Yeah, well, it's about 30 minutes away and I just haven't had time. Not going to make it there during a work week, and this weekend has been full of other errands and chores. That's one reason I almost always ride at night. And I've already ridden it over 1,000 miles this way, what's a bit more.

I'm not too worried about the LBS fixing it for free or not. Don't care. I wanted to see what was in there myself.

Been watching Park Tool videos to learn more about headsets. So please bear with me if I don't have all the terminology down.

Looks like the top bearing is an integrated design with a sealed cartridge bearing.



But when I pulled out the fork, at the bottom I found the caged bearing that seems to be a zero stack setup. Lots of dirt and crud, and no grease left.


Here is the cup that is press-fit inside the bottom of the head tube:


The reason for the gap appears to be the crown race. It was not press-fit onto the fork, I was able to slip it off with my fingers. It was just sitting on top of this shoulder on the fork.
Or is this shoulder on the fork the crown race, and for some reason they added another? I don't think so, but at the same time when I inspected the crown race that I slipped off I don't see how it could be driven over this shoulder.



Here is the bearing next to the crown race I removed. I cleaned them up, added grease, put it all back together the same way, and have the same gap. I don't really have a tool that I could have used to drive on the crown race, and if it's the wrong one, I didn't want to damage anything.


I'm going to try to make time to bring it back to the shop this week. Maybe Wednesday afternoon. I am wondering if they can drive out the bottom cup and convert this over to an integrated design with a cartridge bearing? I think it was supposed to be that way from the beginning. If not, I'll have them replace the rusty crown race and bottom bearing, and seat things properly.

Mark

First off, the bottom bearing looks to be upside down in the second photo and it also looks like that could have been a cartridge bearing that has come apart and the rusty cup in the bottom of the headtube may be the other piece of the cartridge. Check if it can be pulled out but don't force it as it may be a cup bonded to the headtube.

I think the bearing orientation is OK. I hand-fitted the bearing with the crown race back into the bottom of the headtube oriented the way it came out, and it fit nicely, with the crown race flush with the bottom of the headtube. I then tried flipping the bearing over and it would not fit.

I tried to pull out that rusty cup in the headtube and it would not budge. I think it needs some kind of puller. I don't believe it can even be driven out from above. It's like the bottom of the headtube was designed for an integrated cartridge bearing, but instead they drove a cup into the headtube for the caged bearing.

Mark

That appears to be the bottom half of a cartridge bearing that was reassembled upside down into the top half. Luckily it didn't do much damage to the frame or fork. The orientation you show in the last photo is the way that race and bearing retainer should have been in.

Just a stupid mechanic that didn't know what they were looking at. But you need a new lower cartridge and to get the top race of the old bearing back out.

^Bingo. Though I might replace “stupid” with “inexperienced/overconfident”.

Trek lists this lower bearing as “Trek E2 FSA 36 degree lower bearing”.

Personally I would try to find out from Trek if that cup is bonded into the frame and if so, removal would be a no no. It does appear to have a concave surface designed to be in direct contact with the bearing balls and not a drop in cartridge bearing which is why I suspect that it's part of a cartridge that's come apart and stuck to an integrated bearing headtube cup but I'm not certain, so you need to find out for sure before trying to remove the rusted cup. Your photos show that there are two orange seals (photo #2 and one of them is covered in rusty gunk) that look like seals from a cartridge bearing like the one seen in your photo of the top headset bearing. If you can determine that the rusty cup in the headtube can be removed, soak it in PB Blaser or similar to make it easier to remove without using heavy duty methods.

Can you please send me a link to where you found that information? I have been looking for a parts manual, but I must not be looking in the right place.

Great, thanks all. I can see now where it could be a cartridge bearing that came apart. That would also explain why the caged bearing is so soft. Not sure it is even steel, I can easily flex it between my fingers, which surprised me. But if it was meant to be inside a cartridge bearing, it would have had more support.

I'll provide an update once I get it to the LBS. Even if that rusty cup in the headtube can be removed, I'm worried that I could damage the carbon without the proper tool. I'm going to leave it to them. At least now I have some good photos to show them what they will find when they get it apart.

Mark

Are you referring to the ball retainer? That's plastic and just holds the balls apart.


Pretty sure you have a cartridge bearing that came apart and the top half rusted into the frame. A bearing puller at the bike shop will get it out.

That is from the dealer specs (I own a shop that sells Trek) for the 2024 FX 4, which it looks like you have based on the color. I don’t think Trek makes these specs available to retail customers for non-current models but any Trek dealer should be able to pull them up. I think what’s still in your head tube is one part of the bearing cartridge. The whole cartridge really should have been replaced when it was serviced, and I’d take it to the shop and ask them to sort it out.

Best course... Look up the Proper HeadSET for your bike... then take the bike to a reputable shop and have them order/install the COMPLETE HEADSET, AS A UNIT, not piecemeal...
and tell the owner of the shop that did that "10 balls replaced" work that one of their mechanics either needs trained more, or fired.

that WAS a sealed "cartridge bearing" before it failed and rusted into pieces.
that failed, RUSTY piece of scrap metal should have been replaced, in it's entirety.... and frankly, the ENTIRE headset should have been replaced, at that time.

Ah, thank you. No, mine is the 2021 version. Different geometry, and not gravel. Has 11-speed GRX and 32 mm road tires. https://www.trekbikes.com/us/en_US/b...ort-4/p/32262/

The shop where I bought it and where I have been getting it serviced was an independent in 2022, but now it is a Trek-owned shop. So hopefully they will get this straightened out.

Mark

Ah OK. Specs for that one just say “Aheadset 1 1/8””, which could indicate ball bearing retainers rather than a sealed cartridge. Either way I’d be taking it back to where it was serviced, as that gap should definitely not have been present.

fully integrated headset, fairly new CF frame... cartridge.

I agree a cartridge is much more likely, especially given the photos, but it really just needs trained eyes on it at this point to confirm.

a picture is worth a thousand words...
Ebayt Search: "6807-2RS ball bearings two side rubber seals bearing 6807-rs"

i've seen quite a few sealed "Cartridge" Bearings that have failed in my multiple decades as a mechanic... that's a failed sealed bearing, for certain.. you can see the lip that retains the seal.

the 6807 has no Bore chamfer, or OD chamfer, btw.... just a light clean up radius.

two for just over 7 bucks, shipped..... and up.

Thought I would close out this thread with the resolution.

Brought the bike to my shop late on Sunday afternoon. They were not busy, so the tech put it on a stand and disassembled the headset. I told him I had shown photos to some experienced mechanics, and the consensus was a cartridge bearing that had blown apart. He said maybe, but some Treks had a cartridge bearing at the top and a caged bearing at the bottom, plus during Covid they could have used anything handy if they were short on parts. I said OK, but either way can we replace what I had with a full cartridge headset?

If you go to the Trek website for my bike and click on the part number for a replacement headset, you get this Cane Creek: https://www.trekbikes.com/us/en_US/e...dset/p/427082/. They had one in stock so I decided to have them go ahead and replace my headset with this one.

It was ready by noon on Monday. When I went to pick up the bike, the tech apologized. He said it was an exploded cartridge bearing. He was thinking Trek FX3 with the caged lower bearing, not an FX4. Everything is now nice and tight and feels great. He had to add an extra 5mm spacer to keep my bars at the same height.

Total cost was $75, which I was fine with. I didn't get charged for any misdiagnosis when the bike was last serviced, the work they did was all part of the tuneup fee. So I'm out some of my own time and maybe a bit of labor on the headset swap, but I've also learned a lot. I'm happy.

Thanks again to everyone that offered their opinions and advice.

Mark

It should have been the cost of parts, minus the 18 ball bearings from last time, with no labor because this should have happened at the tune up. You needed a 5mm spacer because he sent you home with the headset jacked up and a gap underneath.

Where did the original spacer go? Was this bike ever assembled correctly?

BRAVO! Thats the proper engineering attitude. I am confident this will get resolved whether you take it to the shop or not. Most likely it will be better done if done yourself.
Its such a common complaint and finding that lately even when you pay good money to good people to do a job you can still get inferiour work. RATS! Its hard not to Micro-Manage.

OH, dont forget Marine Grease when you put it back together... Ha

Further more you posted some really good pictures for you post! Nice Bike!

It was close to the cost of parts. I think that headset is about $45 from Cane Creek, but Trek's price is $70. It is not worth the added stress to me to try to argue them down further for a few bucks. They were friendly and accommodating, and turned it around in less than a day.

It may not have been correctly assembled at the factory. I don't know. Definitely not done right at the service, but that was months ago. My bad for not catching it sooner. Plus I took it apart myself to see what was in there.

Didn't lose a spacer. The stack was the same as when the bike was new. But the headset cover of the Cane Creek is shorter than the Trek part, and they had to make up the difference.



Thanks again,

Mark