|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
best internal shifting hub?
RE/
Does this Rohloff, or the other new internal-gear hubs available these days, have the same design issue that Jobst has refered to existing in the Sturmey-Archer hubs that pitched him off the bike? Dunno what the Jobst issue was - but I've been riding Rohloff on my ATB for a few thousand miles and haven't run into anything I'd call an issue. Also, how loud are these things? I am getting spoiled by my quiet shimano one-speed freewheel! Depends on your sensitivity/perceptiveness and, probably, neurosis level. I consider mine TB very loud in gears 7 and below and fairly loud in gears 8-14. It's not just when pedaling either - lotta clicking going on in there with the pawls. I think it's something you have to hear and evaluate yourself. Personally, I don't care for the noise, but just bought my second Rohloff hub (for my hardtail) and wouldn't go back if I could avoid it. ----------------------- PeteCresswell |
Ads |
#12
|
|||
|
|||
best internal shifting hub?
What about the durability of the Rohloff hub? I always heard about how
great Phil Wood hubs are. I was very disappointed with them and repeatedly trashed the insides (esp. where the pawls bite into). You would think with all the gears inside the Rohloff that something is likely to go in a relatively short period of time. I weigh over 200 pounds too. You can imagine that I'm seeing myself spend $800 and then thrash the gears and its junk on the side of the road. Then I'm opening the hub up trying to figure out where 100 gears fit in there. So you're saying that there is more friction? Is that when coasting? only when applying force to the cog? I think the shifter on drop bars is not ready for prime time. If only someone could come up with a decent shifter for drop bars. I like the concept though. If these kinds of hubs are very reliable, then they sound great. Are we saying that if we take a road bike with say Ultegra trip and STI and switch to Rohloff and no derailleurs that its going to be roughly 2 pounds heavier? I'm just trying to get a ballpark figure. I wish Shimano was more flexible with the road group components. As it is STI is not cyclocross friendly in terms of brakes. On 28 Jul 2003 15:58:22 -0700, (Chalo) wrote: Khoomei wrote: What is the best internal shifting hub on these important points: - reasonably lightweight compared to a road group - reliable operation - parts are available from the usual channels, not some guy working out of his garage. - has more than 3 speeds. It seems like all gearhubs from 4 to 14 speeds weigh about the same 1.7 kg, give or take. With some you get a brake, making those effectively a little lighter. Only the Rohloff Speedhub gives step sizes between gears that compare to a road group. However, Sachs's and Shimano's 7 speed hubs give overall ranges similar to that of a road bike. (Road bike with 53/39 crank and 12-23 block: 260% Sachs/SRAM 7 speed: 303% Shimano Nexus 7-speed: 244%) If you need lots of gearing range and you can afford the Rohloff, then that's the one for you. I have had two, and I don't think anyone would find reason to switch back once accustomed to the Rohloff. If the price of the Rohloff is too much committment and/or you would like a drum brake, I recommend the Sachs/SRAM Spectro 7 speed. It is the most free-running gearhub (with more than 3 speeds) I have used, it seems quite durable, and the brake works consistently with minimal fade. Chalo Colina |
#13
|
|||
|
|||
best internal shifting hub?
You
would think with all the gears inside the Rohloff that something is likely to go in a relatively short period of time. I weigh over 200 pounds too. You can imagine that I'm seeing myself spend $800 and then thrash the gears and its junk on the side of the road. Then I'm opening the hub up trying to figure out where 100 gears fit in there. No experience with the Rohloff, but myself and many other Bike Friday owners have had good experience with the Sachs 3 X 7 (and 8 and 9...) hubs on Tandem Twos'days. Tandems make 200 pound loads look like nothing. Chris Neary "Science, freedom, beauty, adventu what more could you ask of life? Bicycling combined all the elements I loved" - Adapted from a quotation by Charles Lindbergh |
#14
|
|||
|
|||
best internal shifting hub?
Compared to a road group, they are all about 2 pounds (1 kg) heavier.
They all are more reliable than a derailleur. Parts availability should be good for all of them, although repairs will more likely involve the factory rather than some guy in a garage. Going on 4,000 trouble-free miles on my Nexus-7, whose' one disadvantage is a narrower overall gear range than on a typical derailleur bike. Paul |
#15
|
|||
|
|||
best internal shifting hub?
In message , Jennifer
Donleavy writes Does this Rohloff, or the other new internal-gear hubs available these days, have the same design issue that Jobst has refered to existing in the Sturmey-Archer hubs that pitched him off the bike? No. Not the specific problem he has described in this group anyway. He has written up a problem where an Sturmey Archer AW hub jumps out of high gear under heavy load when the rider is standing. The pedals give way and the rider falls. I do not know how common this behaviour is and how many thousands of miles service his hub had done before it failed. The detailed reason he gives for this failure only applies to a hub with a cruciform clutch passing load to the planet cage through extensions of the planet pins. This design was used in AW and the AG dynohub and the very similar drum brake 3 speed hubs. It was not used for medium or close ratios 3 speeds (such as AM and AC), or the 4 speed FM, FC or the FW and its five speed children the S5, S5/1 or S5/2. The 5 Star (early 1990s?) axle would probably break anyway with the sort of heavy use he describes so best avoid that one. The Sturmey Archer Sprinter 5s and 7s use a different form of clutch and an extra ratchet that means there is no neutral position. I've not seen inside the new 3 speed from Taiwan but understand that they use this system too. My first 5 speed Sprinter was made near the end of Nottingham production in 2000 and had a problem with heavy loads in first gear. It was replaced by the shop and its replacement has taken some hard use without any problems, bearing in mind that it's still nearly new in hub gear terms. I have read that the 7 speed Sprinter was not always reliable. I don't find I want to stand on the pedals in high gear on a 3 speed bike anyway. I'm happy to change down when I get to a hill, that is after all why we have gears, although I often stand to climb moderate and short hills in middle gear (direct drive on all 3 and 5 speed SA gears sold in the last 80 years or so I think). It's quite hilly round here so I prefer a 5 speed. Looking beyond the specific design problem attributed to the AW, any gear system could fail to carry load if it is overloaded or worn out. With totally exposed gears wear is more obvious (as well as very much faster) but I expect some riders have fallen off because they didn't notice that the teeth on their chainwheel had all but gone. Though not Jobst Brandt one would imagine. Rohloff specify a maximum torque but I've no idea about noise or longevity on those. Also, how loud are these things? I am getting spoiled by my quiet shimano one-speed freewheel! I can't help with a decibels figure but unless you plan to fit a gun mount and stalk game or poachers by bicycle you'll not be seriously disadvantaged. A little bit of noise is no bad thing. (Last Sunday on a quite country lane a dog walker stepped out in front of us on our nearly silent 24 speed tandem. Our combined panic yell made her jump back just far enough, just in time.) I doubt that you will hear any of the hubs in motor traffic or with planes or helicopters (our local Royal Navy noise makers) near. For some of us who had a hub gear in our now distant childhood that lovely nostalgic tick, tick, tick, in the middle gears is a great comfort.... On a more practical note the ticking in middle gear of a 3 speed or gears 3 and 4 of a 5 speed gives an instant health check on the low gear pawl springs. (Total failure here can also allow the hub to freewheel forward but in low gear in this case.) For older oil lubricated hubs, the tick also gives guidance on the lubrication status. See http://www.sheldonbrown.com/sturmey-...ml#lubrication Martyn Martyn Aldis, e-mail ================================================== ============================ |
#16
|
|||
|
|||
best internal shifting hub?
Chris Neary wrote:
No experience with the Rohloff, but myself and many other Bike Friday owners have had good experience with the Sachs 3 X 7 (and 8 and 9...) hubs on Tandem Twos'days. Tandems make 200 pound loads look like nothing. But small wheels significantly reduce a hub's torque load compared to full-sized ones. Chalo Colina |
#17
|
|||
|
|||
best internal shifting hub?
RE/
Frankly I'd be a little surprised if the difference were a whole two pounds or 900g, but it's in the ballpark. It's got to depend on the weight of what it's replacing. The one I put on my FS replaced a SRAM 9.0 setup. I weighed the whole bike before and after and the diff was almost precisely 2 pounds. ----------------------- PeteCresswell |
#18
|
|||
|
|||
best internal shifting hub?
I'm obviously in no position to quarrel with Pete Cresswell's scale,
but I wonder whether some of the weight pick-up he measured is attributable to the torsion bar that one generally has to use when converting existing bikes? The torsion bar is not needed if you are building a new bike with Rohloff dropouts. My Rohloff bike is a bit heavier, I imagine, than a derailleur bike with a triple chainring (which one also needs to factor in, to be fair), but I would have guessed that the number was a little lower than reported by Pete. But since my bike was built for the Rohloff, I'm not able to offer a precise before and after comparison. As to the Speedhub's efficiency, there are some newish articles on that topic in English at the Rohloff Germany site. (www.rohloff.de) My own anecdotal conclusions, which now have been tested by riding the same route on conventional and Speedhub-equipped bikes, are (i) I'm pretty slow on any bike, (ii) the Speedhub seems equally efficient when compared to a derailleur system in the top seven gears, and a bit less efficient in the bottom seven, and (iii) the actual efficiency differences are very minor. I'm coming to the view that many of us (including me) are thrown off by the aural clues of the Speedhub, so that when we hear those little gears whirring in some of the low gears, we subconsciously interpret that as vast quantities of energy being wasted. Unfortunately, I've found that switching to my derailleur bike doesn't get me in fact to the top of the hill all that much faster. Finally, as to reliability, I do remember Rohloff boasting a year or two ago that they never had the inner guts of a Speedhub fail in service, but I don't know whether they can still make that claim. The only issues that I have encountered, or remember reading about on the web, are (i) the possibility of oil leaks, which in fact are said not to be catastrophic at all (although a thirsty hub does run more noisily), and (ii) the possibility of the snap-apart connectors that enable you to disengage the shift cable, so you can remove the rear wheel, failing, which turns your 14 speed into a 1 speed, until you replace the cable. Hope this helps. Ed Kleinbard "(Pete Cresswell)" wrote in message . .. RE/ Frankly I'd be a little surprised if the difference were a whole two pounds or 900g, but it's in the ballpark. It's got to depend on the weight of what it's replacing. The one I put on my FS replaced a SRAM 9.0 setup. I weighed the whole bike before and after and the diff was almost precisely 2 pounds. ----------------------- PeteCresswell |
#19
|
|||
|
|||
best internal shifting hub?
|
#20
|
|||
|
|||
best internal shifting hub?
RE/
...wonder whether some of the weight pick-up he measured is attributable to the torsion bar... The bar, axle plate, and fittings to secure it to the stay weigh in at 125 grams. I used the SpeedBone instead...considerably less. So I think I'd stick with the 2 pounds. I'm coming to the view that many of us (including me) are thrown off by the aural clues of the Speedhub, so that when we hear those little gears whirring in some of the low gears, we subconsciously interpret that as vast quantities of energy being wasted. I'd agree with that 100%...the sound *has* to be working on my mind - although the second one I bought seems less noisy - they're using a different oil now and we'll see when I change the old hub to the new oil. Finally, as to reliability, I do remember Rohloff boasting a year or two ago that they never had the inner guts of a Speedhub fail in service, Stay tuned - I'm working on being the first. Just switched from a 34-tooth ring (not recommended by Rohloff) to a 32-tooth ring (even more not recommended...). Even so I'm 220, I'm in early geezerhood and I can't imagine that even with 32 on the front that I'm putting anywhere near the stress on the thing that a couple of reasonably fit tandem riders would. ----------------------- PeteCresswell |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
newbie question re shifting | Richard Stanz | General | 1 | October 13th 03 12:05 AM |
best internal shifting hub? | Khoomei | General | 17 | August 1st 03 07:35 PM |
Shifter not Shifting right. Anyone have this prolem before? - shimano.jpg (0/1) | B. Sanders | General | 1 | July 21st 03 05:25 AM |
Why has shifting improved? | David L. Johnson | General | 4 | July 15th 03 01:46 PM |