Mushy Front Break Lever - Harley Forum

sinolav · #1 08-14-2009, 01:11 PM

What can be done to correct the “mushy” break syndrome?

I changed out my brake pads on my 03 Ultra, got rid of the old fluid, replaced it with new fluid, (the correct type). I cleaned the pistons and piston boots. I have bled the brakes several times, several ways, even did a reverse bleed. I still have a mushy front break lever.

I have to squeeze it two times before I get a solid feel. It’s like when you press the pistons in to change the pads, then you have to squeeze the lever a couple times to get a good seat on the pads. Any ideas?

HarleyCruiser · #2 08-14-2009, 02:32 PM

Warped rotors will cause the pads to push the pistons back in the calipers and give that symptom. I would do a runout check on them.
How many miles on the rotors and have you also checked the thickness of the rotors? There is a minimum thickness stamped on the rotor.
As the rotors get thinner they have a tendency to warp.

aceharleywrench · #3 08-14-2009, 02:35 PM

Jack the front end up & put a dial indicator on the rotors to check for runout,you should have no more than .010".I will go so far as to guarantee this is your problem since you get a solid lever after a couple of pulls.The 2000 & up rotors are very prone to warping or bending (especially during tire changes)

Harley cruiser must have been quicker at typing than I am,he beat me to the punch!

BaggerDad · #4 08-14-2009, 03:33 PM

how did you bleed the lines? if there is any air in them you might have a problem.

unclepsycho · #5 08-14-2009, 10:37 PM

If the brakes were solid before you worked on it and now after a total re-build of the system and new fluid, there has to be air hiding in there somewhere.
Have you tried to pump the brake lever and hold it while you open the bleeder? but I'll bet you tried that..... I have had to do that 4 or 5 times once to get that 'hidden' air out.

Make sure the bleeders are facing up...near the top of the caliper??? do you have dual brakes, and accidentally got the calipers swapped side to side???

sinolav · #6 08-16-2009, 09:11 PM

Thanks for the replies. My next step will be to check my rotor run out and thickness. I have 25000 miles on the bike.

I didn't swap my calipers or rotors, just replaced the front pads.

As far as bleeding, I have bled the brakes nearly 10 times. I did pump the lever a number of times, then opened the bleeder a bit. Did that until the master cylinder was close to being empty, but still had enough fluid to cover the hole and bottom of the reservoir. This worked the best.

I even tried a reverse bleed with one of the brake bleeding hypodermic bodies. I am so glad my bike uses dot 5 fluid. Even with things covered, when that short line popped off the bleed valve, fluid still got to places I didn't cover!

Bigincher · #7 08-16-2009, 10:20 PM

You didn't happen to just install stainless braided lines, did you?

unclepsycho · #8 08-16-2009, 11:26 PM

Ok, I looked in my 06 Ultra book (I think it is very similar if not the same as yours)and it shows an 'anti-rattle' clip. If it is hung up, I suppose it could be the culprit....if you have those on your '03?

Here's another idea, those ears on the pads... gotta be positioned just right... my book shows an odd arrangement... do you have the manual to show you this?? if not I can copy the page outta my book and see if it looks like your bike.

frisco-rigid · #9 08-17-2009, 02:42 PM

Sin

I can only give you my experience..

I have warped a couple rotors over time and did not get any mushyness..
All I got was dragging..

I have run my rotors waaay below "Min" thickness and did not get mushness..
Actually,, nothing happened,, just kept on braking as usual..

I appreciate that you've bled & bled & bled.. Like Unc said,, be sure all little doo-dads are correctly installed..

I've also done the reverse bleeding,, works fine, but I personally like the old kinda bleeding..
You said you pumped the lever then opened the bleeder a little bit..

Maybe this is how you do it, but if not, ya might try it..

Slip your Box-end wrench over the bleeder valve..
Then slip a long enough tube over the bleeder to loop down to drain into a container.. Use a clear tube to see the bubbles, you know, just for the fun of it..
Fill the M/C..
With bleeder open, pump the fluid thru till it starts to exit the bleeder and flow into the container..
Close the bleeder and pump till you get resistance,, then slowly open the bleeder as you finish that pump stroke almost to the bottom of that stroke and close the valve quickly..
Repeat same.. Repeat same..
The M/C may begin to empty, fill it,, repeat till it does not feel mushy anymore..

In my experience, trapped air as Unc sugg'd has always been the reason for mushy,, might be other reasons but I've never seen em..

Have a ball

Bigincher · #10 08-17-2009, 02:54 PM

Frisco, have you ever heard that stainless braided brake lines can cause mushiness? I've heard that a lot, but no first-hand experience.