CDU 4: Internally Geared Hubs

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1. Can this be used with a recumbent trike or bike?
2. How much does the Rohloff hub weigh?
3. Too much power lose no thanks.
   
   
4. I see this in my future (at least the IGH). I'm getting tired of cleaning and replacing chains/cassettes. Give me this with a FULL chainguard and I'm happy.
5. campy is awesome im not going to spend over 100$ on a peice of plastic that sounds like a kid chewing on a rubber band
6. this is cool and i would love to switch but as far as i know you need a special frame for that, to insert and remove the belt
7. Has somebody make a dual belt system to duplicate the number of gears? ...2 front rings mated to two rear sprockets.
8. I Would like that system on my dual drive bike....pedal with your hands as well as your feet. Why would you want to do that? It's a total aerobic workout and adds 4-5 miles per hour to your cruising speeds.
9. New transmission CVT design by BitRaptor. Is a continuously variable transmission CVT gear only (the only one functional in the world), very compact and lightweight, and which could replace the current systems both for efficiency, simplicity and not least the costs. Because this CVT work only with pinions is better the all other systems by efficiency and high torque transmission. In the web page bitraptor com you will find more explanations, drawings and a short video of a basic prototype. 
10. Cantilever brakes. They have incredible stopping power, but need frequent adjusting and it's not like the old days where you just turned a screw, you have to move the pad closer to the rim on each side and if they aren't equidistant, I think it can cause dishing or bearing problems. I definitely don't want coaster brakes, but lever based drum brakes seem to be the best option for bad weather. In fact, I am thinking of replacing my front wheel for a drum brake model (70% braking in the front).
11. You'll have to research all the brands (Shimano, SRAM, etc.) and models (e.g. Alfine, Nexus, i-Motion, etc.) – there's a lot of choice, though the Nexus 8 seems to be manufacturer's preference these days. Some have coaster brakes, others "roller brakes" (Shimano's proprietary drum brake), others disc brakes, etc. I can't tell you more specifics as I've never looked into the braking options myself (my bike has the typical dual-pivot sidepull rim brakes you see these days).
12. They aren't that great in the rain. I constantly ride the brakes for a few seconds (very lightly) to keep them dry. The Salmon Koolstops are supposed to be good in the rain, but I don't have them. They also tend to squek in the rain.
13. Yes, it was a Sturmey Archer 8 speed. The reviewer took it apart and showed how it worked and he mentioned that first gear was a 1:1 ratio. I'll check out the Nexus and Rohloff. Do they come with optional lever operated drum brakes? I fucking hate the cantilever brakes I have(though they are VERY good in dry conditions when properly adjusted). You have to make sure they are equidistant from the rim (to avoid rim dishing) and make contact below the lip of the rim (which causes them to get stuck)
14. Oh cool, if you scroll down the page I linked to at the end of my previous post, Sheldon specifically explains hybrid gearing. He says you could use a rear derailer as your chain tensioner if you wanted.
15. That was probably a Sturmey Archer 8-speed or similar, the first gear in that is direct drive (1:1), meaning it goes from 1:1 to 3.24:1. Since an SA 8 can only gear up from the cog, it requires a very small chainring to make sense. A much more typical IGH would be the Nexus 8-speed, which goes from 0.527:1 to 1.615:1 as I said. When coupled with a normal chainring/cog, this gives a pretty standard range. A Rohloff can do 0.279:1 to 1.467:1! That's very wide. sheldonbrown com/internal-gears.html
16. I guess this must be my mistake. I thought I remembered a review of a IGH that went from 1:1 to some other higher ratio, which when mated to a 3:1 chainring/sprocket would make the lowest gear 3:1. I guess I misread it. Sorry. Can you direct me to a better review and explanation? I'd appreciate it.
17. That's why you use a chain tensioner, not a rear derailer. Functionally similar, so I see where you're coming from. Also, what are you talking about re: cannot achieve 1:1? Yes, the chainring:sprocket ration is large:small, but the whole point of the IGH in the first place is then you have internal ratios ranging from (say, on a Nexus 8) 0.527:1 through 1.615:1. A good IGH has a similar range of ratios to a derailer (a Rohloff is even wider).
18. To take up the slack of the chain. For example my chainring set is 48-38-28 You need something to take up the slack between the amount of chain needed between 48 and 38 and 38 and 28. A front derailleur has no ability to take up slack. One problem with an internal hub is you cannot achieve a 1:1 because the front chainring is always bigger than the rear sprocket on a IGH. My cassette has a 28 tooth cog, so I can achieve 1:1 - 1:4 (48/12). A fixed position derailleur wouldn't be such a headache.
19. Why would you need the rear dérailleur at all? You only need the front dérailleur in your hypothetical setup. The angled chain efficiency loss is very minor. My point is the moment you add a derailer, you're negating many of the advantages of an IGH without gaining much beyond gear range. It's not impossible, some few people do it, but most people prefer either all derailers (lighter, less expensive, high range, efficient) or all IGH (weathersealed, shifting when stopped, less maintenance).
20. I find that derailleurs are finicky, especially across an 8 cog cassette. With a rear derailleur in a fixed position under a single cog, I would think it would give you all the advantages of 3 sets of 8 speeds without the finicky rear derailleur (especially in the middle gears). How much inefficiency is caused by the chain not going perfectly straight (say in the worst case of the inner most chain ring on the front and the outermost on the rear say 8th gear on a 24 speed bike)?