VM carb differences

[Jeff Abgrund]

My 1978 GS750 came with pods when I got it a few years ago. When I was going over the bike I noticed that the #3 Pilot Air Screw was all banged up - irreparably mangled. Later I ran into some other carb problems and bought a new used bank of carbs. But these ones look just slightly different! Can anyone explain to me what the red circled doohickey on the #2 whether or not I can use these carbs? When I clean and rebuild them do I need to do I need anything special?

Thanks,

-Jeff

[Nessism]

VM24 carbs w/accelerator pump from a KZ650. That version has the dreaded vacuum sense diaphragm that the guys on KZ Rider say makes them temperamental.

[zed1015]

Hi, Jeff..
As Nessism has pointed out they are VM24mm pumpers with the sense diaphragm (the one with the triangular cap) and along with the VM26 versions are the worst of the bunch.
They are also too small for your 750 and will strangle performance.
Any of the VM's with horizontal ribs on the slide body are 22 or 24mm and should be avoided for your aplication.
The VM 26's (or even VM28's) you need are distiguished by the lack of ribs in that area.

[Jeff Abgrund]

Hi, Jeff..
As Nessism has pointed out they are VM24mm pumpers with the sense diaphragm (the one with the triangular cap) and along with the VM26 versions are the worst of the bunch.
They are also too small for your 750 and will strangle performance.
Any of the VM's with horizontal ribs on the slide body are 22 or 24mm and should be avoided for your aplication.
The VM 26's (or even VM28's) you need are distiguished by the lack of ribs in that area.

OK, thank you. They were sold to me as being from a GS750, but clearly I didn't pay enough attention. I will return to the hunt for the proper carbs.

-Jeff