1976 kz750 twin B1 - starting issue Video attached

Cant get my KZ750 twin 1976 project bike to start. The starter clutch was shot so I rebuilt it. I also cleaned the carbs, I am getting fuel 125 compression in each cylinder (cold), and I am getting a nice blue spark on both sides. I am guessing its a ignition timing issue. But it almost seems as if the crankshaft is sticking. If I try to kick start it the kick starter sometimes kicks back at me (almost broke my ankle lol) So I am kinda afraid to kick it right now. Linked to a youtube video of what its doing. Any suggestions are appreciated. Thanks!

If the ignition timing is off it can cause the kickback you described. When the timing was off on my old BSA it would throw me into the air like a rag doll and I would end up on the ground with my shoe off rubbing my foot. :laugh: :laugh: :laugh: Ed

OK Ill start with trying to get the ignition timing correct. Is it possible to do this with out an Ohm meter? I set the point gap to spec. And I have a timing light but the timing light is only good if you can get the bike started.

If you set the points when they are just opening at F, it should be able to start. You can also use a light tester or make one, the light should go out when the points close, on when they open.
Steve

Watched your vid. Are the points sparking? If so, the condensers are bad.
Steve

Before attempting to replace or adjust the points the following is important to understand; timing is comprised of two separate components, and BOTH of these components MUST be set properly if the engine is to run well:

--- The GAP – this is the distance the points spread apart when fully open. This is set by adjusting the points. The GAP is the element that determines the DWELL. In essence, the DWELL is the number of degrees of points cam rotation that the points are closed and this controls the amount of time the coils receive a charge before firing the spark plugs.

--- The TIMING of the initial opening of the points (the point at which the continuity across the points breaks) controls the precise instant that the coils receive the signal to fire the spark plugs. This is set by turning the backplate AFTER the gap is set.

The manual will show how to set both the gap and the timing. If you don't already have one I HIGHLY recommend you get a Kawasaki Service Manual for your bike. They normally are available on eBay. Be sure to get one for your exact year and model bike. Ed

Points are sparking... they arent supposed to? This is my first non honda vintage project. Every honda I have done the points sparked.

I have set the point gap properly. I didnt realize the plate controlled when the gap opens that helps lol! If I understand correctly the gap should be open as the F passes the timing mark?

Thanks!

bowser881 wrote: Points are sparking... they arent supposed to? This is my first non honda vintage project. Every honda I have done the points sparked.

I have set the point gap properly. I didnt realize the plate controlled when the gap opens that helps lol! If I understand correctly the gap should be open as the F passes the timing mark?

Thanks!

If the condensers are shot, they will spark. If the points are dirty, they will spark. They should just open as the F passes. Bikes can run with sparking points but not well.
What was said above is right. Do you have a manual?
Steve

Did you take the timing advancer out? If so, it can go in 180 out. You have a 50-50 chance that it goes in correctly and it goes in backwards about 99% of the time....

Check the advancer assembly. If it is stuck in the advance position, it will never start.

I have a Dyna S but I carry my old points plate and cam just in case. Had one leave me stranded years ago.
Do they make them for the twins?
Steve

The previous owner had the advancer out he replaced the points. Its very possible that its 180 out. I will check it out. Is there a way to tell if its 180 out or when I put the advancer back in how will I know its correct?