Originally Posted by interested
Doesn't have one myself, since I dislike riding bicycles with internal gears, this hub is however fairly common where I live, so I do have some knowledge about it. (I assume you don't mean Shimanos new so called "Ultegra level" hub.)
An obvious authority.
Originally Posted by interested
The verdict pretty much is, that this hub is OK for very light, low speed commuting, but are really bad for even moderate distance, all weather commuting (rain and frost).
A colleague of mine has a 25 mile round-trip commute. His 8 speed Shimano Nexus Rollerbrake broke 3 times within the first year, requiring a major overhaul each time, before it finally disintegrated two weeks ago. His new LBS (who sold him a new wheel) told him that he had to bring the hub in every 1400-1800 miles for preventive maintenance or it too would be destroyed.
One could probably do the overhaul oneself (inspection, grease repacking, perhaps changing bearings). But since people usually buy these hubs because the don't want to do maintenance work, they probably won't.
Anyway, if one does all-weather medium distance one one of these hubs, they should expect them to be much more maintenance intensive than a normal dérailleur.
People on the danish bicycle forums I hang out in, tells similar stories. The hub isn't watertight, meaning that road grit and salt and water penetrates it, destroying the bearings. One guy even claimed that the entire hub locked up when cold because of water inside it.
Out of the 20 or so threads I've read regarding internal hubs, this is one of maybe 2 or 3 posts declaring that internal hubs have chronic upkeep issues. Most post I've read are somewhere along the lines of "Yeah, I just put some lube in it every 5 years or so and I'm good." My personal experience has been that internal hubs are almost maintenance free.
Originally Posted by interested
Another common problem is cable problems; since the hub has a weak internal spring (compared to dérailleur), the cable has a tendency to stick when freezing. Especially going from thaw to frost causes problems. Road grit or cable rust also hampers its cable action more than normal dérailleurs.
Never had this problem, so I can't comment towards it.
Originally Posted by interested
You can't use a QR with these hubs, so you need to ride with a wrench if you want to change the tube. The Rollerbrake version is really, really nasty regarding this, since all the bolts, nuts and cable adjustments, turns a simple tube-changing job into a laborious affair. (besides its breaking power doesn't impress me at all)
http://www.veratomic.com/
Yes, the rollerbrake sucks, don't get that version.
Originally Posted by interested
People also claim that the gear ratios aren't that good if you like to go fast (the SRAM 7 speed should be better in this regard). But I guess this is also a matter of personal taste.
Get a smaller cog.
Originally Posted by interested
Besides that, these hubs are heavy. I am not a weight weenie, but a rear wheel with such a hub, really feels like a bag of bricks to hold. The drag may be low, but for me it just sucks the joy out of cycling. This of course is a matter of personal taste, thousands of people use Nexus 8 speed hub and are very happy about it. The same with grip-shift; some like it, others don't.
Yep, the hub definately does weigh more than a cassette/hub. The thing is, if you're in the commuting forum, you probably want a bike that can maintain momentum. More weight on a wheel means a higher moment of inertia which means that the bike will coast much better than if it had a lighter wheel. The downside of course is that it will take more work to accelerate. Regardless, the difference isn't that great between cassette and internal acceleration/momentum.
Originally Posted by interested
The hubs are expensive. I don't know US prices, but where I live, a Nexus 8 speed rear wheel alone, usually cost the same as a pair of super strong Campagnolo Vento wheels + cassette, or a pair of Shimano wheels + cassette. Even a hand built rear wheel with Mavic rim and Shimano Ultegra hub are cheaper.
Let's see. $230 for the hub and shifter on Harris. And we all know how reasonable his prices are. [/sarcasm] Add a Shimano brake only lever for $50. You seem to think that The Nexus-8 isn't truly Ultegra level, so let's compare it to a 105 setup. $150 on nashbar for one shifter (assuming you want a single chainring up front for fairness' sake), $30 on nashbar for a 105 cassette (that you'll have to replace, compared to $10 for a new cog w/ the hub), ~$50 for a 105 hub, and $70 for a rear derailler. Internal $280, Cassette $300. Oh, enjoy the premium paid for your dished wheel too.
Originally Posted by interested
Normal dérailleurs are very simple, extremely durable and very low maintenance (if you don't mind that they look dirty), even though they look complicated with all their springs and moving parts. They are cheap too compared to internal gears.
Not as low maintenance as internal hubs. I do mind the dirt; it's a commuter and w/ internal I get to use a chain gaurd. As regarding affordability, see above.
Originally Posted by interested
In fact I personally can't find any significant point where these expensive (though not high quality) hubs with internal gearing are better than normal dérailleurs and hubs. Their perceived low maintenance probably is much worse than normal gears, they have drag, they are heavy, they are expensive, they make the wheel difficult to service, you are restricted to grip-shift (IMHO), can't run very fast because of gear ratios, may need more cable maintenance than normal etc.
All personal opinion w/ nothing to back it up.