My first HD was a 2007 FXSTC that I got in Aug 06. I bought a service manual for it and every HD since then. All of them were DOT 4 for the brake fluid.

One of my winter projects was to bleed the brakes on the bikes. The last one was the 2000 Deuce that I bought about 3 years ago. When I finished the work and was installing the rear master cylinder cover which was chrome so the previous owner had replaced it as stock was black I saw that it said use DOT 5 on it.

Don't know anything about the various ratings for brake fluid. I just use what the book said. All my manuals say DOT 4 but I don't have a manual for the 2000.

Does anyone recall if HD used to use DOT 5 then and is DOT 4 okay?

 

The service manual for the '00 Deuce says DOT5.

 

Thanks. I'll just get some DOT five and completely flush out the system. It is an easy task anyway especially with the vacuum pump.