I've owned my one since 1988, and just loved the sound and feel of it spinning over between 7-9000 rpm, occasionally kissing the red between bends! All i've done engine wise was to replace camchain and std piston rings @ 15,000 miles. Had to replace camshaft and some rockers, but that was down to my poor storage conditions whilst it was off the road. The mileage is now 33,000 miles, not high, but I cannot get out and about too often these days. Everything else inside the engine is original, and when I do go out on it, I still like to run it up to about 8,000rpm, it feels so GOOD! Regular oil and filter changes pay dividends.
Remember, they are only little pistons and rods, and can suffer more damage through "lugging" at low revs. Don't be a "con-rod bender", it ain't a diesel. Enjoy it as it was meant to be enjoyed. In their heyday, they were bought by young men who constantly wrung their necks, it's a tribute to their quality that there are so many still in existence. Don't lock it away completely over winter, if we get a nice cold dry morning with a clear blue sky, get kitted up and give it a blast, these old carburetted machines breath beautifully on such days.