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Well last night I pulled my GS carbs off of the rack that holds the 4 carbs together, then did the same to my eBay KZ650 carbs… swapping out the racks. So in the end, I now have the KZ rack on my GS carbs. These two sets of carbs do use the same rack, so it was a direct swap. What this did for me was that my busted Idle Adjuster is all attached to the rack… so now the working Idle Adjuster from the KZ carbs is on my GS carbs & I finally have a working Idle Adjuster on my GS carbs.

After I completed the transplant, I went through & swapped out a few fasteners from the GS carbs that were in rough shape, and exchanged them from the non-rusty set of fasteners from the KZ carbs.

I do like the Kawasaki KZ Idle Adjuster better because the Suzuki GS adjuster has a plastic knob on the end, while the KZ’s is all 1-piece metal. This seems like it will be much more durable to me.

This was all pretty straight forward stuff, kind of like a building model as a kid… just disassemble what is needed & reinstall the other equal items. Here is a great set of pdf instructions that I had at my side during this process http://thegsresources.com/files/vm_carb_rebuild.pdf

First I removed the 8 countersunk fasteners on the back of the rack, this is partially what holds the carbs to the rack. Next, I needed to remove the shaft that all 4 carbs hold onto at the top of them. This shaft also is what the throttle linkage grabs a hold of to pull the slides up when you turn the throttle.

After I removed the shaft from all 4 carbs, now the rack is free to be pulled off of the 4 carbs. In this scenario, I was careful not to separate the four carbs from each other, with the rack removed, I believe all that is lightly holding them together is the plastic & rubber fuel lines that go in-between each of them. No harm if they did separate, I just avoided taking the step to put them back together.

Next, I cleaned up my donor rack from the KZ carbs & simple placed it onto my GS carbs, since the rack is the identical Mikuni part #, it just bolted right on. Doing this gives me my working Idle Adjuster since this came along with the transplant as already attached to the KZ rack.

Then I just reversed my steps from un-assemble of the parts. Once the GS carbs were put back together, I did a mechanical sync of the slides… making sure that they both closed & opened the same amount. This is done with the adjuster on the top of each slide. Once that was done, then I installed the 4 carb tops, re-assembled my old rack onto the KZ carbs & now I have my working GS carbs finally!!! I know that I have not explained every step to what I did, but it is all explained in better detail in the pdf link that I listed above.

There were 2 difference that I spotted between the parts that I exchanged. First was the Choke mechanism. On the ‘78 KZ, the arms that actually rotate up & down, that lift the choke plungers up & down… they had a little different shape to them. I do not know if this comes from a Mikuni change in ‘78 from ‘77, or if it is a Kawi Suz difference. Second was on the KZ, where both ends of the Throttle Return Spring attaches, the KZ has a rubber condom over the metal… so that both ends of the springs were attaching to rubber, instead of metal. I guess I’m going to presume that this is a nicer feature that Kawi added, over the basic metal set-up that the Suz has.

I know that there will still need some jetting changes most likely, plus vacuum syncing & possibly more adjustments. Tonight, I hope to install my updated GS carbs onto the GS. At this point, I still do not have my electrical problem resolved, so even if I do complete the carb install tonight, the bike will not even turn over until my Ignition Switch is fixed… which hopefully will only be another day or two.

This entry was posted on Wednesday, August 20th, 2008 at 9:19 am and is filed under The GS Project. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.