SRAM Dual Drive 3x9

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 here:
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’s 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

rBOB said:

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 here:
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.

Quoted message said:

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

Quoted message said:

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?

rBOB said:

Quoted message said:

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

Quoted message said:

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

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
news:[email hidden]...

Quoted message said:

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

"None" <[email hidden]> wrote

Quoted message said:

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