HOME and how to join Forum Open Area General Scott topics petroil mix Re: Alfred used petroil! Roger Moss

Roger Moss

Hi All. Just for interest, if you look at John Underhill’s 1913 TT bike with the rotary valve, there is no provision for lubricating the valve. It follows that he must have used petroil. With a racer, you need lubrication to be in relation to the load and speed and petroil delivers this. I use a modern oil at about 50:1 but with drippers to lubricate the synthetic seals I use. I notice one thing though, unlike historic castor based oils that tended to remain on the surfaces, the thinner modern oils tend to drain down into the bottom of the crankcase quite quickly. When you go to start again, the oil rich liquid has a tendency to drown the plug. If you try just draining the wells before you start, I think you will find it starts very much more easily. With petroil, it gets oil as soon as it gets fuel, so it will not suffer. Kind Regards Roger