How to:
Shimano lever bleed
Difficulty
Beginner
Time taken
First time: 20 minutes
Thereafter: 5 minutes
Why bother?
Better brakes now
Save over $30 per end
What's the point?
Brake bleeding should be your go-to solution when you notice your brakes are:
• Spongey feeling
• Inconsistent feeling, sometimes called lever wander
Why do it yourself?
• Immediate need: Your brake is working poorly, but you want to ride now
• Simplicity: It's a straightforward process with minimal risk
• Cost savings: Shops charge $30-$70NZD per end and there can be a large wait
The lever bleed method is the fastest and simplest brake bleeding technique. If you are a beginner at bike maintanence, then a lever bleed is a great place to tstart. Follow the the procedure below and if you have any questions give us a shout 😊
Shimano Lever Bleed Procedure
You'll need the following items
• A large clean rag
• Isopropyl alcohol. We recommend getting a 1L bottle from your local hardware store
• Hex/Allen keys (2.5mm & 4mm)
• Mineral oil
• A bleed funnel for Shimano brakes. They are also included in our bleed kits:
➝ Shimano Basic bleed kit
➝ Shimano Premium bleed kit
Preparation: Store your bike vertically overnight
A lever bleed can only remove the air bubbles which are within your lever.
By storing your bike vertically overnight many of the bubbles will migrate to the lever so when you do your bleed, it will be even more effective.
Step 1: Cover rotor
Using a clean rag, cover your front rotor and caliper to shield it from any accidental drops of fluid.
It may seem unnecessary, but you'd change your mind if you got oil on your brakes... 😅
Step 2: Adjust Lever Angle
If your brake levers are angled downwards, loosen the clamp bolt, level the levers and re-tighten them. This is important for a lever bleed because bubbles won't be forced through with the fluid flow you get in a full bleed.
Step 3: Remove bleed screw
Using a 2.5mm allen key, carefully remove the bleed port screw, ensuring the o-ring also comes out.
Ensure the o-ring is on the bolt thread and put the bolt somewhere obvious and safe so that you don't lose it.
Step 4: Install Bleed Funnel
Install the bleed funnel. Make it tight enough to seal but not too tight, it's easy to damage the plastic threads of some bleed funnels.
Once sealed, remove the plunger.
Step 5: Add brake fluid
Pour a small amount of mineral oil into the bleed funnel. There needs to be enough so that the port from the funnel is submerged, we usually add at least 4mm depth of fluid.
Whatever you do, don't let fluid spill onto your brake pads. You can't rescue lubricated brake pads 😭
Step 6: Remove the pesky bubbles!
Squeeze and release the brake lever repeatedly until no more bubbles emerge. Keep a close watch on the bleed funnel's fluid level to ensure it doesn't run out.
You can encourage bubbles in the uppermost portion of your brake hose to move towards the lever by giving it a wiggle/tap.
Stop bleeding when bubbles have stopped coming out of your lever.
Step 7: Check lever firmness
Once the bubbles cease to appear, your brake lever should feel as firm or firmer than when you started.
If you're bleeding to make your brake more consistent, instead of less spongey, it may not feel any different.
Step 8: Seal and remove the Bleed Funnel
Install the plug back into the bleed funnel, and then carefully remove the bucket from the brake lever.
If this process has dirtied your fluid then don't put it back into the original container. If your fluid is dirty you should perform a full bleed whenever is next convenient
Step 9: Install Bleed Screw
Reattach the bleed port screw. Tighten it up until it feels firm but don't put too much torque on it, they're easy to damage.
Make sure the o-ring is on the screw otherwise it won't seal.
Step 10: Clean Brake Lever
Finally, apply some isopropyl alcohol, or a brake cleaner, to your rag and thoroughly clean the brake lever.
Types of bleeds
Lever (funnel) bleed
Short duration. The 80/20 of bleeds. It will get rid of most bubbles in your brakes. Seems a miracle if your brakes are bad.
Standard full bleed (caliper ➝ lever)
Long duration. The industry standard method of doing a full brake bleed. This will flush all bubbles out of the system and replace the fluid.
Reverse bleed (lever ➝ caliper)
Long duration. Our favourite method of doing a full bleed. It's like a standard full bleed but will remove all of the heaviest particulates in your fluiid too.
We plan to offer tutorials for these kinds of bleed too, so watch this space 😊