Home Bike Repair – Bleed Your Rig’s Binders

An empty pop bottle, a bent up coat hanger and a cheap pump oil can has served as the budget brake bleed kit of choice for do-it-yourself riders for quite some time, but those cheap pump oil cans are hard to get the air out of, so bleeding your brakes that way can lead to frustration and a waste of fluid. Another alternative of course is to drop by your local bike shop and have a mechanic do the work for you, or you can pick up a manufactured brake bleed kit and achieve the same result repeatedly, saving you money.Maintaining the proper volume of clean and air free fluid is the most important thing in your juice brake system. The relatively uncompressible fluid transmits and multiplies the force supplied by your digits to the brake rotor – add dirt and a bit of compressible air however, and your brakes will not perform correctly or will fail altogether. Occasional fluid changes are required to keep your brake system clean and air free, something the home bike mechanic can achieve without much talent.
Here’s how it worked for me using the Little Leech Pro brake bleed kit manufactured by Plush Products for the Hayes disc brake system:


Note: Plush Products are unfortunately now out of business, their comprehensive kit was arguably the best available since it included a syringe instead of a plastic squeeze bottle to supply clean fluid to the system, it also came with an enclosed dirty fluid bottle for the other end, oddly enough some manufacturers are either too cheap or too short sighted provide either.


Before you start it’s a good idea to throw on a pair of safety glasses, there are much better things to have in your eyeball than brake fluid, and avoid spilling DOT type fluid on your frame or fork, it will quickly remove the paint from these surfaces. Speaking of which, make sure that you purchase the correct fluid for your system as specified by the manufacturer (for instance some brake systems use mineral oil). Using the wrong fluid can lead to failure of the brake system as the internal seals may react unfavourably to the fluid causing them to swell and break down. It’s also advisable to place the bike in a stand and remove the wheel and brake pads to prevent the spilling of fluid on the brake pads or rotor. Lacking a stand and having bled brakes before, I elected not to do so. DOT brake fluid spilled on any surface can be cleaned with Isopropyl alcohol, though contaminated brake pads must be replaced.

1 – If you need to, use an Allen key to loosen the brake lever of the brake that you want to bleed and rotate the lever so that it’s upright.

2 – Using a number 1 Phillips screwdriver, remove (but don't lose) the bleed screw with rubber washer attached from the bottom of the reservoir, now facing the top.


3 – Insert the hose into the opening that the screw occupied and secure the discharge bottle to the handle bar near the brake lever, in this case using an included Velcro strap. Put the other end of the hose in the bottle. If your kit didn’t include a bottle and hanger strap, the trusty pop bottle and bent coat hanger will have to do.


4 – Now take the syringe and place the hose in the new and sealed bottle of brake fluid. Pull the plunger up and draw the syringe full of fluid taking care not to pull the plunger all the way out. In the case of other brake bleed kits fill the clean fluid squeeze bottle with brake fluid, or better yet do yourself a favour and get a syringe from a medical supply store, it’s a lot less messy.


5 – Hold the full syringe upright (the hose pointing up) and insert the hose into the bottle strapped to the handle bars and depress the plunger just enough to expel the air from the syringe.


6 – Remove the rubber cap from the brake calliper bleed nipple and with the syringe or squeeze bottle held upright (hose pointing down) to keep any remaining air at the plunger end of the syringe or top of the squeeze bottle, carefully work the hose over the end of the bleed nipple.


7 – With an eight-millimetre wrench slightly loosen the bleed nipple (a quarter turn is enough) while depressing the plunger or squeezing the bottle. Fluid will begin to flow from the syringe or bottle, through the calliper and hose to the reservoir and out to the bottle on the handle bar (watch the discharge hose as the fluid flows to the bottle on the handle bar for air bubbles and dirty fluid).


8 – When sufficient fluid has passed through the system and no more air and dirty fluid are found, close the bleed nipple on the calliper while still pressing down on the plunger or squeezing the bottle. In the case of the Little Leech bleed kit, the syringe holds enough clean fluid to clear the system, though you may need to repeat the procedure if you still have dirty fluid flowing out the hose at the reservoir.


9 – Remove the syringe or squeeze bottle and place the rubber cap at the calliper bleed nipple. Remove the hose and dirty fluid bottle from the bar and carefully replace the screw in the reservoir. Don’t over-tighten the screw; wind it in just enough so that the rubber washer begins to crush.

10 – Pull your brake lever back into its normal position and tighten it up. Your lever should be left tight enough to stay in place but loose enough to rotate on the bars to prevent damage to the lever or reservoir in the event of a crash.

11 – Put the caps back on the bottles and dispose of the used fluid properly, and never re-use old fluid no matter how clean it may appear to be.

The next time out on your ride make sure that you check for leaks and test your brakes at slow speed on easy terrain before you hit the trail.


There’s nothing worse than making the trip out to your favourite place to ride only to find that your brakes need bleeding, it’s worth while packing your bleed kit around with you in your tool kit for that emergency brake bleed when you need it.
Visit your local bike shop, preferably the one that sold you the bike or the brake, for the proper bleed kit for your bike's system.

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