Cheers Chicken. I’ll have more of a scrounge around next week. I will just wash it with the hose like I do the rest of the bike. I won’t be putting it in the washing machine every week 
I want to do it to stop burning holes in my riding pants that eventually rip into an even bigger. That an dthe fact I’ll look fully sik.
Technically, it ruduces the radiant heat emitted from the pipe and keeps cylinder head temperatures (and thus pressure) lower. If people sell that to you for a bike it’s largely bullshit though. With the exposed nature of the engine to the elements I think it will do sweet FA. A car’s engine bay with a dirty big turbo is however and entirely different matter….