It's teasingly close, but they won't just drop in.
The lobe and journal spacing are the same. The journal diameters are the same.
The old motors use a roller bearing on the sprocket end, the new motors have a plain bearing.
The end where the sprocket presses on is also a different diameter.
With a lathe and some time on your hands, you could make it work. If you had to pay for the machine work, Megacycle cams might be cheaper.
The poor boy stage 1 1/2 for the carbed 750s was a megacycle 318x2 grind on the exhaust cam. This reground exhaust cam was used on the intake side, and the stock intake was used on the exhaust. The cam timing went from;
Stock
Intake .335" @ 243 degrees
Exhaust .303" @ 230 degrees
to
Intake .355" @ 246 degrees
Exhaust .335 @ 243 degrees
This is about all the cam you can run with the stock valve springs. It worked better if the compression was bumped.
This trick didn't work with the fuelie bikes because the intake cam had the cam position sensor on it. It also didn't work with California bikes because the intake cam was pretty sad. You had to know what you were doing to switch cams like this without bending valves.
The 1K cams are used in newer 750s for a cheap boost. If the 750 intake is used on the exhaust, the timing numbers are pretty close to the modified setup above. It's a bigger boost in the newer bikes because the newer stock exhaust cam has less duration.
