Jet Needle adjustment 78 GS 750

[Guest]

I've looked every where, sorry if i missed it. Whats the best way to get to the jet needle clip for adjusting the midrange on my 78 GS 750?
Pic's would be helpful if anyones got them.

[TwoWheelKid]

In the same boat as you...

I've looked every where, sorry if i missed it. Whats the best way to get to the jet needle clip for adjusting the midrange on my 78 GS 750?
Pic's would be helpful if anyones got them.

[OldVet66]

Here is a link to BikeCliff's Website. Scroll down for a rebuild tutorial for the VM Carburetors. It shows them disassembled so you will see what you have to do. You have to go in through the top. I don't remember if the needle can be removed without removing the bell crank shaft. If you do, a bench sync and syncing them on the bike will be necessary. Probably not a bad idea to do that anyway: http://members.dslextreme.com/users/bikecliff/

[8ball]

You have to remove the carbs and remove the shaft that lifts the slides. There is a bolt on each linkage, one on the throttle cable cam and a screw holding a thrust plate. Once you slide the shaft to the side, you can remove the slide. There are two small screws that hold the lifting arm to the slide.

[Steve]

I have heard it said that on some bikes, you don't need to remove the carbs, you can just pull the throttle shaft, then the slides.

Have not had the opportunity to try it myself, so can't say for sure.

.

[G-3]

Thanks guys, but i muddled my way though it last week! went well!

[8ball]

This is a set of old corroded KZ VM carbs I have, but they should be pretty similar:

Once you have the carbs off and the caps removed, you have four of these bolts:


There is one bolt on the cable pulley (cam). It is under the idle screw, so you might have to remove that, and I would suggest taking the spring off the cable pulley:


Then there is the thrust plate and screw:



Now the shaft should be able to be slid side to side. I don't take it all the way out. I just slide it to the left enough to remove the right to needle slides, then once I adjust those, I put them back in and slide the shaft to the right and do the left two slides.

As for the slides themselves, There are two Philips screws down in the top (They are actually JIS, and I recommend getting a set of JIS screwdrivers):


Here is the slide and needle exploded view:


And the needle, spring, spacers and clip in the order they go:


If you look down in the top of the slide before you take it apart, you will see that the two screws are located at 12 and 6 o'clock. There is a vent hole at 3 o'clock. To reassemble the slide, I use a straight pick to line up the vent hole in the lift, the plate and the slide.

[G-3]

It would be nice to sticky those pic's, all the post make it seam like a less complicated job!