Front Master Cylinder and Caliper

Question I reduced the front brake lever play to 1″. I had to make a panic stop which heated the hydraulic fluid. Very soon after, the front wheel locked up. When cooled down, I rode away. I never heard of this on any vehicle. Please comment. P.S. Harley Softail


Roy Via Email


Answer We would not expect the brake fluid to drastically heat up from one quick “panic stop”. More typically, brake fluid will over heat from too much pad contact while in the neutral position. We don’t know what you did to reduce your lever play, but you need to verify that your front wheel spins freely. Also, verify that you do not have a warped rotor. If you continue to have problems, you may need to consider rebuilding your front master cylinder & caliper.



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Harley Master Cylinder Rebuild
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4 Responses to “Front Master Cylinder and Caliper”

  1. Jim Brown

    I installed a new front brake master cylinder, bled the brakes proceeded to take it for a test ride. About a block or two down the street my front brake locked up on me, so the wheel locked up, Any suggestions as to why and how to fix it?

  2. Richard Cole

    I rebuilt my master cylinder on 2000 HD ultra classic. I have bled the brake over and over. It will have brakes then start it. They work first time. Then not. I have to pump them to get any brake at all.?

  3. nelson45601

    I have a 2005 Deuce as my daily commuter. I started to notice my front brake getting harder to operate every morning until one morning the front wheel was completely locked up. I flushed out the break fluid and replaced it with new DOT 5 fluid (up to the fill mark) and all was well for a two days. Overnight the front brakes started stiffing up again and the only way to get them loose is to crack open the bleeder. How are the brakes locking up over night when she's not running? The indoor garage is always at 75 degrees.

  4. Edward

    i noticed i needed to replace my front brakes rt. side was only 1/2 worn on the left side outer was only 1/2 worn. but inner pad seemed to be doing all the work & the pad at a slight angle meaning the pad was not working freely it seems that where the pad pin goes it must be so tight that its not letting the pad work freely. if I bore the hole just a touch bigger 1/6 on the brake pad pin hole will that harm pad plate or my disc. thanks Edward