|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
SRAM Dual Drive 3x9
Hello All,
Does anyone have experience with the SRAM Dual Drive 3x9? Is it a replacement for the more conventional freewheel/chainring setup? Can you keep the chainrings if you already have them to increase the gear range? Any info about this system would be appreciated. Thanks, Jeff |
Ads |
#2
|
|||
|
|||
I have the dual drive with an 8 soeed cassette. It basically
substitutes an internally geared, three speed, rear hub for the front derailleur and triple chainrings and then compliments that with an eight speed cassette. This gives you the same number of gears as your typical, 8 speed triple. In this case (3 x 8 , or 24 gear combinations). There is also a normal derailleur to shift the chain among the eight cassette cogs. You shift the derailleur with a twist-shift grip, and the internal hub gears with a thumb shifter. A nice feature of this system is that you can shift the three internal hub gears while at a standstill. That way, if you find yourself stopped at a light and in too high a gear, just click down and you are good to go. You can see the shifters he http://tinypic.com/9jzjog.jpg Here is what shifter box that shifts the internal gears looks like: http://tinypic.com/9jzjts.jpg Another advantage is that it=92s a clean-looking design, with one chainring and no derailleur in the front. The one-handed operation of all the gears is also an advantage, in my opinion. Here is a photo of the front chainring, which comes with dual-sided chainring guards on my bike: http://tinypic.com/9jzjv9.jpg |
#3
|
|||
|
|||
"rBOB" writes:
I have the dual drive with an 8 soeed cassette. It basically substitutes an internally geared, three speed, rear hub for the front derailleur and triple chainrings and then compliments that with an eight speed cassette. This gives you the same number of gears as your typical, 8 speed triple. In this case (3 x 8 , or 24 gear combinations). There is also a normal derailleur to shift the chain among the eight cassette cogs. You shift the derailleur with a twist-shift grip, and the internal hub gears with a thumb shifter. A nice feature of this system is that you can shift the three internal hub gears while at a standstill. That way, if you find yourself stopped at a light and in too high a gear, just click down and you are good to go. You can see the shifters he http://tinypic.com/9jzjog.jpg I have the Dual Drive with a 9 speed cassette on my Fiero. Works great, in my case with a bar end shifter on my USS. My only gripe is that you can't change the ratio of the 3 hub gears. There is a lot of overlap within the 3x9 gears, and I needed a lower gear. With the normal setup of 3 chainrings in front I would just have changed the smallest ring, giving me a larger range with larger spacing between gears. Now I had to change the single chainring in front which meant that the whole set of gears moved down, meaning my top gear is now a bit low. Something else to get used to: you can use all of the 3x9 gears, no issues with chainline which you would normally have using the smallest ring in front and the smallest cog in the back. Another advantage is that it=92s a clean-looking design, with one chainring and no derailleur in the front. The one-handed operation of all the gears is also an advantage, in my opinion. Here is a photo of the front chainring, which comes with dual-sided chainring guards on my bike: http://tinypic.com/9jzjv9.jpg Yes, that was one fo the things I liked as well: a clean view with no front derailleur. It is possible to have multiple chainrings in front as well, to further expand the range. I have experimented with have 2 chainrings in front without a derailleur, worked fine. Can't say anything about durability yet, I've had it for about a year now and not that many miles. What I understand is that the middle hubgear needs to be well tuned or the hub will wear down quickly - the little box has a mrker to adjust that gear. Roos |
#4
|
|||
|
|||
Can't say anything about durability yet, I've had it for about a year now
and not that many miles. What I understand is that the middle hubgear needs to be well tuned or the hub will wear down quickly - the little box I did not know that. Do have any more info or a link? |
#5
|
|||
|
|||
"rBOB" writes:
Can't say anything about durability yet, I've had it for about a year now and not that many miles. What I understand is that the middle hubgear needs to be well tuned or the hub will wear down quickly - the little box I did not know that. Do have any more info or a link? I can't find any explicit sources about the wearing down if not well adjusted... it's something that people in newsgroups and mailinglists repeat to each other (though the maker of my bike also confirmed it). All the manuals for tuning the gear cable focus on getting the middle gear right, that's what the yellow marker on the connecting box is for. The times that I have cycled with the gear slightly out it certainly didn't feel right... Roos |
#6
|
|||
|
|||
Recently had problems with mine where the first hub gear was spinning both
ways, gears 2 and 3 were fine. Eventually opened it up after months of stalling. Hoping that as i did things wouldn't start popping out left, right and centre. Found that one of the compression springs had gone awry and needed replacing and am now waiting for the replacement in the post. Having taken it apart i now feel more confident about taking said bike abroad and its actually fairly straight forward servicing the hub as long as you are reasonable handy. Fergus "Jeff Grippe" jeff@door7 wrote in message ... Hello All, Does anyone have experience with the SRAM Dual Drive 3x9? Is it a replacement for the more conventional freewheel/chainring setup? Can you keep the chainrings if you already have them to increase the gear range? Any info about this system would be appreciated. Thanks, Jeff |
#7
|
|||
|
|||
"None" wrote
opened [internal gear hub] up after months of stalling. [...] am now waiting for the replacement [part] in the post. Having taken it apart i now feel more confident about taking said bike abroad and its actually fairly straight forward servicing the hub as long as you are reasonable handy. The real test is how many "extra" parts you have once you put it back together! %^) I have a Sachs 3x7 on my '98 BikeE,-- not tons of miles, but not a problem, so far. Good to hear it may be maintainable by mere mortals. Jon Meinecke |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
dual drive single-speed powercranker, cheap!? | [email protected] | Techniques | 12 | February 3rd 05 02:01 PM |
New SRAM MTN bike parts...CHEAP | aram bayzaee | Marketplace | 0 | November 26th 04 01:10 AM |
New bicycle idea | Bob Marley | General | 49 | October 7th 04 05:20 AM |
"Liquid Drive" bike prototype at auction | Chalo | General | 86 | December 3rd 03 05:41 AM |
"Liquid Drive" bike prototype at auction | Chalo | Techniques | 87 | December 3rd 03 05:41 AM |