Cheetah

Hi,

It will be nice if long time tandem riders could let us know the average durability of the different components of a tandem drivetrain. I know it may be dependant of the team weight, the kind of road (hilly or flat) but it would be nice to have an idea of how many miles a certain component should survive. Of course I am talking about component that are well maintained, cleaned and lubricated as per the manufacturer recommendation.
This may actually look like a survey!!

Here we go.

Sealed wheel bearing
Timing chain
Final drive chain
Timing chainring
Final drive chainring
Cassette
Bottom brackets
Headset

merlinextraligh

in my experience, casssettes, drive chain, derailleurs, wheel bearings, have less than half the life expectancy of same components on a single bike.

I haven't noticed, bb's, or headsets wearing out any faster than a single bike.

In 14 years on our Burley, never replaced a timing ring, and IIRC only one timing chain.

justcrankn

Sealed wheel bearing - more than 12000 miles
Timing chain - 3000 miles riding in slop w/o fenders
- 6000 miles otherwise
Final drive chain - 5000 miles
Timing chainring - 3000 miles riding in slop w/o fenders
- more than 9000 miles otherwise
Final drive chainring - 8000 miles
Cassette - 5000 miles
Bottom brackets - more than 12000 miles
Headset - more than 12000 miles
I have never had to service or replace a sealed wheel bearing, bottom bracket, or a headset on any bike.

johnlyons53

On our Santana a couple of the drivetrain parts all decided to pack it in at about 3000-3500 miles - the stoker's BB bearing and the EDCO rear hub. I'm now running Shimano hubs and Dyads with 48 spokes. Also when I replaced the rear chain and all of the chainwheels (re-geared with smaller sizes) I started to skip on the two smallest cassette sprockets so that needed replacing also. Everything else is fine so far.

TandemGeek

Sealed wheel bearing - Service per manufacturer's recommendation
Timing chain - Service life of aprox 1.5x your single bike's drive chain
Final drive chain - Service life of aprox. 0.5x - 0.75x your single bike's drive chain
Timing chainring - Varies by size / material / how often you change your timing chain. What ever it is, it can be at doubled by 'flipping' the rings front to back once the driving teeth have become elongated. Using odd-numbered teeth or a 1/2 link will also extend the service life of timing rings.
Final drive chainring - Service life of aprox. 0.5x - 0.75x your single bike's drive chain
Cassette- Service life of aprox. 0.5x - 0.75x your single bike's drive chain
Bottom brackets - Varies by type. Assume 1.5x for front and 0.5x for rear as an average. Better quality NOS square tapers like Shimano UN72 may last 25k miles, whereas some of the newer wide axle Octalinks may last less than 4k miles. Better ISIS seem to hold up pretty well,
Headset - Service per manufacturer's recommendation. Before sealed bearing headsets, tandems that were ridden hard would eat headsets.

MB1

Sealed wheel bearing-It is going to vary by brand, miles, rider weight and road conditions. Let's just agree that it is going to be a good long time.

Timing chain. Why mess around? Change it every time you change the drive chain. Or not, IME the things are going to outlast the drive train by about a factor of three.

Final drive chain. Again the riding conditions, team weight and riding style will make a bigger difference than anything else. The more often you lube, clean and replace it the less often you will have to replace the much more expensive chainrings and cassettes.

Timing chainring. They are going to last a long, long time.

Final drive chainring. Keep 'em clean, don't let your chain get too worn and 10s of thousands of miles are possible. Again, riding style, rider weight and riding conditions are the biggest variable here (after maintenance).

Cassette. Likely you can extend the life here by replacing just the worn cogs (if the cassette allows it). The usual variables apply.

Bottom brackets. Are they sealed bearing? If so they will have pretty good life although the rear ought to wear out much faster than the front.

Headset. Sealed bearing-keep it clean and adjusted and it can be a lifetime component. Ball bearing? A few thousand miles of hard riding will be all the excuse you will need to change over to a better sealed bearing unit.

Of course there are exceptions to everything but if you just take care of your stuff it will take care of you.

Cheetah

Thank you all for your informations. I always take great care of my bikes. Cleaning and lubricating chain is part of my routine maintenance. Chains wear is something that is measurable with a gage. It is a bit more difficult with bearings. For our trip, I am going to replace the chains and I will buy some spare wheel bearings and a spare BB in case they let go during the trip.

Have a nice day,
Michel