TOPIC:

I can't get my bike to run right for anything. I've tried everything I can think of so far. It runs rough, runs very rich, puffs black smoke out of the exhaust and keeps fouling plugs. Rebuilt the carbs, checked timing, new coil, new wires, new plugs, doesn't seem to matter.

A few people have suggested that it sounds like the ignition timing is off. I've played with the timing a little bit but I honestly have no clue what I'm doing.

I have yet to have anyone tell me which direction on the stator advances & retards timing. Which one is clockwise, which one is counter clockwise?

Second, what in the blue hell do the marks on the advancer mean? There are two small marks about 1/16" apart, then a bit to the right of those is a mark labeled "F", and another mark labeled "T." I don't even know what they mean.

I don't know anything about points, and I'm feeling pretty lost (and pretty frustrated) with this thing, and I've missed out on some prime riding weather.

Can anybody help me out here or am I just gonna have to go to a mechanic?

F is for firing and the T is for timing. Not to familiar with how to set iming on the twin motors.

If you don't have a manual go here to this website, look at the second post, and download it. All the answers about timing are in the manual.
www.armbell.com/forum/viewtopic.php?t=3248&mforum=kz400

When you rebuilt the carbs how did you set the float level?

I have the same manual biquetoast posted there, on CD. It really doesn't tell you much about setting timing except with a dwell meter, which I don't have. I did the static timing method described in that manual, using an ohmmeter. To set it like they say, with the points opening just as "F" is passing the timing marker, I had to have the stator turned as far counterclockwise as it would go.

And, I didn't set the float level. I didn't know that was a requirement. I thought you just put new jets and needles and such in the carbs and you were good to go.

I really don't have any experience with carbs either.

ghunt81 wrote:

... To set it like they say, with the points opening just as "F" is passing the timing marker, I had to have the stator turned as far counterclockwise as it would go....

Perhaps the advancer unit is stuck in the fully advanced position. It is supposed to operate freely as the weights overcome the springs via centrifugal force with increasing engine rpm. Maybe a spring has weakened or broken, but the remedy might be to disassemble, clean, and lube the advancer unit. Be careful to reassemble it in the correct position and not 180 degrees off.

Good Luck!

Autozone, checkers, Pep boys... Dwell meters are under $40.

Seems like a worthy tool to have especially if this is what your service manual is providing you in timing your bike and in the regards to where you're frustrated and truly not knowing what your doing regarding the timing.

Look at the bonus side of purchasing this meter, you can also use this on your car tune ups...

OMR

dont know about the twins, but I prefer to set the timing with a light at the rpm spec in the book, by doing this you will also be able to see if the advance mech is working.
I volt ohm meter is needed to be able to check to make sure the charging system is working and also check voltage at the coils, both of which can cause a symptom you are seeing.

I know nada about using a dwell meter. I would set timing using an inductive timing light. To do this, you loosen the three M5 screws that hold the points backing plate. At idle, the idea is to have the line on your engine case align with the mark adjacent to the F mark on your mechanical timing advance. You turn the plate one way or the other to get them to line up while you hold the light on the mark area. Once they align, the bike's ignition is timed. You then just tighten the three M5 screws that hold the plate. The points should also have an adjustment at TDC where you align the pistons at TDC using the T mark on the mechanical advance and set the points gap with a feeler gauge.

Not sure what the points gap should be but I am sure it is in that online manual somewhere.

ghunt81; There are a couple of issues here. The Dwell meter is used to set point gap. It can be done without the meter using feeler gages. Seems like 0.016 inches if memory serves. You will find that sometimes there is not enough adjustment to get the ignition timing spot on, especially with worn heels on the point set/sets. You can remedy this by slightly altering the point gap (previously set with feeler gages or dwell meter). Make sure there are no "bumps" on the faces of the contacts. The bumps come from the condenser not doing it's job and allowing the current to arc from one side to the other, causing metal transfer. You can remove the bumps with a points file, although the material is harder than the hubs of Hell. Once you have the gap set, proceed with static timing, using the ohm meter you have. The points should just open and break the circuit as the "F" mark lines up. You can test the advance unit by simply twisting it with your fingers. Does it feel smooth and return to the original position? If not, dissassemble and lubricate. The "T" mark is used to set the piston at top dead center, ignore it for timing purposes. I hope this long winded story helps you, ride safe, Steve

I've had the stator off and I know neither spring on the advancer is broken, but it does kinda look like it could be sticking, I don't know. I couldn't get it off earlier so I haven't removed it to check it out.

Also, I haven't tried to set it while the bike was running (didn't know that was safe) but I have had a timing light hooked up, every time I shoot it the "F" mark is off to the right of the timing pointer.

Plus the bike will generally only run for maybe 30-40 seconds at a time, which makes it really hard to actually set the timing.

Points gap according to the manual I have is .3-.4mm. I have it set at .35.

I am at a loss here... the stator is on the other side of the bike from the mechanical advance mechanism isn't it? TURN THE POINTS PLATE TO LINE UP THE MARK ON THE ENGINE CASE WITH THE MARK ADJACENT TO THE F. Stop the bike when you have ignition timing adjusted, tighten the 3 M5 screws. Start the bike and put your timing light back on at the same place and watch the marks as you rev the engine to about 3000 rpm. You will see the mechanical advance ROTATE.

Sorry about the bad info on the points gap stuff... I haven't had a points outfitted bike for MANY years. I thought points gap was set at TDC but I guess it is at the F mark as well. Kind of makes sense.

The stator is OVER the advancer. They are both on the right side of the bike. The advancer has the lobe on it that opens the points, and it has the timing marks on it.

Oh yeah I forgot to mention the points and condenser are both new too.

Anyway I can't get it to even run good enough to really run it to 3000 RPM, because the longer I hold the throttle open, the worse it starts to sputter due to the rich condition.

I really think this is a carb problem and not timing related.

I've read about this clear plastic tube test, and I searched and saw what people were talking about, but how do I measure the level and what level do the floats in this thing need to be set at?