couple comparing the two. 

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Last edit: 28 Jan 2022 18:13 by epiphalactic.

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28 Jan 2022 16:08 #861283 by zed1015
Replied by zed1015 on topic Carb question/identification.
Non of your pic or links are visible but all the ribbed carbs will be Z650 and either VM22 or VM24's.
Then non ribbed will be VM26 or VM28's and are from either Z900/1000 or GS750/1000 depending on mixture screw configuration or even VM29 smoothbores which are performance carbs and never fitted as stock to any machine. 
The 26/28's are the same spacing as the 22/24's but will need the 900/1000 boots with a slight modification to the mounting holes to fit the 650 head.
Once you post some visible pics we can confirm what you have.

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28 Jan 2022 18:05 #861305 by epiphalactic
Replied by epiphalactic on topic Carb question/identification.
Let me fix the pics.  Thank you.  I'll assume they're vm26 then. They're only slightly bigger.  

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28 Jan 2022 18:08 - 28 Jan 2022 18:19 #861306 by epiphalactic
Replied by epiphalactic on topic Carb question/identification.
​​​​
Not sure why they aren't working. I'll try reuploading
Last edit: 28 Jan 2022 18:19 by epiphalactic. Reason: Fixed in post

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28 Jan 2022 18:17 #861307 by epiphalactic
Replied by epiphalactic on topic Carb question/identification.
I think I fixed it  

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28 Jan 2022 18:24 #861309 by Mikaw
Replied by Mikaw on topic Carb question/identification.
Zed1015 will be the expert. The body with the horizontal rids are VM24SS used on the 650. The body with only the vertical rib are VM26SS used on the Kz1000. 

Just a note of caution. The float post look very pitted and might be weakened. Support them while pushing the float pin in and out. 

1976 KZ 900 A4 kzrider.com/forum/11-projects/613548-1976-kz-900-a4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
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28 Jan 2022 18:38 #861313 by epiphalactic
Replied by epiphalactic on topic Carb question/identification.
Yeah they aren't as bad as they look in the pic but there is some pitting to it.  I had plans of being very careful. Thank you much for the caution.  
I am going to be soda blasting these clean, only in the float bowl the top bowl and the outside of it, and we'll just be using some very fine Scotch-Brite to clean up the tube on the inside, 
Are there any coatings and forgive me if this is a stupid question, but are there any coatings that may keep that (assuming) zinc from corroding more in the future?
I've heard of some people using I can't remember what it's called but it's made for inside of float bowls, it's a very thin epoxy, and I've also heard of people using another product that essentially bonds kind of a molecular way in a very thin coat to help prevent corroding. Are there any that you know of that work that you would recommend? My initial plan was to just leave them there as I've always kind of thought that would be the best idea but if there is something that can maybe protected from further pitting as these carbs are stupid expensive online and I don't want to have to buy more.  

One last question for you, sorry I know I type a lot and make long questions, there are some quote unquote universal carbs by mikuni that are the newer versions of the VM 24 and 26 etc.  Can those even maybe with a little bit of modification be used to replace these older carbs or is that a stupid question too?  

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28 Jan 2022 18:47 - 28 Jan 2022 18:49 #861314 by epiphalactic
Replied by epiphalactic on topic Carb question/identification.
No eBay APP ID and/or Cert ID defined in Kunena configurationAlso, this is for anybody that is willing to answer

, assuming they're the 26 as mentioned to mount them I'll need the 1000 boots, like so?
 The boots that went with the original carbs had the port, but I just checked again and actually all of the ports have had their nozzles blocked. So would the version of this without the port be better?   further, I'll need to mod the boot mounting holes, I'm assuming they are what a little bit closer together or. If nobody answers this before tomorrow, I will probably have already looked that up.  
 Now, I have done some reading, and I see that that is a fairly common mod to do (putting the 26s on) but I also note that quite a few people say the 24s are already kind of oversized for the 650,  and that you really want to see a performance boost without doing some bore modifications. 
Is that going to be the case? 
​​​​​Obviously, as I said, im not doing this to see performance upgrades, I'm just doing this so I can get the bike back on the road, and running well.  And is there anything besides doing bore modifications, that would allow those 26s to give me a bit more power?  
 Further, 
if I put these guys on there, would it be safe to just use the jetting of the stock vm 24ss? Or does anyone have any recommendations for what size Jets I should use to start? 
 To be honest, I just picked up one of those cheap eBay rebuild kits, and have one of the sets of mains that comes with a bunch of different sizes, on the way.  My plan was to just put most of it back together with that kit and then when it comes to tuning the bike I could mess around with the jetting, but if anybody has a good starting point that would help a lot. Finally, 
 Assuming the majority of the bike is going to go back to stock, as I had planned on keeping the air box and everything, essentially just restoring it, which I have to do anyways to get the antique tag for it on my state, would there be any other modifications or changes that I would need to make in order for these 26s and the motor to run its best, and maybe any further modifications you guys might do to a bike in my situation? As I said I'm going to be tearing the entire thing down, I'm going to just look at the gearbox but I don't know if I'll need to do anything in there it's still full of oil and last I looked at the oil it looked pretty good but.  I digress.  Since I'm going to already be in there or are there any crucial pieces you guys think I should replace anyways just being in there, I'm essentially planning on replacing any moving component, if it needs it.  The ones that I don't have to replace are going to get either sand or soda blasted depending on their location in the motor and use.  

Thanks to anybody who is reading my long-winded questions with multiple questions within them. I appreciate any answers anybody can give me whether it's just a one question or multiple.   
  
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Last edit: 28 Jan 2022 18:49 by epiphalactic.

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28 Jan 2022 20:50 - 28 Jan 2022 20:52 #861316 by Nessism
Replied by Nessism on topic Carb question/identification.
VM24's will run fine on your bike.  If you use a big bore kit then the 26's may be more appropriate.
Last edit: 28 Jan 2022 20:52 by Nessism.
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28 Jan 2022 22:20 - 28 Jan 2022 22:22 #861320 by Warren3200gt
Replied by Warren3200gt on topic Carb question/identification.
The cost and work involved in using the Vm26 will be more and will gain you nothing without performance upgrades to the head/bores/pistons. Sell them to help fund the project. 
Kawasaki put vm24's on the 650 for a reason and they know what they are doing.  So use the vm24. 
The slides in the vm24 will loosen up if you use spray carb cleaner repeatedly and let it soak in each time over a few days. DO NOT mix the internal carb parts from one body with another. It is likely the internal passageways within the carb body are blocked partially or fully. These are critical and must be clear. If you don't have specialist tools use spray carb cleaner again and ensure those passageways are clear. You do not need or want to use carb kits from ebay. Either keyster or oem mikuni part only and even then only the gaskets and o rings. Clean all the original brass parts ensuring the passages are clear. 
You don't need any coatings just ensure you use either ethanol free fuel or an ethanol stabiliser in your fuel to help prevent modern fuels fouling classic carbs.
You say the carbs were fitted loosely, the bike will never run correctly like this. The carb to boot must be an air tight seal so that the piston down stroke draws in both fuel and air in the correct mixture supplied by the carb not air from the seal which would make the delivered mixture very lean. 
 


Z1000J2 somewhat modified!

Last edit: 28 Jan 2022 22:22 by Warren3200gt.

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28 Jan 2022 23:16 #861323 by david richard
Replied by david richard on topic Carb question/identification.
hi as you asked the question about other work on the motor with it in bits the starter clutch would be a part i would look at as your there 
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29 Jan 2022 02:40 - 29 Jan 2022 02:42 #861327 by zed1015
Replied by zed1015 on topic Carb question/identification.
The ribbed carbs are VM24MM and the others are VM26MM Kawasaki carbs.
The 650 boots are too small for the vm26/28 which is why you would need the 900/1000 boots ( which also have the vac port tube) to fit them.
The holes in the 900/1000 boots are wider apart than the 650 ones so if they were to be used the holes need be elongated inwards slightly for them to fit the 650 head.
 

AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





Last edit: 29 Jan 2022 02:42 by zed1015.
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