2012 heritage with front brake problem
 

The front brake lever loses pressure after it sits a couple days. The dealership has attemped to fix twice and they think all is well as the brake lever is firm and works well for about two days. I then get on to ride and the lever goes to th grip with little brake. I can give them a couple pumps and they'll be good for the day. There's got to be air leakage somewhere but how do I find it? The cycle just had the 1000 mile service done and this was the dealership 2nd attemp to fix. Dealership is 150 miles away so if I can fix it myself i'd rather unless it will take a new master cylinder or the like. Any input will be appreciated.

Check all possible places for air. All the banjo fittings, the master cylinder cover, and the caliper. If there was a leak you would start to see some fluid somewhere unless it was the master cylinder cover or the master cylinder is bad. But it definitely is not normal, be careful riding with that.

sorry to hear bout ur prob. i actually just bought a 12 lo. i test drove 1 at a dealer i didnt buy from and the 1st stop on my test ride was a scary 1 cause i had very little front brake. not sure if the bikes share the same front brakes. the next 1 i tested was fine and i bought it. idk good luck man

My 2012 Deluxe leaks brake fluid form the reservoir. Brakes work fine but it's annoying to have to clean brake fluid every other ride.

heritage front brake
 

Just to let you know I've looked closely several times and there is no indication of any fluid leakage at all in any places the brake line goes. Is there any way to actually test the master cylinder and can there be air leakage without fluid leaks?

Demand the issue is corrected at your dealer. If necessary, contact HD corporate office.

Sounds like a bad master cylinder to me.

Air in the lines don't pump up. To make them harder you have to bleed them.

But if there is a leak in the master cylinder seal, then you can lose pressure that can be temporarily pumped back up. At least, that's been my experience in cars, never had a failed master cylinder in a bike.

Do you have ABS? I don't know enough about ABS whether this could cause a similar problem.

heritage front brake
 

no they are not abs.

if you squeeze very slowly does it go down or when it happens and pull it hard does it feel good? sounds like a master cyl problem. One other thing to look at is the rotor running straight? the brake pads could be pushing back, air is more than a couple pumps to get brakes. If there was a little air in the line it would bleed out of the system through the master res. they should be able to fix it leave it there for a few days as it looses the break after 2 days you said

It sounds like one of two things:

1.) The Master Cylinder Primary Piston Cup may be missing it's expander. The expander keeps the Piston Seal against the walls of the Master Cylinder bore when there is no pressure in the system. However one quick pull of the Brake lever should fix things (at least temporarily). You might try this. After the bike sits long enough to create the problem, see if grabbing the brake lever really fast gets the Brakes to apply with a firm Lever even though the amount of travel may be more than normal. If a quick pull on the Brake Lever fixes things temporarily then putting in a Master Cylinder Overhaul Kit should do the trick, or you could replace the entire Master Cylinder

2.) The front wheel and/or the Brake disk is slightly loose. After sitting for a time, the Caliper Piston is pushed back ever so slightly in it's bore. This pushes brake fluid back into the reservoir. A few pumps from the brake lever would restore the situation.