Hello! I have a 1975 Z1-B 900. I rode it about two weeks ago. It ran fine. About a week later, I went to start it up, and it would only run on two cylinders, No. 1 and 4. I have replaced the spark plugs,...
Your motorcycle has two sets of points. Each point set operates one coil or two spark plugs. You can try cleaning the point contact surface with a point file.The point may be worn and grounding out to the frame. The bike may need two new sets of points properly installed and timed to run on all four cylinders again.
1st -- Adjust gaps -- Do this separately for each points set. Turn crankshaft clockwise using 17 mm wrench to widest points opening and adjust gap separately for each set of points at 0.3-0.4mm (.012-.016 inch). Each points set has two base screws to very slightly loosen thereby allowing movement to open or close gap, then retighten after setting gap. The widest gap happens when the heel is resting on the highest part of the cam. At this stage nothing but the gap has been adjusted. But this is important because proper gap does affect the subsequent timing procedure. And other screws have remained tight.
2nd -- Set Timing -- Each points set has two mounting screws and pry slots which can be used with strobe light (after slightly loosening the two mounting screws) to align the respective F marks with the timing mark. But if the adjusting plate doesn't travel far enough to allow correct adjustment, then loosen the three mounting plate screws and move the mounting plate.
3rd -- Tighten and recheck --Tighten all screws and recheck timing with strobe light.
Aug 16, 2011 |
kawasaki Z1B Motorcycles