'81 KZ550 Ignition advancer stuck

Hi there everyone. My advancer mechanism is stuck. Would soaking it in PB Blaster for a while possibly help unstick it, or should I grab the one kz550 advancer available on ebay while I have the chance?

The Kawasaki.com site shows that an '80 thru '83 kz550 advancer will fit, but does anyone know if those from other KZxxx(x)'s would work? I'm assuming not because I'd think others would probably have bigger or smaller weights depending on engine size, but I don't know much about it. Would it be possible to put the weights from my unit on one of another size engine (if I could get them off)?

Does a stuck advancer effect performance at all engine speeds, or only over a certain rpm? What would be the symptoms?

This bike has electronic ignition btw.

Any advice greatly appreciated!
Thanks.

Depends on which way it's stuck. If it's stuck at the F mark, it will start and idle fine, but won't rev up past a certain RPM. (That is usually where it gets stuck.)

If it somehow managed to stick at the advance position (I don't see how it could), then it would be almost impossible to start and would kick backward when you try.

Other advancers may physically fit (From KZ650 or KZ750-4), but will have different advance curves, so you won't want them unless you can modify them (not easy at all).

My signature has a lot of links for KZ550's. On my 550 website there is a link to checking the advance mechanism (with help from Patton). Scroll down here

Don't soak it in solvent. It may melt or dislodge the ruber advance stops. They are really tiny and easy to miss. You should try to disassemble it and clean the individual pieces. If it's too far gone for that, then try to get a new one, but save the old one. Someone else may be able to save it. They are not always easy to come by.

Wow, that was fast! Thanks so much. I think I've hit your 550 website about a hundred times since I've started this motorcycle venture(obsession)
It start's pretty good and F mark shows up with a timing light, so I guess that's wehre it's stuck. The ends of the weights are pretty tight against the shaft. Would they be further away from the shaft if they were stuck in the advance position?

I can get the c clips and top washer off, but the weights don't seem to want to come out of the slots on the shaft.

Yes. They move away from the shaft when advanced.

After you remove the advancer (the small bolt at the tip, not the bigger hex),
if you can put a drop or two of penetrating oil, you might be able to wiggle the advancer rotor off the shaft. You have to get it to move before it can come off, though, since it has to be advanced before it can lift off.

OK, thanks, I'll give it a try. I think I already messed up the rubber stops, one of 'em anyway... it's loose. Could it be superglued or something?

Possibly. Whenever I've found the rubber stops missing, they were usually gone.

When the rubber stops are missing, the advance range increases. So it is important to make sure the advance at high RPMs is correct to prevent damage to the motor. With the stops missing, the advance will be slightly retarded at idle, but that is much safer than having it too advanced at high RPMs.

Both stops are still present, but one wiggles a little when I take the c clip off and gently pry up on the weight. It seems to be held tight against the shaft when the c clip is installed. I'll try to re-adhere it if I can ever get it disassembled.

This is a little difficult without pictures, but what you have to do is rotate the advancer rotor on the advancer shaft to the correct position, then the rotor advancer will lift off of the shaft. Then the two arms can come off.

The arms and springs and c clips should all be in place when you lift off the rotor. then you take them apart. It's easier that way since the springs can retract more.

Assembly is opposite of removal, but is trickier because you have to hold both arms at the exact right position. an extra hand or two would help.

OK, thanks. I'll just have to keep at it to see if I can get the thing to turn first... it's stuck solid.

Got it unstuck yesterday. Wasn't a big deal, just sprayed a little pb blaster around the top and let it soak in for a while, wrapped the rotor with some rubber and lightly secured it in the vise to keep it from turning, then stuck the bolt with hex nut through the top and applied light pressure to the the hex nut with a wrench until it loosened. Came apart pretty easy after that. Did have to superglue one of the rubber stops back on, but it seems to have done the trick. Cleaned up the rough spots a little with some 600 grit, greased it, put it back together & reinstalled... works like a champ! Thanks for your help Loud! This thing pulls like crazy now!!

Excellent! Nice job.