With the thousands of pedal strokes taken by a recreational cyclist, it’s easy to forget that the pedals themselves, as tough as they are, need a bit of tender loving care now and then. Give them a twirl. They should spin easily at first, but eventually slow down and stop due to the buttery grease inside. If they either keep on spinning, or worse, are reluctant to spin, they need some attention.
TOOLS NEEDED
- Tools for removing pedal from crank arm. This is either a 15 mm pedal wrench, or some sort of hex key. Shimano pedals with no wrench flats typically need 6 or 8 mm hex keys.
- Shimano’s TL-PD40 pedal tool is required for removing the spindle assembly from cheaper pedals like the PD-M530. This plastic tool mates with splines on the pedal spindle.
- The TL-PD40 is best used with a bench vise. Alternatively, locking pliers such as Irwin Vise-Grips also work.
- Grease.
- Wrenches in 7 and 10 mm.
- Paper towels or rags for cleaning up.
Start by removing the pedal off the crank arm. I strongly suggest shifting to the big chainring first before doing this, to protect your hands and arms against the painful bite of chainring teeth. Also, work on one pedal at a time, so that you don’t get confused with the different screw threading of the left and right pedals.
Once the pedal is off, we want to remove the spindle assembly. For these PD-M530 pedals, we will need to take the TL-PD40 tool and mate it with the splines on the pedal spindle. More expensive pedals, such as my Deore XT PD-T780s or my Saint PD-MX80s, need only an adjustable wrench to separate spindle from pedal body. The pedal body itself will have directional arrows telling you which way to turn the tool to loosen and remove the spindle.
The spindle itself may be too tight to loosen by hand, so a bench vise or locking pliers will help greatly. An adjustable wrench can also help, provided it’s big enough to fit the wrench flats of the TL-PD40.
Here we can see the pedal spindle assembly, which I’m told is basically shared by all Shimano pedals. The shiny cylinder on the inside is where all the action happens, as it’s got the cups for two sets of loose ball bearings. At the end is a bearing cone nut and a lock nut, which together set the bearing preload for the entire assembly.
BEARING PRELOAD ADJUSTMENT
If you feel grinding and gritty resistance as you spin the pedals, this is the time to adjust. (Otherwise, feel free to move to the next section.) Take your 10 mm wrench to hold the cone nut, then break the lock nut loose with the 7 mm wrench.
The idea is to back out the cone nut, and to retighten it just enough so that the bearings can still spin freely, but with no side-to-side play or slop. You’ll have to play it by feel, as bearing preload adjustment with cones is mainly trial and error. Shimano actually makes it pretty easy by not requiring the cone to be tightened down all that much, though.
Once you’ve got the bearing preload set, you want to tighten the cone against the lock nut as much as you can with your 7 and 10 mm open wrenches, so that your preload adjustment holds and is effectively “saved”. Not tightening the lock nut enough lets the cone walk out of your desired adjustment and become too tight against the bearings again, bringing back the gritty action. I had to repeat this twice on my left pedal.
REPACKING AND REASSEMBLY
The beauty behind Shimano pedals is that servicing them is pretty easy. It involves nothing more than squirting a good dollop of fresh grease into the empty pedal body, then reinstalling the pedal spindle.
You want to be very careful inserting and screwing the pedal spindle into the pedal body, though. You’re working with very fine screw threads, and your pedal spindle’s got them cut into not-so-strong plastic, so avoid cross-threading, take your time, and make sure the spindle goes into the pedal body straight. I managed to strip some of my left pedal’s threads as I was working in a hurry; at least only the threads for the first two rotations were damaged and I could still get away with using the pedal.
Tighten the spindle into the pedal body as far and as snug as it will go with the TL-PD40 – no more. The excess grease should ooze out of the pedal spindle, so wipe this off.
Once reassembled, turn the pedal spindle to check the bearing preload by feel. It should spin smoothly. Ideally, you shouldn’t have to adjust anything, but this generally is your last chance to check for mistakes.
All that’s left to do is to grease up the pedal spindle threads before reinstalling pedal to crank arm, and it’s job done. It’s worth doing this job at least once a year, as it’s easy enough to do and will greatly improve the service life of your Shimano pedals.
the accidental randonneur 