Pedal won't move - Harley Forum

Hammerhead Pat · #1 05-28-2009, 06:35 PM

After going thru 3 brake sensors in about 4 months, I pulled the one off the bike and pumped the line as dry as possible to purge any junk that might be in there. Added good old dot5 and tried,tried,tried to get the brake to pump back up but it wouldn't build any pressure. Took it to an indy shop real close to home and he tried eveything, disconnected lines from caliper,line to master cylinder and he discovered the master cylinder was shot. Ordered and installed a new H-D master cylinder and bled, test rode and called and said come get it. So I go and pick it up, brake feels good and solid as I'm leaving and as I get to the light less than a block away, the pedal doesn't want to move at all. So I take it easy a little farther down the road putting a little pressure on the pedal to see if I could get it to move and it eventually did before getting tight and not wanting to move again. I turned around and went back to shop and showed him what was going on, and he played with the pedal and it acted the same way as it did to me. He took the bike back in and pumped 2 small continers of fluid thru the lines, I'm guessing there is no junk in the line, and it is still acting the same way. We agreed that I'd bring the bike home and get some mileage on it over the weekend and see if there was any change in situation. The bike is a 05 Sportster with forward controls and it has the long bar that connects the pedal to the pivot thingy that pumps the master cylinder. I couldn't find any type of binding in that area. The mechanic is going to call H-D and see if they have had any problems with the m/c. Any ideas out there? I think we're both stumped on this one

Thanks in advance.

frisco-rigid · #2 05-28-2009, 08:00 PM

Hi Hammer

Question---- did he replace the WHOLE M/C or just rebuild yours..
A rebuild kit is typically a couple O-rings maybe even new piston and boot,, things of that nature..
If the Whole M/C was replaced and it is the wrong size, like too big, it will feel like an anchor,, it won't seem to move and there will be very little braking at all..
For example,, If he removed a 5/8" and installed a 3/4" that could be it..
Do you have the old one.? Compare them Daddio..

I'll continue----

It sure sounds like something binding to me but you are sure there is NO binding with any of the moving parts like the rod and pedal pivot etc. etc.,, Ok then, with the info you've given this is what I would do first..
Slip a tube over the caliper bleed valve to direct the fluid away and into a container,,,, just like when you bleed the brakes,,, then open that valve..
Now push on the pedal to see if it moves,, you'll get air in the lines but no big deal cuz you'll just bleed it all again when you finish..

If it pushes the fluid out easily then it is NOT "junk" in the lines or the MC (unless it's the wrong one) but perhaps the Caliper pistons binding somehow..

If it still doesn't move then my guess would then be the piston in the MC since there is NO other binding that you found..

Remember the MC is just and simply a piston in a cylinder,, nothing technical at all..
Disconnect whatever you need to for access to the MC piston..
Now pull off/out whatever Keeper holds the actual piston in the master cylinder and remove the piston..
Make sure there's Not a piece of broken O-ring or such (yeah ok, that's junk) in the Cylinder..
Slide the piston in & out and look for Smoothness..
If the piston slides freely go to the caliper..

You will find the prob cuz the M/C's & calipers are sooooo freakin simple..

aceharleywrench · #3 05-29-2009, 08:00 AM

Not much to add,just make sure you have the correct amount of freeplay (outlined in the service manual) at the pedal.Insufficient freeplay will cause the brake to drag creating all kinds of unwanted effects,including the condition you are describing.BTW,I would never let a customer take a bike to "put some miles on it" with suspect brakes!

evoKENevo · #4 05-29-2009, 10:00 AM

Can't add much here...never had a hydraulic brake pedal bind up to where it would'nt move at all. But, just thinking (ouch) again... if your brake pads are worn down the puck will be extended that much further out of the caliper and more likely to get cocked/wedged in the caliper...especially if exposed to moisture/corrosion or just dried sticky fluid on it. More than once just a good whack on the caliper with a rubber mallet (driving the puck back in) has freed things up and new pads solved the problem...along with fresh fluid that's already been done here W/O leaks.

Meanwhile...like Ace said...would'nt ever tell someone to just go ahead and put a few miles on it and see

what happens !!

Hammerhead Pat · #5 05-29-2009, 03:11 PM

Guys, thanks for the quick replies!
First of all, I'll take the blame for bringing the bike home. I had just spent seven hrs with family and in laws at my oldest daughters graduation and I really wasn't up for standing in a 80* parking lot in dress slacks and shirt. I "needed beers" and a sofa

Frisco, it is new m/c, not rebuilt. I disconnected the linkage from the footpedal to the throw arm and everything moved smoothly, no binding.

Ace, the brakes are not dragging. They aren't even braking

Evo, my pads have only about 2k miles on them so I'm confident it's not them.

I'm getting ready to take the bike back to them, they called H-D and were told to return the m/c for another one. I'll discuss what info you've given me . They've been paid, so I'm counting on them to remedy the situation, I'm sure they will. On a more positve note, at least my rear brake light works when the pedal is applied

Thanks again and I'll keep you posted.

Gas Man · #6 06-14-2009, 04:31 PM

Did they mix DOT fluids? Did they use a non-compatiable DOT fluid for the o-rings in the system?

As asked... are you getting fluid from the bleeder? That would verify the MC is working. Then you should consider pulling the caliper and seeing if it will move. It could be froze.

Did they soak the MC components in the brake fluid the system was going to use?

Here's a pic of a basic motorcycle master cylinder. That is all that is to it...

You have this or similar

Then once you pull the boot and the little rod

Then you pull the jesus christ clip and this is the guts

Hammerhead Pat · #7 06-14-2009, 05:24 PM

It was a bad M/C. They put a new one on and everything is back to normal. Did a 75 mile ride this morning and all is well!

Gas Man · #8 06-14-2009, 06:20 PM

And that MC was brand new right? Bad out of the box? Crazy!

Glad to hear your back on 2

Hammerhead Pat · #9 06-15-2009, 04:29 PM

Yep, bad outta the box. The shop was an indy and the local stealership wouldn't sell him one so he has to get his parts outta St Augustine. So add about 4 days worth of mail time and I was without a bike for a week and a half( shop closed on weekends). But I tell you something, when I first went in there and told him of the problem, he said he could have it fixed in an hour or so. He only charged me for one hour labor and the $85 for the m/c. I know for a fact he spent at least 4 hrs troubleshooting and messing with the first one. While I was waiting for the bike I was getting pretty impatient but I really have to give the guy credit for what he did. I'll use him again if I need to.

Gas Man · #10 06-16-2009, 12:48 AM

Sounds like a stand up guy.

It also sounds like you have my murphy's law luck.