Tandem Tom

As I continue to learn my question is about the hubs on our tandem. There are DT540 Hub DT Swiss brand. The question I is are these sealed bearings? I cannot seem to find anything on there website.
Thanks!

WillFam-Reno

https://www.nzsbbearings.com/bearings/6000-bearing.htm
Shows a sealed OR shielded bearing 6000 bearing. I believe that my 540 is sealed.

Here is the manual so you can see the picture and 6000 bearing named in the parts list.

https://www.dtswiss.com/Components/Hubs-Road/540-tandem
Website that shows the 540 hub and components.

Hope that is of some help.

Tandem Tom

Thanks I missed that on the website

PMK

We had a 540 on our previous off-road hardtail. Our two current tandems also run DT hubs. The Co-Motion has TD's which are basically 540's except for the name / decal. Our off-road tandem Ventana runs a 135 mm DT 440rear hub. We also run DT fronts and have a spare set for the road tandem that need to be built into wheels. Great hub in my opinion. Basically the Detroit Locker Posi for cars of bicycle freehubs. Yes the bearings are sealed. Should be stainless too. There are four bearing, two in the hub and two in the freehub.

FWIW, you should accomplish some easy routine maintenance on these hubs. Not the bearing but rather the drive ratchets and springs. The drive can be removed by removing the right side axle end cap. It is retained by a tiny O ring. Then the entire freehub slides off. There are two springs, two ratchets and a spacer. These are cleaned and reassebled with a special Molykote grease. For the road and off-road tandems I have used the special grease but it does not last forever. Typically about 6 months for us. I now normally use Mobil 1 140 wt gear oil. It doesn't take much and also does not turn waxy over time.

The tech tip though is to remove the tiny O ring, this will allow a true no tools disassembly. Often with the O ring installed, you will need to use an axle clamp, drill chuck or other collet style tool to grab and pull the axle end from the axle. Once the O ring is removed, the QR will keep it from falling apart.

We have several sets of DT hubs, other than grease waxing up problems we have had very good luck with them. We did explode a Cannondale / Coda old style Hugi, but that was the Cannondale portion that failed. We did slip and round one set of drive rings on account of waxy grease, and we trashed the aluminum freehub body on our Ventana from the cassette digging in pretty bad. Bought a new freehub body in steel and all was well and being abused again.

FWIW, over the years, there have been random posts here about broken rear axles. We do have a spare axle in the spares box we take to events or anytime we travel to ride. The axle is not expensive and is easy to replace. It may be worth buying a spare for that just in case. With care the axle can be tapped out, obviously protecting the surfaces with a block or plastic. The axle comes out to the left (after freehub removal), this removes the left side bearing. A new axle can be slipped in and the bearing seated. Not a common problem but worth knowing about.

Have fun and enjoy.

PK

justcrankn

There's no maintenance for the bearings, but I service the star ratchets every year. Remove the skewer and leave the cassette lockring on. Now the cassette can be pulled straight out. Then the ratchets can be cleaned and relubed.