Originally Posted by
Lasse
I don't count my own positive experiences with tools as representative for the general quality of a product, but according to many bikeshop guys, who also happen to cycle around the world from time to time, (on the wereldfietser.nl forums, including people who build and sell touring frames/bikes for a living) say external BBs often last only about 10000km, square taper ones often last 50000km. Not my mini experience, but their expert experience. Most of the time they advise LX hubs and a BB-un54 in combination with Sugino XD cranks. Deore dérailleurs will get you around the world too. When you're not racing, there's no point in paying lots of money to get the latest ultra light race tech although it can of course feel very nice to be riding with extra bling
I just checked some recent Shimano techdocs and apparantly there are XTR rear hub models with smaller bearings (3/16") and other models with bearings the same size as LX (1/4"), so this is making a general comparison LX vs XTR more difficult... Same with XT apparently. (higher model numbers, smaller bearings)
Using mountainbiking as a test isn't appropriate for touring bikes imo, the use is very different. Distances on an MTB are much shorter, touring bikes are constantly heavily loaded while MTBs get more short hard shocks and cleaning/maintenance of an MTB is usually much more frequent. Replacing parts on a mountainbike when they're worn out is also less crucial at home than when you're touring through Mongolia or the amazon rainforest.
I can confirm that I was advocating the LX hub over the XT or XTR as being more suitable for touring and can just about differentiate a sprocket from a hub. This is just as well as for a number of years I worked as a mech for a Bike Charity and still run courses in Bike mechanics for them.
I've toured for almost forty years and always with heavy camping loads. Every year I clocked up in excess of three thousand miles in July and August cycle-camping in France so do feel qualified to express an opinion. XT was always the hub of choice for touring for many years but the new design with smaller ball-bearings has met with many reports of breakages in this country. LX is now advocated as a replacement given that it has retained the larger ball-bearings and kept its rep as being very durable.
I agree that outboard bearings have a shorter life than their square-taper counterparts. I've changed many of these with too few miles on them though I suspect that this may be partly due to the BB shell not being faced before the bearings were fitted as well as the increased vulnerability to muck and spray given their position. Whatever the reason I confess that I still prefer the more robust square-taper when push comes to shove.