Hollowtech bearings

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Ok, I did know I might have trouble with them right from the off but I wasn't expecting grunching at 200 miles. It was a ride along the beach which did it. It looks and feels like sand got past the seals, which I've read is the main problem with hollowtech, that the seals don't, well, seal. Is there a better aftermarket hollowtech or a seal you can fit which is better?

They are cheap and easy to replace but not cheap if I have to do it every 200 miles.
 
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Yellow Saddle

Yellow Saddle

Guru
Location
Loch side.
Hollowtech has many flaws, your problem is just one of them. I don't think sand got past the seals unless you perhaps pedaled underwater whilst sand was slushing around. The seal won't normally let sand past it. My guess is that you don't have mudguards and that the salty water sprayed up the back, dripped down inside the seatpost and then collected in the BB where the water slowly seeped into the bearings. My second guess is that you have no drainage hole in the BB shell of the frame.

Let me know if my crystal ball is malfunctioning or not.

Having said that, Hollowtech is a very poor design and a result of a legacy problem. If we can wipe the slate clean and redesign the bicycle we won't end up with hollowtech BB adapters at all.

One good thing about Hollowtech BBs is that the price came down quite a lot from the early days. Then it was worthwhile replacing the bearings but nowadays the entire adapter cup is cheaper than a quality bearing. Further, you can now buy them individually whereas previously it was the set or nothing.
 
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Yellow Saddle said:
Hollowtech has many flaws, your problem is just one of them. I don't think sand got past the seals unless you perhaps pedaled underwater whilst sand was slushing around. The seal won't normally let sand past it. My guess is that you don't have mudguards and that the salty water sprayed up the back, dripped down inside the seatpost and then collected in the BB where the water slowly seeped into the bearings. My second guess is that you have no drainage hole in the BB shell of the frame.

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Oooh I don't know how many points I can give you for that. I do have guards, I did cycle in sandy water, through the tide line actually and I'll have to check on the drainage hole. I took the cranks off and there was, naturally enough, sand everywhere. One bearing was refusing to move until I loosened it off and the other was OK, both feel stiffish now but I don't have a tool to remove the cups until next week and I haven't looked if I can pop the seal and get to the bearings anyhow?

Edit: but the rear guard is on the seatpost, so spray can still drip down.
 
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Yellow Saddle

Yellow Saddle

Guru
Location
Loch side.
Crackle said:
Oooh I don't know how many points I can give you for that. I do have guards, I did cycle in sandy water, through the tide line actually and I'll have to check on the drainage hole. I took the cranks off and there was, naturally enough, sand everywhere. One bearing was refusing to move until I loosened it off and the other was OK, both feel stiffish now but I don't have a tool to remove the cups until next week and I haven't looked if I can pop the seal and get to the bearings anyhow?
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OK, that's quite a confession. I think the bearing is innocent in this instance. But I'll give you 5 marks for at least trying with the mudguard. Tell me, was it at least fun peddling through the surf and sand? If you remove the cups next week only, the bearings would have rusted beyond saving. Further, it is impossible to get the plastic seal off without cracking it. Lastly, the bearing in there is a 6805 - however, not a real 6805. It is 4mm wide instead of 6805's 5mm. You cannot buy a replacement bearing at all from normal bearing companies. You can get them from enduroforkseals.com (search Enduro bearings bicycle if that link doesn't work).
 
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Oh and my original question still stands. I realize I've gone beyond normal operating conditions here but is there a better sealed Hollowtech than the Shimano cups, as it strikes me that any gritty water is going to get in and shorten the life considerably.
 
Cubist

Cubist

Still wavin'
Location
Ovver 'thill
Well, kind of better sealed (just) , but in any case more rebuildable. Gusset EX24. They have a removable tophat shaped bearing shield, However, given that you can generally get SLX/XT standard BBs for less than a tenner online if you shop around, there's a train of thought that wonders why you would bother. Gusset, apart from having a name that @Fnaar would get all sniffy about, also come in bling colours, don't cost the earth, and have the added advantage that you can remove the bearing seals with a pick, flush and regrease them. That's the problem with Shimano.. if you know you've got them wet you can't (easily) get into them to sort them out, although it isn't impossible, and you don't have to take them out of the frame to do it.

There;'s always Hope to consider. You can pick them up for about £30 used, and again, are rebuildable, but more importantly regreasable.
 
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Yellow Saddle said:
? If you remove the cups next week only, the bearings would have rusted beyond saving
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No, it was last Tuesday and I've done another ride since, during which the BB complained bitterly for a few miles but then freed up. So I think I may well have considerably shortened their life but they ain't dead yet.

Here's the offending ride:-
https://www.cyclechat.net/threads/your-ride-today.173254/post-3702485

Cubist said:
Well, kind of better sealed (just) , but in any case more rebuildable. Gusset EX24. They have a removable tophat shaped bearing shield, However, given that you can generally get SLX/XT standard BBs for less than a tenner online if you shop around, there's a train of thought that wonders why you would bother. Gusset, apart from having a name that @Fnaar would get all sniffy about, also come in bling colours, don't cost the earth, and have the added advantage that you can remove the bearing seals with a pick, flush and regrease them. That's the problem with Shimano.. if you know you've got them wet you can't (easily) get into them to sort them out, although it isn't impossible, and you don't have to take them out of the frame to do it.

There;'s always Hope to consider. You can pick them up for about £30 used, and again, are rebuildable, but more importantly regreasable.
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Flush your gusset, splendid: I'll look into them but you're right. Doing some reading around after I posted this leads me to wonder if it's worth it. I did read that adding some grease on the seal lip will help the waterproofness, that could be useful but I'm not desperate to add a couple of miles of beach to one of my rides so I may take my usual procastination route and do nothing followed by the easy option, replace. Or then again......
 
Venod

Venod

Eh up
Location
Yorkshire
I replaced Shimano & Race Face cups at an alarmingly fast rate until I got fed up and fitted Hope cups, been on the bike for about 2 years now with no problems.
 
Yellow Saddle

Yellow Saddle

Guru
Location
Loch side.
Crackle said:
No, it was last Tuesday and I've done another ride since, during which the BB complained bitterly for a few miles but then freed up. So I think I may well have considerably shortened their life but they ain't dead yet.

Here's the offending ride:-
https://www.cyclechat.net/threads/your-ride-today.173254/post-3702485
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Born to be wild, sounds gnarly but the BB clearly found it too offensive and wilted.

A note on my answer to your question about better seals. I said no. I could have added that you won't find better seals but you do find serviceable BBs such as those mentioned and Chris King. The nature of these seals is such that they cannot be waterproof but that's a long story for another day.

Where I lived there used to be a company that organized coastal tours and I had a few customers in my repair shop that participated in these tours. They would bring their bikes in afterwards and they'd be stripped to the last nut and bolt, all bearings replaced and frame washed out. It was good for business, so I don't want to discourage you from riding in the surf. It puts food on someone's table somewhere.
 
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Yellow Saddle said:
Where I lived there used to be a company that organized coastal tours and I had a few customers in my repair shop that participated in these tours. They would bring their bikes in afterwards and they'd be stripped to the last nut and bolt, all bearings replaced and frame washed out. It was good for business, so I don't want to discourage you from riding in the surf. It puts food on someone's table somewhere.
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Yes, well, now I've fully reflected on my seaside sojourn, I think I'll cross it off the list. Total ride time, 40 mins. Bike cleaning time, at least double that and I've still got a sandy chain which will need re-visiting. Fettle time for pedals and BB, another hour, shortened life of BB, all in all, I've changed my mind, it wasn't worth it and 35quid a day for a fatbike I just give back is sounding like a good deal.
 
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