76 kz900 timing advance?

Hi guys, I'm trying to help out a buddy of mine with his
76 kz900 ltd. I've been doing a bunch of digging using the search feature.
I cleaned and rebuilt the carbs. Nothing is clogged.
Boots don't have a vac leak. I synced the carbs and adjusted the pilot mix screws. The bike runs great above 2000 rpm but will not idle below 2000. It dies. I came across a thread somewhere on here that discussed how the problem could be the timing advance unit thingy and valve clearances.. As far as the timing advance unit goes... What do I look for to see if it's bad? It should spring back correct? How does it work? I'm assuming that at higher rpm the (tings) should move away and retract when moving slower. Is this correct?


Oh... :blush: Where is the timing advance unit on this bike? Does anyone have a pic?
He does not have a service manual.

Thanks

76 KZ900 doesn't have pilot mixture screws. There should be air screws. Next, the timing advance is under the points cover... small round cover on right/front. Use an inductive timing light to set timing. Put the pickup on #4 plug wire and the mark on the case should align with the "F" mark for 1/4 at idle. When you rev the throttle, the advance will rotate clockwise when viewed with the gun to reach full advance at about 3500 rpm, if memory serves. To adjust 1/4 timing, loosen 3 phillips screws on back of plate and rotate as needed (timing should be set at idle). Then move inductive pickup to #3 plug wire and recheck for 2/3. You need to loosen points on right (they are 2/3 points) and pivot the points themselves to adjust timing for 2/3. Last, there is a valve adjust article on our website under "wg's Tech Stuff Index" that explains how to check the valve clearances and adjust, if needed.

Thanks WG.
The only problem I see with setting the timing as you say is that the bike will not idle under 2000. How do I check to see if the timing advance unit is working properly?
I will check out the "wg's Tech Stuff Index"

Post edited by: cnyl, at: 2007/04/05 22:52

Maybe i'm missing something.... Under the points base plate isn't that where the advance unit is? Sucks not having a manual!

WG, Awesome instuctions on valve adjustments! Is that Kawasaki tool still available? Do I get it from kawi?

Post edited by: cnyl, at: 2007/04/05 22:57

yes your advancer is under points cover.hook up your timing light and check your timing with it idling at around 1000 rpms i think it should be around 10 degrees watch the timing mark as you rev it up to about 2000 rpms should move up around the 25 degree mark.have you checked the points? you can make the little ramp shaped tool for holding the bucket down out of a scrap piece of metal;)

The genuine Kawi tool is sooooo much better than the Motion Pro tool it isn't even a contest. I have both.

To check advance, like I mentioned, make sure timing at idle is OK... line on case lines up with F mark, then REV THROTTLE and see the advance pivot around clockwise... if it does and then comes back cleanly when you let off the throttle, it is fine. The advance should be carefully removed and the doo-hicky in the center removed and you should clean/lube (using grease) the center of the advance so the thing can pivot on the crank easily. This is part of maintenance.

OH YEAH... I got to thinking about this issue... you mucked with this fellas carbs. Did you dissamble the slides from the slide actuator rod? (the long rod the slides bolt to)??? If so, you likely didn't bench sync properly. See the bench sync instructions I gave the "longhair" fella in the carb section just yesterday. You won't get the bike to idle in the correct range unless you bench sync as I describe.

Thanks guys.
I have not cecked the points yet. Speaking of points, My buddy also wants me to install a dyna electronic ignition for him... Ummmm ok, how do I do that??
WG,I did not take apart the slides from the slide actuator rods but it looks like the bendable tabs were messed with. When the bike was brought to me 2 of the carbs were non responsive. My buddy had a "friend" of his work on this bike, so who knows what was done. I found alot of problems so far.
WG... I will do a bench sync as you suggested.

Thanks again

The Dyna S install is pretty painless most of the time. You swap the points plate for their ignition plate and swap the doo-hickey in the center. This thing is a bit with a magnet pressed in that passes the pickups as the crank rotates. One little secret of installing this thing is to read the instructions. Since this doo-hickey can go on with the magnet pointing one way or the other, if you put it on wrong, you will end up getting confused with the wiring to the coils... they have a good set of instructions. Once you have their Dyna bolted in, you just connect the coil hot wire to the power leads from the Dyna S. They give you a nasty little blue crimp blade connector that you should throw away. Solder the power wires! Their leads from the dyna S don't match the colors on a Kaw. They use black and white wires but DO have little pieces of tape where you connect to the coils to help you figure out which goes to which... important thing to remember is LEFT pickup is 1/4 (same as points) and RIGHT pickup is 2/3 (same as points). Once you have the thing on and wired, fire the bike up and timing is the same as with points. Loosen the three mount screws and time 1/4 by rotating the plate (using inductive timing light with pickup on #4 plug wire). Then lock the plate and move the actual 2/3 pickup to time it. It is held on with small socket head bolts and they provide the little allen wrench. Again, just follow their instructions. Make sure to have the timing light on hand. I don't care for their static timing as it isn't all that accurate.

Thanks WG... I'll let you know how all this turns out.

I bench sync'd the carbs after cleaning every hole and checked the float height again. This baby still will not idle under 2000. There are no vac leaks.
What should I do next?

Thanks.

Post edited by: cnyl, at: 2007/04/08 12:43

have you backed out the idle screw, also if the cables are adj, wrong they can be holding it open a bit causing it to idle high

If I back the idle screw out so it will drop down under 2000, I have to use the throttle to keep it running. The throttle has plenty of slack.

Thanks.

Post edited by: cnyl, at: 2007/04/08 14:22