My bad for not checking out if Harley DID run DOT 5. I made the mistake of assuming all Harleys used Dot 4 and only special cases used DOT 5.

But my point was that Dot 4 and DOt5 cannot be indiscriminantely mixed. or as stated, a system must be thoroughly flushed CLEAN before putting different fluids in.

Of course, if its a stock app, then no point in using anyhting other than whats called for, systems are designed with one fluid in mind. Good luck!

 

DOT4 and DOT5 do not play well together. Check with a real expert, but I thought I heard that if you want to swap from one to the other, just flushing or cleaning is not sufficient as you will never get all of either type fluid removed from the lines, seals, and caliper. It looks like you have 2006 which is definitely DOT4, just as your master cylinder cover states. If you completely filled the reservoir with DOT5 and bled it into the system, you may have contaminated the system and might need to overhaul the entire brake system. You could try to flush a lot of clean DOT4 through the system, ride it and do it again a few times, but you really want to be careful with something as important as your front brake.