Differences

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--- techtalk:ref:wheels03a [2019/04/17 17:44]
hippysmack [Master cylinder issues]
+++ techtalk:ref:wheels03a [2019/04/22 02:33]
hippysmack removed
@@ Line 48: / Line 48: @@
 ===== Using a Syringe =====
-  * The key to this method is a slow push from the caliper to the master cylinder. Too fast and you spit brake fluid all over the bike and the floor.
+The key to this method is a slow push from the caliper to the master cylinder. \\
-  * The handle end of the master cylinder must be higher than the hose end so the air bubbles will move to the relief port of the master cylinder. ((ryder rick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1025390&highlight=Brake+Fluid+Bleeding+w%2FSyringe))
+Too fast and you spit brake fluid all over the bike and the floor. \\
-  * You can also use a squirt type oil can with some rubber tubing on the spout slipped over the cracked-open bleeder. ((chopfather of the XLFORUM http://xlforum.net/forums/showthread.php?t=33235&page=3))
+The handle end of the master cylinder must be higher than the hose end so the air bubbles will move to the relief port of the master cylinder. ((ryder rick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1025390&highlight=Brake+Fluid+Bleeding+w%2FSyringe)) \\
-  * Or, you can use a turkey basting syringe and a foot of rubber hose.
+You can also use a squirt type oil can with some rubber tubing on the spout slipped over the cracked-open bleeder. ((chopfather of the XLFORUM http://xlforum.net/forums/showthread.php?t=33235&page=3)) \\
+Or, you can use a turkey basting syringe and a foot of rubber hose.
   - Discard the needle from the syringe, remove lid from master cylinder and re-set it on top. \\ It must be off of course, but the master cylinder must be covered to prevent the fluid from squirting 10' across the shop. ((IronMick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1489822&highlight=Brake+Fluid+Bleeding+w%2FSyringe))
@@ Line 309: / Line 310: @@
 ===== Before bleeding =====
-  * **Before attempting to bleed the lines**;
+==== Before attempting to bleed the lines ====
     * Remove the M/C top, actuate the pedal / lever and make sure you can see a bubble in the center to make sure the M/C is working.
       * Pump hard on the brake pedal lever. You should see a small buble as mentioned above.
@@ Line 320: / Line 322: @@
     * When you crack the bleeder valve, only turn it a 1/4 turn or so. ((DaytonaSportster of the XLFORUM http://xlforum.net/forums/showthread.php?t=1637840&page=2)) \\  Any more and you will get air from around the threads. \\ Also if you're using a vac, make sure it's not leaking where you attach it to the bleeder nipple.
-  * **How the master cylinder transfers fluid**:
+==== How the master cylinder transfers fluid ====
     * The downstroke, pushing the pedal / pulling the lever, forces (only) what's in the lines already into the hose. ((Hippysmack of the XLFORUM http://xlforum.net/forums/showthread.php?p=5740029#post5740029)) \\ Releasing the pedal (pedal at rest) is what adds fluid into the lines from the M/C reservoir.
     * The compensation port (from the reservoir) sits just in front of the main plunger seal. \\ The lever has to fully retract or the port get's blocked off by the seal.
@@ Line 331: / Line 334: @@
 |{{:techtalk:ref:wheels:master_cylinder_cutaway_1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:wheels:master_cylinder_cutaway_2_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:wheels:master_cylinder_cutaway_3_by_hippysmack.jpg?direct&300|}}|
-  * **Notes regarding brake fluid**: \\
+==== Notes regarding brake fluid ====
-    * Paint peel-ability of different fluids: \\ DOT 3,4 & 5.1 can peel the paint on frame and other painted parts. \\ DOT 5 is silicon based and will not peel the paint. \\ You can spill DOT 5 brake fluid virtually anywhere and harm nothing. ((IronMick of the XLFORUM http://xlforum.net/forums/showthread.php?t=867917&page=2))
+Also reference the [[techtalk:ref:wheels03#brake_fluid|Brake Fluid]] article in the REF section of the Sportsterpedia for type per year model, specs, mixing fluids etc. \\
-    * **Caution**: \\ Do not mix DOT 5 with (DOT 3,4 or 5.1) \\ Also reference the [[techtalk:ref:wheels03#brake_fluid|Brake Fluid]] article in the REF section of the Sportsterpedia for type per year model, specs, mixing fluids etc. \\
+  * **Make sure you do regular brake fluid changes according to the FSM change intervals**. \\ If the bike has sat for a long period of time, it's best to go ahead and plan on changing both front and rear.
+  * **Paint peel-ability of different fluids**:
+    * DOT 3,4 & 5.1 can peel the paint on frame and other painted parts. \\ DOT 5 is silicon based and will not peel the paint. \\ You can spill DOT 5 brake fluid virtually anywhere and harm nothing. ((IronMick of the XLFORUM http://xlforum.net/forums/showthread.php?t=867917&page=2))
+  * **Caution**:
+    * Do not mix DOT 5 with (DOT 3,4 or 5.1)
+|  Note the gooey mess from mixing Dot 5 and Dot 3 fluids. ((photos by FearlessFrisbee of the XLFORUM http://xlforum.net/forums/showthread.php?t=1508535))  ||
+|{{:techtalk:ref:wheels:dot_5_-_dot_3_mix_goop_1_by_fearlessfrisbee.jpg?direct&300|}}|{{:techtalk:ref:wheels:dot_5_-_dot_3_mix_goop_2_by_fearlessfrisbee.jpg?direct&300|}}|
+  * **DOT 3,4,and 5.1 can dry up over time**:
+    * Any type brake fluid can break down over time, solids fall out of suspension and clog up orifices.
+    * However, DOT 3, 4 and 5.1 will mix with water and they will dry up as water does over time.
+    * Look for corrosion in the aluminum in addition to the goo. \\ It's caused by the fluid absorbing water when the bikes sit for a long time and or the fluid is not changed for a long time. \\ Too long and you may find pits in the body of the MC and / or bore pitted beyond being cleanable with a hone. ((FearlessFrisbee of the XLFORUM http://xlforum.net/forums/showthread.php?t=1509571))
+|  Affects of dried up DOT 3 brake fluid. ((photos by Daddio of the XLFORUM http://xlforum.net/forums/showthread.php?t=1509571))  ||
+|{{:techtalk:ref:wheels:dot_3_dried_up_1_by_daddio.jpg?direct&300|}}|{{:techtalk:ref:wheels:dot_3_dried_up_2_by_daddio.jpg?direct&300|}}|
+==== Notes regarding brake lines ====
-  * **Notes regarding brake lines**: \\
     * Take the trash out. \\ Check the M/C, calipers and lines to make sure they are free from debris or sludge. \\ Old brake fluid will break down and solids will fall out of suspension and block passage ways.
     * Old rubber brake lines may get weak from the inside. \\ This can cause them to bulge at the weak spot and not send pressure to the caliper. \\ It's sort of like a baloon being inflated. ((jharback of the XLFORUM http://xlforum.net/forums/showthread.php?t=1637840)) \\ It doesn't do it normally enough to be noticed (but enough to drive you crazy trying to track the problem down). \\ Just keep an eye on them while actuating the lever / pedal.
-  * **Lever / Pedal**: \\
+==== Lever / Pedal ====
     * Make sure the piece that hooks up to the actual lever that controls the brake is adjusted correctly. \\ It makes a considerable difference in the function of the M/C. ((DIESEL of the XLFORUM http://xlforum.net/forums/showthread.php?t=91538&page=2))
-  * **Check for leaks**. \\
+==== Check for leaks ====
     * If you pull the cap off the M/C and the reservoir is very low or dry, that usually points to a leak somewhere. ((Deimus of the XLFORUM http://xlforum.net/forums/showthread.php?t=91538)) \\ Possible, even if you could bleed it, there is still a problem that you should take care of. \\ Before you can build pressure, the system has to be leak free. \\ (this is especially important when changing lines / components) \\ Gussers will be obvious. But weeping leaks may be harder to detect in a fast visual scan.
     * **There is no reason to use Teflon tape on any brake connections**. \\ If you want to seal the threads on the bleeder screw (normally unnecessary with conventional bleeding) try greasing the threads first. \\ Teflon tape can get sucked into and stop up the orifices (especially on flared fittings).
-  * **Trapped air**: \\ Trapped air that refuses to leave will drive you crazy trying to find it.
+==== Trapped air ====
+Trapped air that refuses to leave will drive you crazy trying to find it.
     * **Brake fluid**: \\
       * When DOT 3, 4 or 5.1 fluids trap air, the smaller bubbles can migrate and come together to form bigger bubbles that are fairly easy to remove. ((Gold951 of the XLFORUM http://xlforum.net/forums/showthread.php?t=53378&page=2))
-      * When DOT 5 fluid traps air, the bubbles have some difficulty migrating, so the bubbles tend to be smaller and there are more of them. \\ Also, when you pressurize a DOT 5 brake system that has trapped air and then let the pressure off; \\ The DOT 5 fluid tends to break the original bubbles into even smaller and smaller bubbles. \\ What you end up with is a brake fluid that has lots of microscopic air bubbles and your brakes feel spongy. \\ DOT 5 holds stupid amounts of air and you'll get no lever until its out (or at least most of it). ((cantolina of the XLFORUM http://xlforum.net/forums/showthread.php?t=33736))
+      * When DOT 5 fluid traps air, the bubbles have some difficulty migrating, so the bubbles tend to be smaller and there are more of them. \\ Also, when you pressurize a DOT 5 brake system that has trapped air and then let the pressure off; \\ The DOT 5 fluid tends to break the original bubbles into even smaller and smaller bubbles. \\ What you end up with is a brake fluid that has lots of microscopic air bubbles and your brakes feel spongy. \\ DOT 5 holds stupid amounts of air and you'll get no lever until its out (or at least most of it). ((cantolina of the XLFORUM http://xlforum.net/forums/showthread.php?t=33736)) \\ You may find that re-bleeding the caliper every couple of days will eventually get you a hard pedal for awhile. ((sportsterpaul of the XLFORUM http://xlforum.net/forums/showthread.php?t=1632435&page=3))
     * **Calipers**. \\ Sometimes small air bubbles get stuck in the caliper.
       * Try removing the caliper (M/C cap off) and pressing in the piston which will force fluid / air up into the master. ((iNSaNeSHaNe of the XLFORUM http://xlforum.net/forums/showthread.php?t=2070555&highlight=m%2Fc))
@@ Line 426: / Line 449: @@
 A syringe can be used to reverse bleed from the bleeder valve to the caliper. \\
 The syringes needed are the big ones (not an injection syringe as you'd normally see used in medical applications). \\
+A 60 ml (2 oz) syringe is just the right size. That is about the amount that will fill the master cylinder and the line. ((IronMick of the XLFORUM http://xlforum.net/forums/showthread.php?t=295754&page=2))
   * Sources for syringes:
@@ Line 447: / Line 471: @@
     * Once this process is done, install the M/C, hook up your actual brake lines and continue bleeding at the caliper bleed screw.
 ===== Master cylinder issues =====
-  * If none of the methods below work for you; \\ You may either have a leaking compression fitting, \\ The cup in the master cylinder is blown out, \\ Or the big O-ring in the caliper is not sealing against the piston. \\ Those are the only three places for air to enter the system. ((wedge of the XLFORUM http://xlforum.net/forums/showthread.php?t=1062732&highlight=Brake+Fluid+Bleeding+w%2FSyringe&page=2))
+  * **Note**:
-  * If it is a brand new master cylinder and it is not squirting hard when you have the hose disconnected, \\ You might have a faulty Taiwan Trash master cylinder. ((Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?t=857384)) \\ If none of the bleeding suggestions below work, try putting your old master cylinder back on. \\ Sometimes, you'll end up with a new aftermarket master cylinder that doesn't work. \\ The seals have been known to be jammed in cockeyed from the manufacturer.
+    * Bleeding air out of a Sporty master cylinder can be a frustrating task.
+    * Before suspecting the master cylinder, make sure you've exhausted your bleeding options before rebuilding the M/C for no reason.
+    * While fresh seals is never a bad idea;
+      *There has been a number of unnecessary rebuilds. \\ (when the rebuild simply allowed time or convenience for the air to be expelled).
+  * **Clean the hole(s) in the bottom of the master cylinder**:
+    * The transfer hole(s) can get clogged from debris or solids that drop out of suspension in the fluid itself. \\ Clear them with a pin, a bristle from a wire brush, welding tip cleaner or other or the master cylinder will not transfer fluid properly.
+    * The holes can be plugged up solid yet still look like there is nothing in them. ((Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?t=295754&page=2))
+  * **If none of the methods below work for you**; \\ You may either have a leaking compression fitting, \\ The cup in the master cylinder is blown out, \\ Or the big O-ring in the caliper is not sealing against the piston. \\ Those are the only three places for air to enter the system. ((wedge of the XLFORUM http://xlforum.net/forums/showthread.php?t=1062732&highlight=Brake+Fluid+Bleeding+w%2FSyringe&page=2))
+  * **If it is a brand new master cylinder and it is not squirting hard** when you have the hose disconnected, \\ You might have a faulty Taiwan Trash master cylinder. ((Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?t=857384)) \\ If none of the bleeding suggestions below work, try putting your old master cylinder back on. \\ Sometimes, you'll end up with a new aftermarket master cylinder that doesn't work. \\ The seals have been known to be jammed in cockeyed from the manufacturer.
   * A plugged or covered relief port can cause brake drag or locking of the brakes.
   * **The 04-up rear master cylinder is well noted for a split primary cup**. (((Wedge of the XLFORUM http://xlforum.net/forums/showthread.php?t=1643503&page=2))
-    * It seems to regularly rear it's ugly head when you replace the rear tire, but there is no connection. ((wedge of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452&page=8))
+    * It seems to regularly rear it's ugly head when you replace the rear tire or compressing the rear caliper piston, but there is no connection. ((wedge of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452&page=8)) ((sfxtech of the XLFORUM http://xlforum.net/forums/showthread.php?t=75157))
       * What seems to happen is that the primary cup gets torn in the center and it manages to still work as long as the MC is not disturbed much. \\ (since it is backed up with that flat metal plunger which helps it seal even though broken)
       * **Symptoms include**:
-        * Loss of brake pressure and then it's regained as you ride. ((CBAS5 of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452)) \\ Or, you may 'feel' something different with the brake pedal but the brakes may still function just fine.  ((devilswild66 of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452))
+        * Loss of brake pressure and then it's regained as you ride. ((CBAS5 of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452)) \\ Or, you may 'feel' something different with the brake pedal but the brakes may still function just fine.  ((devilswild66 of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452)) \\ Another account: \\ "Felt like there was air in the system, but a few pumps on the pedal and I could ride for a day or two until the pedal got low again". ((vferdman of the XLFORUM http://xlforum.net/forums/showthread.php?t=75157&page=3))
         * Spongy brake pedal. ((Hot Rod Sporty of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452))
         * Complete loss of brake pressure not to be regained.
@@ Line 465: / Line 498: @@
       * The rebuild is an extremely easy job as long as you have a good set of retaining ring pliers. \\ If you loose the retaining ring that holds the master cylinder plunger to the bell crank, it is a 1/4". ((klinesamuel of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452&page=5))
-|  Pics of the 04+ split primary cup issue. ((photos by devilswild66 of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452))  |||
+|  04+ split primary cup. ((photo by sfxtech of the XLFORUM http://xlforum.net/forums/showthread.php?t=75157))  |  M/C rebuild kit (42830-05) ((photo by sfxtech of the XLFORUM http://xlforum.net/forums/showthread.php?t=75157))  |
+|{{:techtalk:ref:wheels:damaged_rear_m-c_primary_cup_by_sfxtech.jpg?direct&300|}}|{{:techtalk:ref:wheels:04_up_m-c_rebuild_kit_by_sfxtech.jpg?direct&300|}}|
+|  More pics of the 04+ split primary cup issue. ((photos by devilswild66 of the XLFORUM http://xlforum.net/forums/showthread.php?t=65452))  |||
 |{{:techtalk:ref:wheels:master_cylinder_torn_primary_cup_1_by_devilswild66.jpg?direct&300|}}|{{:techtalk:ref:wheels:master_cylinder_torn_primary_cup_2_by_devilswild66.jpg?direct&300|}}|{{:techtalk:ref:wheels:master_cylinder_torn_primary_cup_3_by_devilswild66.jpg?direct&300|}}|