Dura Ace Pedal bearing service/replacement

Discuss light weight issues concerning road bikes & parts.
Post Reply
petromyzon
Posts: 258
Joined: Mon Apr 05, 2010 4:14 pm

by petromyzon

I made the mistake of opening one of my pd7810s because I was concerned it had got water in the bearings. It hadn't, but I had obviously dislodged something because now it will not close. It gets to within about half a mm on the threads compared to how it used to be adjusted, but not all the way. Correct number of bearings installed (17, 9 and the roller bearing) and it hasn't got too much grease in there whilst I figure out what is wrong. How should the bearing retainer on the larger race sit?

Anyone else serviced one of these or can point me towards a how to? The Park one just says don't do it!

petromyzon
Posts: 258
Joined: Mon Apr 05, 2010 4:14 pm

by petromyzon

See photo below:
http://db.tt/LU9AgwOX


LH pedal is correctly adjusted, RH is not. The first gap between the spindle and the axle cone assembly is too small on the RH pedal, meaning that the axle cone assembly cannot close up snugly to the pedal body. The exploded view
http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/PD/EV-PD-7810-2662_v1_m56577569830612675.pdf" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

does not shed any light on how I have managed to move the cone on the spindle, but it certainly didn't require a lot of force! Any help greatly appreciated.

by Weenie


sanrensho
Posts: 409
Joined: Tue Aug 02, 2011 5:54 pm

by sanrensho

Coincidentally, I've been working on overhauling a set of PD-7810 pedals for the last two days.

I posted about it here:

http://forums.roadbikereview.com/compon ... 89166.html" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

My issue is play in the spindle (assembly). I think my problem may be related to the rubber sleeve (wear?) that sits between the spindle and cone piece, but I have yet to find a way to eliminate the play.

For your issue, can you not simply back off on the locknut? There should be a gap there.

boots2000
Posts: 1407
Joined: Mon Oct 15, 2007 9:28 pm

by boots2000

Sorry to hear is. In my experience, opening a Shimano pedal is the kiss of death. Once opened- they will die in 6 months.
Shimano pedals usually last forever- but when you get a bad one it is all over.

petromyzon
Posts: 258
Joined: Mon Apr 05, 2010 4:14 pm

by petromyzon

Thanks guys! Yes, wish I had never touched them. The good side has been perfect from the day I bought them and is buttery smooth after thousands of wet kms. The bad side developed a tiny bit of play but I should never have touched it.

Sanrensho, how do you access the rubber sleeve/get the cone bit off the spindle? Take the circlip off? Yes I can tighten the locknut closer to the pedal body but not far enough, the cone assembly seems to be in the wrong place on the spindle by about a mm and I'm not sure how it got there. The first gap after the pedal thread stopper was about 1.5 mm and is now about half a mom.

daj
Posts: 246
Joined: Mon Oct 12, 2009 6:36 pm

by daj

See the exploded view chart for the components: http://techdocs.shimano.com/media/techd ... 612675.pdf

The rubber seal should be 'underneath' the ball bearings, on the pedal thread side. Use something small and pointy between the bearings to push the seal down if they interfere with the bearings. If the seal sits correctly, the bearings should fall in to place and should be touching each other (there should not be any gap!) when you push the lock nut towards the circlip. If they do not fall into place while assembling, push the locknut up so the bearings sit in the right place while assembling.

petromyzon
Posts: 258
Joined: Mon Apr 05, 2010 4:14 pm

by petromyzon

^^ daj, top man, thank you. I don't think the seal is seating properly as the bearings are not sitting together, I will try to push it back gently and then rebuild with fresh balls.

sanrensho
Posts: 409
Joined: Tue Aug 02, 2011 5:54 pm

by sanrensho

daj wrote:The rubber seal should be 'underneath' the ball bearings, on the pedal thread side. Use something small and pointy between the bearings to push the seal down if they interfere with the bearings. If the seal sits correctly, the bearings should fall in to place and should be touching each other (there should not be any gap!) when you push the lock nut towards the circlip. If they do not fall into place while assembling, push the locknut up so the bearings sit in the right place while assembling.


Thanks for this, daj. It sounds like the rubber seal needs to be sitting a certain way when the axle assembly is finally inserted into the body, but I'm having a hard time picturing this.

Do I need to position the rubber seal in the direction of the bearings, so that the seal and sliding part (cone) eliminate any play between the cone, bearings, and circlip? So it's a positioning/play adjustment that needs to be done right before reinserting the axle assembly into the body?

Thanks!

User avatar
Tinea Pedis
Posts: 8416
Joined: Sat Mar 14, 2009 6:08 am
Location: Geelong
Contact:

by Tinea Pedis

So my left hand DA 9000 pedal seems to be 'leaking' grease

Image

only just noticed it. Which given my bike is washed every couple of rides, can only be within the last day or so.

Spinning the pedal it also feels 'rough'. Thoughts?

eric
Posts: 2196
Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
Contact:

by eric

If it feels rough it needs a rebuild. Probably including a new seal.

User avatar
Rick
Posts: 2001
Joined: Sat Aug 29, 2009 4:30 pm

by Rick

boots2000 wrote:Sorry to hear is. In my experience, opening a Shimano pedal is the kiss of death. Once opened- they will die in 6 months.

I guess I will be testing that theory.
I have a 7900 set that was still very smooth, but was in fact so frictionless that the pedals wobbled around wildly and made it difficult to clip in.
I had just come off experimenting with the Look Keo Blade 2, which doesn't rotate at all when unclipped, which was actually easier for me to clip into because they stayed in the position you last unclipped.

So I removed the spindle assembly from the 7900 set (just as shown in the Park Tools webpage instruction) and jammed the bearings full of a heavy marine grease without removing the bearings from the spindle assembly. I then pretty easily adjusted the bearing preload so that they are smooth, with no play or noticeable bearing drag.
It seemed successful; it "quieted down" the rotation of the pedals, but they are still low friction and smooth, just a lot more viscous. It was really quite simple with 20mm and 17mm cone wrenches. We'll see how long they last now, and I will report back.

TheDarkInstall
Posts: 723
Joined: Sun Jan 26, 2014 3:44 am

by TheDarkInstall

Thread resurrection...

@Rick;

1. Did the pedals remain smooth after you serviced them?

2. When you took them apart, did you by any chance get a look down into the pedal body, and check out the loose ball and needle bearing assembly? If so, how was it positioned? Were the loose balls sitting right at the end of the pedal body cavity, with the needle bearing sitting further in, around the middle of the axle?

Would love to be able to find a cutaway diagram / photo of an assembled Dura Ace pedal.

eric
Posts: 2196
Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
Contact:

by eric

There's diagrams in DM-PD0002-07-ENG.pdf (the dealer manual) in the techdocs link above.

The balls and needles at the end of the axle have always stayed in place for me. Doesn't mean they will for you of course.
I have taken three or four apart and they're all still working well.

by Weenie


User avatar
Rick
Posts: 2001
Joined: Sat Aug 29, 2009 4:30 pm

by Rick

TheDarkInstall wrote:Thread resurrection...
@Rick;
1. Did the pedals remain smooth after you serviced them?

Yes. No problems at all. I am still using them and they are very smooth. In fact, I have not regreased or anything since that original posting, and I was shocked to look back and see how old it is!. The heavy marine grease did exactly what I had hoped and the pedals still feel a lot more viscous than stock, but the bearings are still smooth.
2. When you took them apart, did you by any chance get a look down into the pedal body, and check out the loose ball and needle bearing assembly? If so, how was it positioned? Were the loose balls sitting right at the end of the pedal body cavity, with the needle bearing sitting further in, around the middle of the axle?

Well, I don't remember specifically, except that I think I MUST have looked down into the body because I tried to get it really "packed tight" with grease. It was oozing grease pretty good as I was screwing the cover back into the body. I didn't see any "loose" bearing in there. Maybe it was just held in place by the original grease. :noidea:

Post Reply
  • Similar Topics
    Replies
    Views
    Last post