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Crankbrothers Stamp 7 Bearing Replacement

I got a refresh kit for my pedals and just serviced them — no more play! Here’s the pedal before service.

A Crankbrothers Stamp 7 right pedal with pedal washer. Lots of grease and dirt

Out comes two plate screws that secure the bearing retainer to the pedal body. Here’s the initial guts when you pull out the whole assembly. The small screw on the left is just from the grease port.

The spindle assembly of a pedal

The service manual has you use a paperclip to remove the outer bearing and o-ring. I couldn’t find one so I used a small hex wrench to knock out the outer bearing through the grease port and a J-bend spoke to grab the o-ring. (Aside: J-bend spokes have also been my heroine during many internal routing projects.)

The outer bearing and o-ring of a pedal

Then the inner bearing o-ring comes out, letting you pry off the inner bearing halves. Then you can slide off the seal. Here it all is!

The inner bearing halves and seal disassembled

Arranging all the new stuff from the refresh kit. Only the pedal body, spindle, bearing retainer, and pedal washer are original. Everything gets a light cleaning. The brand new igus bearings are shockingly slippery — pretty rad!

All the pedal components arranged roughly in the right order

The outer bearing looks strange — just a weird self-lubricating polymer!

Millions of the solid lubricants are embedded in tiny chambers in the solid, usually fibre-reinforced material. From these chambers, the material releases infinitesimal amounts of solid lubricants during movement. This is sufficient to satisfactorily lubricate the immediate surrounding area.

(I can’t believe I’m quoting marketing material but it’s so cool. Maybe it’s all bullshit, who knows.)

Dark grey plain igus bearing

The inner bearing halves have small lips which seat into the bearing retainer. Then the inner bearing o-ring goes over the whole assembly and the outer bearing is placed on top of the spindle. Here it is ready to get greased up and inserted into the pedal (remembering the final o-ring).

An entire spindle assembly with inner and outer bearings

Everything screwed back into the pedal body!

A Stamp 7 pedal facing towards the pedal threads with a cleaned up bearing retainer

And back in its home. Feels like new again! Strava puts this bike at 1840.3 km so we’ll see how many km I get out of these new bearings.

Serviced pedal installed back in the crank of an e-bike

Update: I went to do the same on the left pedal and the never-before-used Philips bolt on the grease port is seized. I find that once a bolt is seized you can’t use enough torque to free it before stripping a Philips head. Awful things. Follow-up post when I get it out with a bolt extractor.

Update 2: I just checked on Feb 25, 2024 and they have more play than ever! That didn’t last long. Debating whether to ride these until it’s a problem (and keep filling with grease in the meantime) or to try something new.