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Within the past few months I’ve started to notice oil on the main lever pivots of the Shimano SLX (BL-M7000) brakes on my Salsa Mukluk and the brakes have started to feel like they need a bleed. It was recommended that I try rebuilding them — cleaning them out and re-greasing the seals — before replacing.

Using some Danco Silicone Faucet Grease and following a couple of YouTube videos to understand the teardown process I was able to easily get both levers apart and back together, and after my first test ride they seem to be working great. I believe these were getting dirty after a few years of exposure to all sorts of conditions and the seals needed a bit of freshening up. (In this design the end of the piston and thus a thin piece of seal is exposed to the elements.)

The overall process was quite straightforward, and between these two videos (1, 2) I had no problems figuring out what to do. While the first video is a bit dark, the subtitles helped tremendously. The second is in Tagalog, but shows the process clearly. EV-BL-M7000-3978.pdf, Shimano’s exploded view of the lever, is also somewhat helpful but does not show the details of the piston nor the push rod. If you are reasonably mechanically inclined, and can work with small parts, you’ll have no problem.

Here’s the major steps, along with notes. These steps apply to both the BL-M7000 (SLX) and BL-M8000 (XT) levers and are likely applicable to other similar levers. I recommend that you do levers one at a time, or take photos as you go, to see how the parts fit together. The lever return spring is particularly fiddly to get into place and it’s location is not immediately obvious during reassembly.

Disassembly:

1. Disconnect brake hose and remove lever from bar.
2. Remove bleed port, squeeze lever a few times to drain excess oil.
3. Remove the small rubber plug which covers the set screw holding the pivot pin (Lever Axle, #5 on EV) in place. Back out but do not remove this set screw (Lever Axle Fixing Bolt and Cap, #4 on EV).
4. Press out pivot pin from underside using a 3mm hex wrench or rod to remove the lever. (I had to use a small hammer to loosen it as it was stuck in place.)
5. Locate the T-shaped ball-end shaft which presses on the piston. Remove with a twisting motion on the head, snapping it into or out of the plastic guides.
6. Locate the plastic pivot plate which has a hooked bottom for the pad contact adjust lever. Remove this; loosen by pushing it out via the holes in the lever body.
7. Remove the pad contact adjust lever, which the pad contact adjust screw presses against. (This screw exists on both XT and SLX levers, although it’s externally blanked on SLX.) Depressing the piston with a ball end hex wrench and lifting the lever out with smooth jaw needle nose pliers makes this easier.
8. Use a thin rod, such as a 3mm wrench, to push the piston and spring out via the brake hose end. Be careful not to mar the mirror-polished brake piston bore.
9. Remove the other plastic pivot plate.

Cleaning:

1. Wipe down the brake lever body to remove oil and gunk. Clean out the inside of the bore with a paper towel, being careful not to damage the mirror polish. I do not suggest submerging or using soap or degreaser as it’ll be difficult to clean out the reservoir half of the lever.
2. Gently wipe off the piston and spring. Inspect the seals for damage. If they are damaged, you’ll need to find a new piston as these are key to the brake working and not leaking.
3. Clean the lever and reach adjustment. (I used dish soap and a paintbush.)
4. Clean the lever return spring. Do not bend this.
5. Clean the plastic guide plates, being sure to not scratch the them.
6. Disassemble and clean the T-shaped ball-end shaft. There are two small plastic caps, a bushing, an axle, and the ball end shaft. Take care of the plastic end caps, these slide in the guide plates to make everything work.

Reassembly:

1. Reassemble the T-shaped ball-end shaft putting a bit of silicone grease in and on the bushing, in and on the plastic end caps, and on the ball end.
2. Fit the pivot plate without the hooked bottom.
3. Drop the spring into the brake lever.
4. Apply a very thin film of silicone grease to the piston and drop it into the lever with the concave end facing out.
5. Replace the pad contact adjust lever while gently holding the piston in with a tool.
6. Fit the other pivot plate, with the hooked bottom, into place with the hooked bottom fitting around the pad contact adjust lever.
7. Replace the T-shaped ball end shaft with a twisting motion that allows the end caps to it follows the ramps on the pivot plates.
8. Partially insert the pivot pin into the lever.
9. Fit the lever return spring between into the lever between the main lever blade and reach adjust.
10. Align the pivot pin holes in the lever with the spring, with the lever pressing against the bushing on the T-shaped ball end shaft, and slide the pivot pin into place. (This was easiest when I guided the assembly together with a 3mm hex wrench.)
11. Tighten the set screw to hold the pivot pin in place.
12. Check that the lever moves and returns smoothly. Assess and fix if not.
13. Turn the reach adjust for maximum reach. Reattach hose and bleed system.

The Bontrager Line Dropper Seatpost, as fitted on Kristen’s Trek Fuel EX 9.8 Women’s (mirror) is a quality dropper, and I’m particularly impressed with the way built-in sacrificial parts fail when the saddle is hit hard from the side. Over the summer Kristen has had a couple crashes which, due to hard impacts on the side of the saddle, damaged the dropper. After the first crash the saddle (and inner part of the dropper) would turn easily to one side, and after the second the saddle had a bunch of side to side play, and could be turned to the side fairly easily.

On this dropper there are two plastic keys that slide in grooves in the outer tube as the saddle moves up and down. They keep the saddle from moving to the side, are designed to fail when the saddle is hit hard from the side. By using a sacrificial part like these plastic keys, Trek/Bontrager’s designers have a dropper which works well, but only costs a few dollars to repair after a damaging crash.

The key set, part number 572184 and $5.99 MSRP, is replaced by removing the seatpost from the bike, unscrewing the bottom of the post by hand, then unscrewing the retaining ring at the top of the post with a strap wrench. Sliding off the outer tube reveals the keys, which can be popped out with a pin or a razor blade. Wiping everything down, fitting the replacement keys in the groove, lubing with Slickoleum, then putting everything back together is all that’s needed to repair the dropper to like-new condition.

The photo above shows a pair of damaged keys, along with the plastic shavings cleaned out of the dropper after a failure. The rounded edges on the keys show where they fail when overloaded, and the shavings are the remains of the once-sharp edges.

I’m really happy with this dropper. It works well, it’s overall pretty cheap, is easy to disassemble to repair after a crash, and replacing the main cylinder should be just as easy, whenever it comes time for that.

Crankbrothers Eggbeater and Candy pedals have been my go-to for years, performing admirably year-round.

All Crankbrothers pedals require periodic maintenance in the form of the Pedal Refresh Kit, which replaces the bushings and bearings and gets them spinning like new. The cleats — made of brass — wear out as well and require replacement roughly once a season, along with the required-for-carbon-soles Shoe Shields.

Unfortunately, there is one kind of wear which puts the pedal near the end of its life: pedal wing wear. Above you can see the pedal wings on the Eggbeater 3 pedals from my Specialized Camber, which worn to a point.

The wings are normally box shaped, providing a nice even load on the cleat and sole of the shoe. After wearing to a point the cleat and Shoe Shield wear are accelerating, to the degree that my cleats have worn out mid-year instead of late autumn.

With all this wear put together, pedaling my Camber felt a bit vague and I’d get squeaking and clicking sounds from the pedals when putting down a lot of steady power. Flipping the pedals 90° to change up the engagement would help, as some of the wings are worn less than others, but it’s now time for the pedals to go.

(Instead of replacing with new Crankbrothers pedals I’m giving Shimano PD-M8100 (Deore XT M8100) SPD pedals a go. I’m hoping the larger contact area between the cleat, pedal, and shoe lugs will help with some foot pain problems I’ve had during longer rides. I also expect cleat replacement will be less frequent, costing less long-term. I have concerns about how well SPDs will clear snow and/or permit very fast exit when suddenly stopping on technical sections, so I won’t be selling off my remaining Eggbeaters any time soon.)

It seems the design of the bleed nipple on Shimano hydraulic disc brakes may result in contamination of the brake pads if extra care isn’t taken to clean residual oil from inside the nipple after bleeding the brakes. Newer Shimano hydraulic calipers, such as the Shimano BR-M7100 (SLX), have this nipple facing downward when installed on most bikes which seems to exacerbate the issue.

After following the Shimano brake bleed procedure and disconnecting the hose, the nipple will still contain about 0.06 mL of brake fluid, roughly a full drop, closed only by a snap-fit rubber cap. (See exploded view, inside of nipple is ~20mm x ~2mm ⌀.) On many brakes, including the BR-M7100 when mounted to a fork or seatstay, the nipple points downward and the residual oil inside slowly weeps out, wetting the outside of the cap and the caliper. Particularly after mixing with dust and forming an oily paste this can fling to the rotor or pads, contaminating the pads, leading to poor performance and noise.

On other Shimano brakes, such as the the BR-M8000, the bleed nipple is on the other end of the caliper. These point up and don’t seem to weep residual oil as readily. However, because bikes are stored and transported in a variety of positions, much less bounced all over the place while riding, any oil in the nipple can cause escape.

To avoid self-contamination it’s necessary to remove all residual oil from inside of the bleed nipple after a bleed. This can be done by twisting the corner of a paper towel into a point, shoving it into the nipple, and blotting the oil up. A couple iterations of this and thorough cleaning of the caliper and inside of the nipple with isopropyl alcohol seems sufficient. After doing this the nipple caps on our bikes have remained dry.

I came to this realization after a handful of dusty rides on the Timberjack when I noticed this cap had a bunch of dark oil-soaked dust on it. A quick check showed the inside of the cap was quite oily. There was also a thin film of oil wicking on to the bleed nipple and caliper body. As the bike is nearly new the brakes had recently been bled and the outside of the calipers thoroughly cleaned, it all fit together. (I suspect this may have led to the contamination problems I had earlier with the pads, although those pads themselves seemed bad from the get-go.)

On Kristen’s fatbike — a 2018 Specialized Fatboy Carbon Comp which received M7100 SLX brakes to replace the failed SRAM Level TLs but has only been kept upright since the brake install — the front brake whose nipple points down had oil in the cap. The rear brake, mounted to the chainstay and pointing the nipple up, was dry, but still had visible oil in the nipple.

This could also explain a mysterious fouled-front-brake problem on my Warbird, whose BR-R7070 (105) calipers have a downward facing bleed port on the front and upward facing on the rear. This was fixed with a sanding of the rotor and pad replacement, but I could not find a source of oil and the system seemed sealed. I now believe residual oil migration past the rubber cap, after I bled the brakes following a fork replacement, fouled the pads.

Here is a list of the lubricants I use for bicycles and a few notes about each one.

General Grease
Park Tool PolyLube 1000 (PPL-1, Tube)
Use for general greasing. Threads of fasteners, coating bearings before installation, etc. This is a go-to grease that gets used on everything unless there’s a specific need for something special.

Chain Lube
ProGold ProLink Chain Lube
Use for all chain lubing purposes. As this lube is a heavier oil in a lighter carrier, I use the following process: Wipe chain with dry paper towel to remove dirt and old lube. Wipe chain with alcohol-soaked paper towel if it’s particularly dirty. Apply one drop to each roller on the inside of the chain. Turn crank backwards for 10-15 seconds to ensure lube is well distributed. Use a new dry paper towel to wipe off the outer plates of the chain (lube does nothing here). Let sit for a while, perhaps overnight, before riding so the the volatile compounds in the lube can evaporate leaving only the useful stuff. It’ll pick up less dirt this way, too.

Waterproof Grease
PEAK Synthetic Marine Grease (branded as Advance Auto Parts Marine Grease)
Used whenever a heavy, highly water resistant grease is needed. I use this on the lower bearing on headsets, bottom bracket spindles, car hitch racks. Use with caution as this grease attracts dirt, thickens, and migrates pretty easily and thus isn’t good for basic lubricating. (Any standard marine grease will work in place of this, the Advanced Auto Parts version was the cheapest when I bought some.)

Anti-Seize
Permatex Copper Anti-Seize Lubricant
Anti-seize is a grease with metal powder in it, used to inhibit galvanic corrosion when dissimilar metals are in contact. Instead of the original parts corroding the small metal flakes in the grease will corrode, prolonging the life of the parts and preventing seizing. I mostly use this on titanium frames as it’ll quickly corrode aluminum parts (such as headset cups, bottom brackets, seatposts, and mounting screws) but also use it on steel and aluminum frames when installing press-fit headsets and threaded bottom brackets, as a preventative measure.

Suspension Grease
Buzzy’s Slick Honey / Slickoleum / SRAM Butter
All three of these products are the same thing. It’s ideal for lubricating anything that slides or is suspension-related. Also works great on dropper posts. It’s also an ideal lube for Hope freehubs.

Small / Fine Parts
Tri-Flow Superior Lubricant (Drip Bottle)
This is a very thin lube which carries PTFE (Teflon). Perfect for lubricating small pivot points such as derailleurs and shifters.

DT Swiss Ratchets
DT Swiss Special Grease (Red, HXTXXX00NSG20S)
DT Swiss hubs, with star ratchets, specifically call for a tacky, yet somewhat thin, red grease which DT Swiss calls Special Grease. So little is used on each cleaning that a small container, one of which comes with every replacement ratchet set, will last for years.

Friction Paste
Finish Line Fiber Grip / Park Tool SuperGrip (SAC-2)
Sometimes things slip when you don’t want them to (eg: seatposts, bars) or you want to add extra grip without torquing tighter. Friction paste, a light grease with sandpaper-like grit in it, is perfect. It’s common to use this on the handlebar clamp part of a stem to ensure the bar doesn’t move, on seatposts in carbon frames, etc. Never use this on anything which is supposed to move, and be aware that it’ll abrade the clamped surfaces of whatever you apply it to.

Spoke Nipple Lube / PTFE Paste
ULTRA Tef-Gel
When building wheels I lube the spoke threads with ULTRA Tef-Gel, which is a PTFE (Teflon) paste. Designed for use on saltwater-exposed fasteners, this is an incredibly tenacious anti-corrosive that keeps spokes and nipples from binding together doubles as lubricant during assembly. Use ensures they’ll still be turnable after years of year-round exposure. This also works well for installing press-fit bottom brackets which call for PTFE paste.