Say you trashed your race bike in practice and had to borrow one for your race run - but the front brake is on the left and you ride moto style. Time is a ticking. Do you risk missing your start time and bleed the brakes, or is there another way? In this Ghetto Tech Tuesday we show you a method used to switch brake hoses left to right at the levers which, in all but a few cases, eliminates the need to bleed the system. The trick is to remove the wheels, pump fluid from the lever's reservoir into the caliper, switch the hoses, and then replenish the fluid into the reservoir and evacuate any air bubbles by spreading the brake pads. The technique is frowned upon by brake makers, but it can get you back into the game in a pinch.
Note: If your brakes can be flip flopped (like the Avid Elixirs used in this demonstration), then it makes no sense to switch hoses - just unscrew the perches and flip the lever assemblies. Pre 2012 Magura brakes do not have enough reserve fluid in the lever's reservoir to execute this procedure. We have successfully used the following technique on Shimano, Avid, Formula and Hayes. Danger:
This is a temporary technique to switch hoses in a pinch. If you complete this procedure and the levers feel soft or less than firm and responsive, you'll need to properly bleed the air from the system before riding the bike. Always check to ensure that the brakes are functional and that the levers feel firm when squeezed repeatedly BEFORE you ride and then do a trial ride to ensure that the system is working before setting out into the real world. Some brake fluid is usually lost in the process. After your ride, check the fluid levels in the master cylinder reservoirs, or give the system a proper bleed.
What You'll Need:
The only major tools you'll need are a clean, flat-bladed screwdriver and an eight-millimeter open-end wrench.
• A clean towel to wipe brake fluid from the lever and to protect the floor.
• Eye protection is always important when dealing with compressed fluids.
• An eight millimeter open end wrench.
• A clean, flat-bladed screwdriver.
How to Switch Hoses Without Bleeding Your Brakes
Step 1 -Remove the wheels and hang the bike by the saddle, or put it in a stand.
Step 2 -Pump the brake levers until the pads close as far as they will go. There will probably be about a one-millimeter gap between the pads.
Step 3 -Slide back the protective rubber housing to expose the compression nuts. Loosen both sides with an eight-millimeter open-end wrench.
Step 4 -Unscrew both of the compression nuts by hand and pull the hoses free from the levers. Quickly switch the hoses and then thread the compression nuts in hand-tight.
Step 5 -Tighten the compression nuts snugly (don't overdo it), wipe off any spilled fluid with a towel and then replace the rubber caps.
Step 6 -Using a clean, flat-bladed screwdriver, carefully pry the brake pads apart until they are completely retracted. This should push the bubbles out of the line and into the master cylinder reservoir.
Step 7 -Replace the front and rear wheel. Secure the axles to the maker's specifications.
Step 8 -Pump the brake levers to reset the pads against the rotors. The levers should feel firm. If a lever feels springy, there is air trapped in the system. Pull the wheel out, spread the pads again, install the wheel and repeat. No? Then bleed the brake properly before riding. Test ride the bike in a safe environment to ensure the brakes are functional before setting out.