Some will slide on with a bit of persuasion. Others are very tight.
Be extremely careful if you attempt to tap them on as the key can hit the bronze bushing and raise a burr wrecking the whole works.
DAMHIK.... If the cases are still apart you can install the cams in the timing side and tap the gears on while supporting the other end of the shaft.
But-- The tool really does make the job go right and I highly recommend it.. If you are going to mess about with old brit bikes the tool may be a good investment- it also works on some Norton gears and I've used mine for all sorts of jobs on various bikes.
My two cents, Todd
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