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If you look on the Shimano crank arms the version type should be printed onto it on the inside next to the pedal hole.

I went and had a look in my garage at a new boxed Shimano Deore XT M8100 crank and it doesn't come with those spacers. The Shimano bottom bracket doesn't come with those spacers either.

There are a few different versions of the Shimano Deore XT crank arms with different q factors. The M8100 being the narrower version 172mm q factor, 52mm chainline and M8120 being the wider version 178mm q factor, 55mm chainline. The M8100 doesn't have spacers but I'm wondering if the M8120 might have a longer axle and then spacers added on each side to achieve that 6mm wider q factor? That could explain why your crank has spacers on perhaps if it's the wider M8120 version.


I don't have an M8120 crank on hand to check for sure. :(
You are right. The M8120 has those spacers. One on each arm.

 

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Yes that’s it! The Shimano manual is also slightly changed when you search for those specific crank! They added 1 page with info about the spacers.

Thanks for helping!
 

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Following on from the above... The XTR M9120s have a spacer on the left side only. The m9120s share the left crank arm with the m9100s, but have a different right side arm that has the 'spacer' built in.
 

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Thanks for posting the spacer crank information. It's the sort of thing that's always handy to be able to refer to in future.:)

Regarding bottom brackets I've been meaning to post some updates about how the parts on my Orbea Oiz have fared over the last year.

I've got a Wheels Manufacturing BB86/92 Thread together bottom bracket and it's been completely trouble free.


The rear suspension pivot bearings may be wrecked after a year of riding but the bottom bracket bearings still feel good and smooth. :)
 

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Cane Creek 70 and 110 has a good bottom seal.
That’s a good spot. It looks like there’s an additional rubber o-ring seal on the crown race that sits on the fork crown with a Cane Creek 110 headset.

The stock Acros crown race that I’m using currently doesn’t have an o-ring seal there.

Have you got one of the Cane Creek 110 headsets on your Orbea Occam? I think I’m going to change that part on my bike if it fits.:)
 

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No, though my Occam hasn't seen any nasty yet. I might just put a 110 on the occam now that I know the Acros has a similar problem, really don't want to do any damage to the frame.

I've used CC40's and always had crud get past the seal and onto the bottom bearing. Then I got the 70 and apparently it has similar or the same bottom seal as the 110, and works much better at...sealing. I have the 70 on my commuter bike and it sees alot of crap including salt.

The crankset discussion is interesting. The occam came with an 8100 and I'm going to take it off to put on a bigger chainring going from 32-34 (34 round is the max). But I was thinking if I had the 8120 it might just move the chainring out enough to run a 36.
 

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I haven't got my Orbea Oiz frame or fork here at the moment (it's still at the bike shop waiting for the warranty suspension parts to turn up.) 🤕

To illustrate what the default headset sealing looks like these pictures show the lower bearing and fork crown race of my 2012 Specialized Epic. It has the same layout as an Orbea Oiz. The lower cartridge bearing sits on the fork crown race and when the headset is pulled tight the bearing slots into the moulded carbon fibre hole in the bottom of the frame head tube.

The cartridge bearing has a rubber seal covering the bearing but there is no seal between the frame and fork crown race so there is a small gap there allowing dirt and water to get inside to the bearing.

With this particular headset and fork in the bike has only been ridden outside a few times as it is usually a dedicated turbo trainer bike. Even so, there's a bit of dirt visible in the headset around the bearing in these pictures.

2012 Specialized Epic Headset 2.jpg


2012 Specialized Epic Headset 1.jpg
 

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I haven't got my Orbea Oiz frame or fork here at the moment (it's still at the bike shop waiting for the warranty suspension parts to turn up.)

To illustrate what the default headset sealing looks like these pictures show the lower bearing and fork crown race of my 2012 Specialized Epic. It has the same layout as an Orbea Oiz. The lower cartridge bearing sits on the fork crown race and when the headset is pulled tight the bearing slots into the moulded carbon fibre hole in the bottom of the frame head tube.

The cartridge bearing has a rubber seal covering the bearing but there is no seal between the frame and fork crown race so there is a small gap there allowing dirt and water to get inside to the bearing.

With this particular headset and fork in the bike has only been ridden outside a few times as it is usually a dedicated turbo trainer bike. Even so, there's a bit of dirt visible in the headset around the bearing in these pictures.

View attachment 1912717

View attachment 1912716
That sure does look like rust.
As that’s mainly a trainer bike is that from sweat dripping down through the headtube?
 

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That sure does look like rust.
As that’s mainly a trainer bike is that from sweat dripping down through the headtube?
The picture is a bit misleading because it had the flash on to show the inside of the head tube. What you can see is that red grease mixed with dirt on the outside of the bearing, rather than rust.

This picture shows a Cane Creek 110 headset. That blue rubber seal on the lower crown race is what's missing from the headset in the pictures above. I think it might be worth having if it will fit the Orbea Oiz. That blue rubber seal will fill the gap between the fork and frame to help keep water and dirt away from the lower headset bearing in a way that the stock headset doesn't. :)

Cane Creek 110 Headset Lower Seal.jpg
 

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I took the bike fully apart today to look at the state of the bearings and swingarm threads. I've attached some additional photos showing the fully disassembled drive side bearing and threads of my 2020 Orbea Oiz.


View attachment 1910195



The rear view picture shows that when the main pivot bolt is fully tightened the drive side bearing sits on the threads of the pivot bolt, rather than on the solid metal part of the pivot bolt. There is no spacer on that side. With the bolt installed all the wear on the anodising is at the bottom of the bolt.

View attachment 1910194

The drive side bearing is gritty but not completely seized with the swingarm removed. The non drive side bearing is also a bit gritty but in better condition than the drive side bearing. When assembled with the swingarm in place and the worn pivot bolt it looks like there is a lot of slop exerting uneven pressure on the bearing however. When riding it would most likely be seizing up fully as the swingarm twisted to the side.

View attachment 1910197

The threads into the swingarm aren't great but aren't completely stripped as once cleaned out the bolt would thread back in. The threads are worst at the bottom of the swingarm where it has been sitting at an angle instead of square with the drive side bearing. It looks like the swingarm has been rubbing on the frame/ edge of the bearing.
I too have a similar issue as yours but mine still makes me in doubt if the frame didn't crack too.

My main pivot bolt on the drive side bearing bed clearly got "destroyed".

My doubt is... To you, does the frame look ok on that side? Because to me I'm in doubt it that is only cosmetic or not.

Pictures attached
 

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I too have a similar issue as yours but mine still makes me in doubt if the frame didn't crack too.

My main pivot bolt on the drive side bearing bed clearly got "destroyed".

My doubt is... To you, does the frame look ok on that side? Because to me I'm in doubt it that is only cosmetic or not.

Pictures attached
My bike is still at the bike shop at the moment. I'll take some pictures of my frame's bearings to compare with the next time I'm there. :)

In your bolt picture it's clear that one or more pivot bearings had seized. There is that silver wear mark where the anodising on the alloy bolt has been worn off as the suspension moved but the bearing didn't rotate. There is visible friction wear around that drive side bearing too.

Edited picture rotated to match my ones in post below.

nhgmr1 Orbea Oiz Driveside Bearing.jpg




In the drive side frame pictures there is a carbon fibre tube bonded into the frame that the pivot bearings press into. Based purely on the photos if you follow the green dots round it is still uniform all the way round the outside of the tube bonding. The tube connection to the frame looks like it is intact.

In the same picture if you look at the pressfit pivot bearing seat where the bearing is pressed into the carbon fibre tube I've marked what could possibly be damage to that area with the red dots. When you ride a bike with seized bearings it can put a lot of force onto those bearing seats. Instead of its ball bearings rotating the entire seized pivot bearing will try and rotate inside the carbon fibre tube that it is pressed into. It can ovalise the bearing seat so the bearing is no longer tight in the frame.

There appears to be some uneven gaps between the edge of the bearing and carbon fibre tube in the direction of pedalling force . It needs a really thorough clean, to get all the dirt out of those edges, so you can inspect what is underneath to see if it's just cosmetic or if the bearing has come loose.

If a set of replacement bearings can be pressed into the carbon fibre tube bearing seat, and they go in firmly, then I suspect it could still be ok.
 

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I took the bike fully apart today to look at the state of the bearings and swingarm threads. I've attached some additional photos showing the fully disassembled drive side bearing and threads of my 2020 Orbea Oiz.


View attachment 1910195



The rear view picture shows that when the main pivot bolt is fully tightened the drive side bearing sits on the threads of the pivot bolt, rather than on the solid metal part of the pivot bolt. There is no spacer on that side. With the bolt installed all the wear on the anodising is at the bottom of the bolt.

View attachment 1910194

The drive side bearing is gritty but not completely seized with the swingarm removed. The non drive side bearing is also a bit gritty but in better condition than the drive side bearing. When assembled with the swingarm in place and the worn pivot bolt it looks like there is a lot of slop exerting uneven pressure on the bearing however. When riding it would most likely be seizing up fully as the swingarm twisted to the side.

View attachment 1910197

The threads into the swingarm aren't great but aren't completely stripped as once cleaned out the bolt would thread back in. The threads are worst at the bottom of the swingarm where it has been sitting at an angle instead of square with the drive side bearing. It looks like the swingarm has been rubbing on the frame/ edge of the bearing.
Please keep us posted on what conclusion your LBS and/or Orbea come up with.

Really interested to learn if this was a design or component flaw and what the solution is.

Thanks!
 

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Here are some pictures of the drive side and non drive side rear suspension pivot bearings on my bike. Both drive and non drive side pivot bearings are seized and don't rotate.

I wrote that post yesterday and then my pictures are far grimier. It's some mixture of rust, grease and bits of ball bearing that's thoroughly stuck on.😂

The drive side bearing on my bike has a little marking in the same place as the red dots on the picture of nghmr1's bearing above but it is quite minor. The non drive side bearing side looks fine. It's evenly fitted all the way round the bearing.



2020 Orbea Oiz Driveside Bearing.jpg


2020 Orbea Oiz nonDriveside Bearing.jpg
 

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I had some rust visible just above the drive-side bearing and given what you guys showed here I was curious about what's going on on my Oiz. Took it apart, it was quite dirty. The bearing aren't running smooth, but not too bad either.

1913878


Here is a picture of the bolt. I guess the width of the wear marks show that the drive side bearing rests partially on the threads. :oops: The bolt is supposed to be tightened to 25 Nm. I didn't even go to 25 Nm and it was sticking out on the drive side. WTF?!?! See the bottom half of the picture, where I put on the chainguide to illustrate by the gap how far the bolt sticks out. If tightened to 25 Nm it would probably stick out 3 millimeters or so. And no, I did not forget the non-drive side washer.

1913880
 

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Guys, found this while cleaning my workshop floor under the bike stand. I have no idea where it belongs, could be from the Oiz, could be unrelated. Any ideas? It looks like it is meant to secure a bolt or something similar, so I am slightly concerned.

1914002
 

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Yes, it is safety washer from brake pads guide pin and it's probably from your Oiz.
You can put it back if you want. But they usually break after multiple use.
 

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I had some rust visible just above the drive-side bearing and given what you guys showed here I was curious about what's going on on my Oiz. Took it apart, it was quite dirty. The bearing aren't running smooth, but not too bad either.

Here is a picture of the bolt. I guess the width of the wear marks show that the drive side bearing rests partially on the threads. :oops: The bolt is supposed to be tightened to 25 Nm. I didn't even go to 25 Nm and it was sticking out on the drive side. WTF?!?! See the bottom half of the picture, where I put on the chainguide to illustrate by the gap how far the bolt sticks out. If tightened to 25 Nm it would probably stick out 3 millimeters or so. And no, I did not forget the non-drive side washer.
Something I realised was that although my bike's main rear suspension pivot bearings moved and initially rotated roughly when I first took the bike apart they might have been freed up by the process of removing the main pivot bolt. The next day after sitting overnight they were seized and after a month hanging up in the bike shop are stuck solid. Thinking back there was a definite "pop" the very first pedal stroke at the beginning of the ride from the rear suspension for a few weeks previous to the pivot bolt coming out, as though the bearings were sticking and that first suspension compression was breaking them loose.

Did you take the orange bearing seals off and repack the bearings with grease whilst you had it apart?

I've attached a zoomed in picture of the drive side bearing on your bike. The pressfit seat where the bearing goes into the frame looks fine as that's nicely round all the way (the green dots). :)

What I thought was interesting in your frame drive side bearing picture is that there's lots of corrosion visible internally. The sleeve inboard of the bearing has a lot of rust on and there are what appears to be water droplets in there too from the reflections. It looks like the bearing has been sat in water and rusted from the inside. The other two bikes drive side bearing pictures have much less corrosion on the inside and clean-ish looking sleeves. It might never have dried out fully since that hypothetical lake submersion months ago!

Daniel Thomas Orbea Oiz Driveside Bearing.jpg


Here's a Orbea Oiz Pivot Bolt wear comparison picture.

2020 Orbea Oiz Pivot Bolt 3 Comparison.jpg


The top bolt is from my bike, the middle bolt is yours and the lower bolt is nhgmr1's.

They aren't quite to equal scale but the red lines show roughly where each bike has had the bearings making contact. For drive side bearing support your bike looks to have the most contact with maybe 2mm of round pivot bolt under the bearing whilst mine is worst with about 1mm of round pivot bolt (there's a slight step visible if you look closely which would originally have been round axle until it was ground away.)

The amount of black anodising that has been worn away gives a rough indication of whether the bearing is moving smoothly or not. An all black finish would suggest that the bearing has been rotating whilst missing anodising could be down to the bearing not turning and the pivot bolt wearing away.

My pivot bolt at the top is in a real state on the drive side whilst the non drive side doesn't look too bad.

Your pivot bolt looks questionable on both sides. That non drive side in particular is showing enough wear on the anodising that it could be binding.

nhgmr1's pivot bolt at the bottom of the picture looks really bad on the drive side as all the anodising is missing in a clear band round the round section of the pivot bolt (the seized bearing has worn it away) but the non drive side is unmarked. The shiny threads all the way along this bolt are a bad sign too. The other two bolts have black anodised threads so the shiny threads suggest the whole bolt has been moving.
 

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What I thought was interesting in your frame drive side bearing picture is that there's lots of corrosion visible internally. The sleeve inboard of the bearing has a lot of rust on and there are what appears to be water droplets in there too from the reflections. It looks like the bearing has been sat in water and rusted from the inside. The other two bikes drive side bearing pictures have much less corrosion on the inside and clean-ish looking sleeves. It might never have dried out fully since that hypothetical lake submersion months ago!
I feel very ashamed about it. :oops:

Thank you for making the comparison! It's positive that all bolts have the same number of threads. :ROFLMAO: Your's must have been loosened quite a bit to wear where it did. The drive side wear patterns on the other two bolts look wrong to me because they are thinner than the bearing. Do you have a spacer between the bearing the chainstay on the drive side? I only had one on the non-drive side. When I saw that the bolt sticks out when tightened my first thought was that there is a drive side spacer missing, but there is none in the blue paper. Looking at the wear location, I think the spacer should be moved from the non-drive side to the drive side to have the bearing face not rest partially on the threads. Not sure if that will work though. If I remember correctly, the inner face of the chainstay is not the same on both sides.
 
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