Okay, not specifically bike related but figure it may still be relevant to some older model bikes. I'm planning on doing a major upgrade on my cars brakes very soon (better rotors, better pads, braided lines), and obviously as part of this will also be changing the fluid. The cap on the reservoir however states DOT 3 only, but I'm not sure if this is purely because of the age of my car (it's a 1989 build), or if there's a genuine risk of damaging something by using DOT 4 or Super DOT 4. I would like to move up to a higher temp fluid but everything I've looked at so far that states "for DOT 3 or DOT 4" always has in fine print on the back something along the lines of "not suitable for all DOT 3 systems. So just wondering why there would be a problem with using DOT 4? And does anyone know of any DOT 4 fluids that would be safe to use?