The track has been installed for well over a year now and it's never had a thorough clean. In recent months, I have been following a long thread on SlotCarIllustrated about an Australian lubricant called Inox. Racers have been claiming amazing things about this stuff - so much that Inox themselves now have picked up on the slot car market on their own website - and I thought it was about time I gave it a try. It's not available in the UK but didn't cost much to get it shipped from Australia.
I made a cleaning tool by glueing a couple of old Scalextric guides (without the metal brades) into a piece of wood, so that I could easily guide a cloth sprayed in Inox along the track rails.
You can see from the photo how much oxidation came off the track. The rails didn't look too dirty (the loft isn't damp so no serious corrosion) but the cloth was black by the time I'd finished both tracks.
In cleaning and protecting the tracks, the Inox has significantly improved the connection between the car braids and the rails. This leads to noticeably faster driving and quicker lap times. I estimate this has taken a second off the quickest cars' laps, and more off the slower cars. Certainly I found I had to be more careful with the trigger than I have in recent months. A great improvement.