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15

A lot depends on the rider and what you mean by efficiency. It is easy to keep a hub gear running well for years, but an unmaintained derailleur will become inefficient very quickly. A hub gear allows the chain to be fully enclosed, for all but the most dedicated cyclist; an enclosed chain will be more efficient as it will be cleaner and better oiled. An ...


12

Jan Heine performed some wind tunnel tests of "Real World Aerodynamics" a few years ago. A link to a blog post (and the results published in Bicycle Quarterly) can be found here. Those tests cover only one component (the aero drag component) of commuter-type bicycles vs. "racing" bikes. If you want to make your own apples-to-apples comparisons of ...


11

I don't have an internal hub, but I want one for the following reasons: They are sealed and protected from the elements. They are nice for commuting because you can shift them while stopped... If you've ever stopped at a red light on a normal bike and struggled to get going again because of your gear, you can appreciate this. With an Internal hub, you can ...


11

It depends on the model you get, but the efficiency is generally comparable. Derailleurs that are in really good condition and properly lubed will be more efficient, but marginally, and will often be less efficient due to real world conditions. At least that's what the wiki says: http://en.wikipedia.org/wiki/Hub_gear I have one road bike with a 3x9 ...


9

Replacing a hub is not a "simple" procedure -- it, at a minimum, involves relacing the rear wheel, probably with different sized spokes (whose size you must accurately determine). Relacing is not beyond the abilities of a competent backyard mechanic, but is a skill that needs to be learned. To add a second chainring you must install some sort of device to ...


8

I bought a 700c Jericho hardtail in 1997, which came with a Rohloff 14 speed internally geared hub. I used it as a commuter for five years, at least 150 miles per week, 50 weeks of the year. That's 37500 miles. Even assuming I took a week or 2 out in there for whatever reason, call it 35000 miles. After that, I continued to ride it one or 2 days a week, for ...


8

The lack of popularity is partially because it's a solution in need of a problem. The effect of rotating mass in general is generally overstated when considering the total energy that goes into cycling, and mass near the axle has even less of an effect. You can work out the math here. The main advantage comes when considering unsprung mass on ...


7

It depends on the style of master link and how much chain tension is in your setup. An SRAM power link needs about 1-2mm of chain slack to unhook the link. If you can find this amount of slack, it should work with most types of master link. If your chain doesn't have 2mm of play, but isn't too tight, a master link that snaps off the side (like the first ...


7

In 2001, Kyle and Berto published a comparison of the mechanical efficiency of several configurations of derailleur and internally-geared hubs in Human Power, which you can find here. Among the systems tested were a Shimano MTB derailleur system, a Sturmey-Archer 3-speed hub, the Shimano 7-speed Nexus hub, and the 14-speed Rohloff hub. MTB derailleur systems ...


7

In the 5 years have you had the hub rebuilt / repacked with grease? The maintenance schedule for the Nexus 8 speed is every 5000 km or 2 years, which ever comes first (I believe). If you have not had any maintenance in your 5 years this is likely the culprit for decreased performance. 20,000 km should be no problem for a properly maintained hub; however, ...


7

Typically you quote gear sizes in gear inches, very basically this is the drive wheel diameter multiplied by the ratio between the two gear cogs, traditionally quoted in inches. Also sometimes mentioned is development which is the amount of distance travelled by one revolution of the cranks (the astute will notice that is going to be proportional to gear ...


5

Daniel summed up the first half of your question pretty well. For the second half, start by visiting this link to learn how to adjust the hub. When you go to inspect the bike try what you've learned first. If the shift lever is obviously sticky it may just need new cable and housing. Other than that, it's hard to tell. Internally geared hubs typically aren't ...


5

I have a Rohloff and have sent some emails to the factory due to severe oil spill (had to replace the seals, successfully). From what they have told me, the 25ml of oil is more than double the necessary amount for the hub to work fine, since the oil is very sticky and it distributes inside the hub. Even the unavoidable oil "sweating" should be considered ...


5

If she liked the Lime, why not look at the second hand market. Get one and have it serviced by a good bike shop and off she goes... Edit : Quick 1 minute search and I found This - why go second hand.....


5

I see a few different sizes of chain, broken down as follows 1/8 inch wide chain Single Speed / Internal Hub only, don't use with a standard derailleur. Can fit on 1/8 inch or 3/32 inch chainrings and cassettes. It will have some play when installed with a 3/32 chainring or cassette, but it's usable. So, if you accidentally buy an 1/8 in chain and have ...


5

No, it is not a good idea. You'd be spending more than the bike is worth even for a basic internal gear hub (even assuming you got the wheel rebuilt for free using the existing rim and spokes, if possible), let alone buying a rear wheel with an IGH built in. You do need a chain tensioning pulley or horizontal dropouts, which while can be built more robustly ...


4

Well, about a year ago, I got A shimano Alfine 11 Speed . . . thing didn't even last 700 miles!!!!! (Several of the gears don't even engage . . . at first, thought the chain broke.) And Shimano doesn't even service it. Also have a Rohloff, with nearly 19,000 miles, no problems so far. 'Nough said!


4

The 8i uses what Shimano calls a cassette joint. It's wraps the cable around the back side of the hub and as the shifter pulls the cable it moves a bracket counterclockwise backwards on the hub body. Cable tension on a brand new Nexus/Alfine 8-speed hub needs to be precise. Do this: Shift the bike into 4th gear Find the cable tension indicator. There is ...


4

There are a couple of crank designs that use this principle. Off hand, the HammerSchmidt crank from SRAM is the most practical current application of it because it doesn't require deviation from the current frame specifications. While it is only 2 gears, and the shifting is built into the crank, rather than inside the BB shell, that is a limitation of ...


4

No, with either the 8 or 11 speed Alfine hub, there is no possibility of using it on a 120mm frame. The hub shell itself is about 120mm wide, without the cable carriers for shifting, or any spacers at all. If, as it appears from your 120mm reference, you are considering a fixed gear frame with that spacing, then you should reconsider. 120mm spaced dropouts ...


4

Based on the number of other people asking the same question around the internet, I suspect the answer is no. This page contains the best wrap up I've found of available shifter options for Rohloff hubs. Mittlemeyer may be bringing out some brifters that work with hydraulic brakes in September, but they've already delayed their earlier March release date.


4

I can only compare the basic Shimano Acera and Deore (3x8) deraileurs to the Rohloff 14-speed hub, but these are my observations. On the Rohloff hub Rohloff, like most hub gears is slightly less efficient than a well-maintained derailleur, as this PDF study explains. In my experience the difference is not noticeable, perhaps because I've mostly used cheap ...


4

The other answer is a pretty good list of differences, so I'm going to try to complement it with a fluffier, more hands-on answer that I think better describes the experience of riding with hub gears. I switched from derailleur to a Shimano 8-speed hub two years ago. My daily commute was 8 km each way back then, in all weathers. The short answer is that you ...


4

You are correct. This is different than "regular" cables. On regular cables you pick the end you want and cut off the other. Thats because the connection on the cut-off end is usually a clamp. You run the cable under a screw/nut and tighten it down. Then you just put a cable crimp on the end to protect the cut cable However, your internal hub cable is ...


3

Pretty much as above. They are generally dependable, maintenance free, and easy to use. Also heavy, difficult-to-impossible to service, and sometimes a bear to get loose if you have a flat tire. I fixed a flat on a Nexus hub wheel a couple of years ago, and getting the thing back in place and getting the cable properly lined up and tensioned ...


3

I've not set up the Alfine 11 specifically, but it's quite similar to it's less-geared cousin. You might also consider the Alfine 8 - it's rather cheaper and is a well-regarded hub with only slightly less total gear range. In either case, the main things you'll need will be the hub (the SG-700-L is for disc and rim brakes), a 26"/559 rim of your choice, ...


3

It sounds as if you adjusted the barrel adjuster out too far, the last time you adjusted it, and damaged the threads on the adjuster. When the shop cleans and lubes it, it is fine for a few days, and then gets stuck again, because the threads are cross threaded or stripped. If the damage is relatively minor, it can act normal until it is under a little ...


3

The first thing you should be looking into is gearing to ensure that an internally geared hub will work for you! The more you pay, the more gear range you get out of a hub, but even the nicest internally geared hubs don't match the spread of standard mountain bike gearing. If you've decided that an Alfine 11 hub is for you then to answer your questions in ...


3

SRAM acquired Sachs in 2000. The main visible difference between the (Fichtel &) Sachs Torpedo 3 hub and the SRAM T3 is that the SRAM T3 comes in an aluminium body, whereas the Sachs Torpedo 3 comes in a chrome plated steel body and the brake design has been changed (but is compatible). There appearantly was a successor model to the Sachs Torpedo 3 ...



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