Hope M4 Lever Overhaul & Bleeding

Use a 10mm spanner to loosen the hose bolt (21) then remove the two bar clamp bolts from the lever. When the lever is free from the handlebar, unscrew it all the way from hose (24). Wrap a lttle tissue around the joint to catch the dribbles (22). Note the copper washer (23).

Use an 8mm spanner/socket and a 3mm allen key to remove the lever pivot bolt/nut (25), and a 2mm allen to remove the lever piston pin (26). NB Turn CLOCKWISE to remove the pin from the brass barrel (27).

The piston seal is held in place with a retaining clip. This can be carefully prised out with a small jewellers screwdriver (28) or use the circlip pliers.

The piston assembly is sprung, and held in place with a brass washer and a circlip (29). You will need a set of circlip pliers to remove/replace this circlip (30).

With the circlip removed the pin and washer can be pulled out (31)(remember it’s under a small spring load).

Use a soft/round tipped tool to poke the piston assembly through and out of the lever body. Do not use a screwdriver. A 3mm ball-end allen key is ideal (32)

Picture (33) shows the full lever assembly. Take note when you remove the piston which way the two piston seals sit. I they are fitted the wrong way around they will not function.

If your brake levers have some slop in them, you can put a small washer on top and on bottom of connection point inbetween the body and the lever.

, Hope M4 Lever Overhaul & Bleeding

, Hope M4 Lever Overhaul & Bleeding


, Hope M4 Lever Overhaul & Bleeding

Wear safety glasses

1. Remove the wheel and brake pads to prevent contamination
2. Push the caliper pistons back into their bores and insert a spacer between the pistons to prevent them coming out during the bleed operation. (spacer is 11.5mm, pic.20)
3. If necessary reposition the brake lever so that the lever and master cylinder is horizontal to the ground.
4. Remove the master cylinder cap using a 2mm allen key (2.5mm on the newer, flat-top bolts). Then remove the rubber diaphragm.
5. Place the closed end of an 8mm spanner over the bleed nipple on the brake caliper. Fit a length of clear plastic hose (approximately 30cm) onto the bleed nipple and place the free end into an empty container. The hose should be a snug fit and not fall off, the free end does not need to be submerged under brake fluid.
6. Fill the master cylinder reservoir with brake fluid.
7. Open the bleed nipple a ¼ turn. Slowly pull the brake lever to the handle bars and hold. Close the bleed nipple. Release the lever. Caution, squeezing the lever too fast will cause brake fluid to squirt out of the master cylinder.
8. Repeat step 8 until no air is seen coming out of the bleed nipple. You will need to keep filling the reservoir during this operation. Caution, if bleeding a rear brake be careful not to spill brake fluid onto the front caliper and disc.
9. Ensure the pistons are fully retracted in the caliper, the pistons may require manually pressing back.
10. Place a rag around the master cylinder to catch any spillage and fill the master cylinder to just below the top surface (36).
11. Place the diaphragm into the master cylinder and allow the fluid to overflow (37). Close the bleed nipple and remove the bleed hose. Caution, do not over tighten the bleed nipple. Wipe away any spilt fluid from the caliper and lever.
12. Fit the master cylinder cap and gently tighten with a 2mm allen key (2.5mm on the newer, flat-top bolts). Caution, do not over tighten cap as you are only sealing the rubber diaphragm (38) (At this point you may want to refresh your pads. Trace a figure 8 on a piece of 100ish sandpaper until the pad surface is evenly cleaned/deglazed (39)
13. Replace the pads (40) and insert the wheel. Pull the lever several times to allow the pads to reset themselves to the disc.
14. Check the brake for correct function and that there are no system leaks.

Here’s what Hope has to say about bedding your pads in;

” To achieve the maximum braking effort the new brake pads need bedding in. Bed in the
pads by riding a short distance with the brake applied, it also helps to pour clean water over the
caliper and pads whilst bedding in. This procedure will achieve good braking performance but will reach its full potential after a few rides.”

In addition to this, I’ll get up a head-of-steam before pulling hard on the brakes, then pour cold water over the caliper/pads. A mixture of the two has my brakes biting nicely after around 15mins.

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