I try to stay right out of oil threads, I been riding my Norton as well other older British bikes for near 50 years, I live in a hot dry country and I do things differently to most but I have got long mileage out of my Norton and my old Triumph's air cooled motors, and the most important thing for me is I always run a Lochead oil cooler all year round even in winter and without a termostat, I also run STP mixture with my oil, but it works for me, my Norton has well over 160k miles on it and is only on it first rebore, I am still running my original valves in my head, my 850 motor was fully rebuilt with the stock cam built up to Combat specs, the head was shaved and lots of port work and my crank was balanced, I still run flat top pistons 40 tho oversize but the rebore and hone was done at tight tolerances and ran in at winter on a very cold night, infact I froze my balls off, my motor was built for the Featherbed frame way back in 1980 and was rebuilt 14 years ago when I had to replace the crank cases from hair line cracks around the main oil seal area.
The last rebuild everything was removed and installed in the new crank cases with new bearings, my oversize bores just got a light hone and new rings installed and the head only had new guides and a light head shave, so really not to bad for what oil I been running so I will say what I been running most of my Norton life.
When I first bought my Norton new back in 76 was last old stock 74 Commando model and the dealers used GTX motor oil and for the first year or two the motor ran very hot and that's when I installed the oil cooler and started to run 50 straight racing Penzoil ( we had a old American who imported it by the barrels from the USA here in Brisbane) as well the STP treatment, the Norton loved it and ran so well with it, but the last 20 years my oil man retired or died and then the Penzoil was produced here and was never the same as when I was using the old Penzoil, so now I run Penright oil for old classic bikes still with the STP added.
As I say I do things differently to others, run a oil cooler all year round without a throstat, STP mixed in my oil and for 46 years of riding my old Norton its still going as good as it always has, it was a everyday rider for most of it life but the last 8 years it has been semi retired since I bought my first Triumph Thruxton in 2013 and now my 2016 Thruxton 1200, I still take the Norton out regularly and with the Joe Hunt maggie it always start on the first kick every time and for 46 years of owning and riding it, it has been very reliable and good to me and have clocked up a lot of miles and long distant rides with only a few minor breaks, 2 failed EIs and 2 failed chain breaks and a dropped coil so not bad for 46 years of riding, the motor has never let me down and to me that's what oil and STP been running in my motor for all its life.
My Norton is starting to show its age but the motor is still very strong and is still built the way I built it for the Featherbed frame way back in the early 80s, its my HOTROD Norton.
Ashley
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