Kawasaki KZ650 cafe-racer. Shopping post. Part 5. Some performance parts.

I have had enough of contact ignition maintaining and adjusting in the beginning of my motorcycle life some 15-20 years ago. Thus, I had no slightest intention to leave original contact ignition system in Kawasaki KZ650 cafe-racer project, nor I was fond of its old wiring and electrical components.  The solution for replacement of KZ650 contact ignition is quite known: to use ignition picker, rotor and igniter unit from late air cooled inline four Kawasaki 750. My choice of model was obvious:  I just bought Zephyr 750 ignition picker, rotor and complete wiring with all units included. Wiring was declared to be removed from bike with only 15K km on it and looked like new.

My next goal was to give a bit more of life for engine on high RPMs.  In prime time of Kawasaki KZ650 there were quite a lot of performance camshaft for every taste, from so to say bolt-on camshafts with lift higher for some 0.6mm from standard and ending up with camshafts that required change of valve springs and other deeper modification of engine.  Now these camshafts are rare to find and very expensive to buy, but again, there is simpler solution for adepts of mild tuning. Yep, again parts form bigger brothers. KZ750 camshafts’ lobes are higher for around 0.5mm than KZ650 camshaft lobes and are bolt-on for KZ650. My choice was again for Zephyr 750 camshafts. Its exhaust camshaft has no gear for tachometer, but I don’t need it anyway as I am about to use tachometer without mechanical drive.  What is really important, it is possible to find a set of Zephyr 750 camshafts removed from engines with nearly zero millage as I done. Thus here are Zephyr 750 camshafts and that’s how they look comparing to KZ650 camshafts. As you may see, sprockets are interchangeable and there is no difference in lobs positioning.

According to measurements I made, height of Zephyr these very camshafts lobes are 36.28mm while KZ650 camshafts lobes are 35.78mm, so there is exactly 0.5mm of lift difference.  And, as you may see from photo below Zephyr camshaft lobe also is fuller than lobe of KZ650 camshaft. This will give some additional performance on high RPMs and these camshafts will perfectly complement  Wiseco 700ccm forged pistons kit I already have for KZ project.


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