Vm28ss vs 28sc ?!

All right, and does the carbs will fit under my fuel tank, without relocate my Gas key?! I know that the gas key on Kz1000 are behind the first carbs.. the 750 are in the front on the Cv carbs ?!!

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The only VM28SS carbs without a pump that I know of were used on the '78 Z1R.  The big Suzukis may have also used 28 non pumpers but I have no knowledge of the Suzukis other than they usually had both air/fuel screws AND pilot adjusters.




 

Yes ! Non of the  VM26 or VM28 Mikunis fitted to the GS's as stock ( including the VM32's as fitted to the GSX1000S Katana) ever had accelerator pumps and all had both fuel and air screws present.
As for the pumper 28's on KZ's.
This only applies mostly to US equipped machines to help comply with the emmisions laws..
Other countries didn't have the strict emmisions laws to contend with so didn't get pumpers on any KZ model that was originally destined for their market.


 

Interesting...I wasn't aware non-pumpers were used outside of N America.  But I doubt many used sets entered NA over the decades.  Good to know that Suzuki used non-pumpers.

Kawasaki went through a number of carb iterations in the 70's to comply with emissions regs.  The first change was switching to 26 mm.  After a couple of years that wasn't good enough.  The main issue was high emissions at idle, which required leaning out the fuel mixture so much that the big bikes developed a hesitation when starting from a full stop.  The solution was to add a pump to give a small shot of gas as the throttle was initially twisted.  The first carbs with a pump were 26's, but they were so hard to set up that KHI upsized in mid year to 28's with a pump.  I had the 28 mm pumpers on my 1980 KZ1000 LTD, and they were OK, but I had a spare set of 26 mm non-pumpers that I put on because they are so easy to set up and are very stable.  I love them!

Max, I didn't realize you were modifying your engine.  Keep posting on your results please.

Thank you, I appreciate!! Yes I can’t wait to put this bike on dyno!! I don’t know what numbers it supposed to have!! My fear is the gasket kit I’ve put in it!! I wanted Cometic gasket but they were not available for these old bike!! So I’ve bought ebay gasket kit (vesrah) (cartoon gasket).. I have make 800km.
now I will retorque the engine before the Dyno this summer!! Cross fingers

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Interesting...I wasn't aware non-pumpers were used outside of N America.  But I doubt many used sets entered NA over the decades.  Good to know that Suzuki used non-pumpers.




 

Up until about 15 -20 years ago we'd barely even seen a set of vm pumpers until the resurgence in popularity of these bikes boosted the US to UK import market to cater for the spares demand.
I've quite a few sets of both Kawa and Suzuki VM's waiting for attention when i get the time .
Some of which can be seen lurking on the wall in the background of this recent pic.
I favore the vm26 bodies for when i'm boring them out to 30mm ( they have a fractionally thicker casting on the boot side stub compared to 28's ) and the horrid 26mm pumpers can be made to work well once you disable the sensor diaphragm and plug the drilling.

My last question!!!! Does the fuel tank petcock will need to be relocated?! I see that kz1000 has the petcock behing the carbs!! Mine kz750e1 has his petcock just behind the head cover, before the begeniing of the carbs!!!?? Does the VM and CV have the similar height?!