problematic Shimano pedal

[lechatnoir]

I've got a set of 8yo 105 road pedals. They've been flawless as you'd expect, but recently, I noticed one wasn't rotating with gravity into the 'ready' position. It felt rough on the crank, while still spinning easy enough; just not with gravity

So, I rebuilt it, ensuring plenty of grease and that the spindle was smooth before and after inserting into the pedal body. There were no major warning signs i could see on the spindle. After a ride or two, it was spinning nicely again. Until now... it's rough again.

I'll rebuild it again, but is this the end?

[michaelbiker]

Just now, lechatnoir said:

I've got a set of 8yo 105 road pedals. They've been flawless as you'd expect, but recently, I noticed one wasn't rotating with gravity into the 'ready' position. It felt rough on the crank, while still spinning easy enough; just not with gravity

So, I rebuilt it, ensuring plenty of grease and that the spindle was smooth before and after inserting into the pedal body. There were no major warning signs i could see on the spindle. After a ride or two, it was spinning nicely again. Until now... it's rough again.

I'll rebuild it again, but is this the end?

It sounds like you either need to replace the spindle or the ball bearings. Check if you can see any pitting on the bearings or grooves on the spindle. I have a pair of XTR pedals that need new spindles but they are like hen's teeth.

[droo]

Did you completely disassemble the bearings, or just pull out, set preload, fill body with grease and purge as you tightened the collar back in?

Did you tighten the preload jam nut enough?

If you completely stripped it, then some of the balls may have come adrift. Those things are a pig to reassemble properly.

[lechatnoir]

41 minutes ago, droo said:

Did you completely disassemble the bearings, or just pull out, set preload, fill body with grease and purge as you tightened the collar back in?

Did you tighten the preload jam nut enough?

If you completely stripped it, then some of the balls may have come adrift. Those things are a pig to reassemble properly.

Quite right about the rebuild being tricky. The balls are tiny and stick to the most lightly greased surface. But I'm confident I got them all. None of the races were pitted either

When I took out the pedal assembly earlier, there was loads of grease still, but the jam nut was loose. I put an 8mm Allen wrench in a vice, mounted the spindle on that, then used the adjustment nut to set the smoothness/play, then carefully used the jam nut to lock it all down. Again... This time with a bit more tightness... quite a lot more really... This is only IDT, so worst case won't be too bad. Actually, worst case is a new set of pedals and I'd like to avoid that

[droo]

Ok, I'd guess jam nut not tight enough then. They do tend to tighten as you pedal rather than loosen, for obvious reasons...

Next time skip the complete disassembly part. Pull the axle assembly out, wipe all the grease off, set the bearing, half fill the pedal body with grease and reassemble. Old grease will be forced out of the pedal past the axle seal and you're good to go once you've cleaned it up and reseated the seal. It's a 10 minute job.