gearing for a trike tandem



A

Avgrin

Guest
I'm considering SRAM Dualdrive 27 for a touring tandem trike
with 20" drive wheel and two chain rings 30-50 on a 155mm
crank. Does anyone have any experience with similar setup?
I'd appreciate any advice on this matter.
 
avgrin wrote:

> I'm considering SRAM Dualdrive 27 for a touring tandem
> trike with 20" drive wheel and two chain rings 30-50 on a
> 155mm crank. Does anyone have any experience with similar
> setup? I'd appreciate any advice on this matter.

Greenspeed uses the DualDrive hub on their GTT tandem.

I am not aware if SRAM rates the DualDrive for tandem use,
but putting the cranks out of phase will reduce the peak
torque on the hub.

The shifting on a 50-30 crank may be problematic - why not
use a standard 52-42-30 crank?

--
Tom Sherman – Quad City Area
 
I have one on my Optima Dolphin and really like it.
I have a single front ring -50tooth- and the gear range is better than a 3
ring setup without the dualdrive hub.
I agree with Tom S. about the 2 ring,may as well use 3 rings ,you will have
a very large gear range.
Check it out at on one of the gear range calculators.
Ben fox
"avgrin" <[email protected]> wrote in message
news:[email protected]...
> I'm considering SRAM Dualdrive 27 for a touring tandem
> trike with 20" drive wheel and two chain rings 30-50 on a
> 155mm crank. Does anyone have any experience with similar
> setup? I'd appreciate any advice on this matter.
 
Ben Fox wrote:
> I have one on my Optima Dolphin and really like it. I have
> a single front ring -50tooth- and the gear range is better
> than a 3 ring setup without the dualdrive hub. I agree
> with Tom S. about the 2 ring,may as well use 3 rings ,you
> will have a very large gear range. Check it out at on one
> of the gear range calculators.

Here is one that is easy to use:
<http://www.sheldonbrown.com/gears/>.

--
Tom Sherman – Quad City Area
 
B"H Hi Tom and Ben thank you for your input. I agree that
50-30 might be not a very crisp shifting and the range is
too wide: 13 - 124. My aim is to get 15 to about 100 range.
Actually a 36 chain ring gives 15 to 89 range. This is not
enough for the high gear, so if I go to 34-42 it'll shift
better and will produce a very nice range of 15 - 104. The
reason for the double is because I already have 155mm.
double crank.

Ben, how is reliability and maintenance on the Doubledrive?
Does it have much energy loss in low and high gears?

Thank you, Victor

"Ben Fox" <[email protected]> wrote in message
news:<[email protected]>...
> I have one on my Optima Dolphin and really like it. I have
> a single front ring -50tooth- and the gear range is better
> than a 3 ring setup without the dualdrive hub. I agree
> with Tom S. about the 2 ring,may as well use 3 rings ,you
> will have a very large gear range. Check it out at on one
> of the gear range calculators. Ben fox "avgrin"
> <[email protected]> wrote in message
> news:[email protected]...
> > I'm considering SRAM Dualdrive 27 for a touring tandem
> > trike with 20" drive wheel and two chain rings 30-50 on
> > a 155mm crank. Does anyone have any experience with
> > similar setup? I'd appreciate any advice on this matter.
 
avgrin wrote:

> B"H Hi Tom and Ben thank you for your input. I agree that
> 50-30 might be not a very crisp shifting and the range is
> too wide: 13 - 124. My aim is to get 15 to about 100
> range. Actually a 36 chain ring gives 15 to 89 range. This
> is not enough for the high gear, so if I go to 34-42 it'll
> shift better and will produce a very nice range of 15 -
> 104. The reason for the double is because I already have
> 155mm. double crank....

I would rethink the 15-inch low gear. Tandem trikes can be
slow climbers, especially with a touring load, and since
balance is not an issue, very low gears are usable. A 22-32-
44 MTB rings or 24-34-46 touring rings would provide a
gearing range suitable for almost all circumstances.

--
Tom Sherman – Quad City Area
 
For the short time I've had the Dualdrive ,I would say that I haven't
noticed any enery loss in low and high gears.
If you have your trike geared properly most of you cruising would be done in
the midgear of the dualdrive.
As far as reliability,I haven't had it long enough to say,but i know the old
3x7 hub they sold was very reliable.
Ben
"avgrin" <[email protected]> wrote in message
news:[email protected]...
> B"H Hi Tom and Ben thank you for your input. I agree that
> 50-30 might be not a very crisp shifting and the range is
> too wide: 13 - 124. My aim is to get 15 to about 100
> range. Actually a 36 chain ring gives 15 to 89 range. This
> is not enough for the high gear, so if I go to 34-42 it'll
> shift better and will produce a very nice range of 15 -
> 104. The reason for the double is because I already have
> 155mm. double crank.
>
> Ben, how is reliability and maintenance on the
> Doubledrive? Does it have much energy loss in low and
> high gears?
>
> Thank you, Victor
>
>
> "Ben Fox" <[email protected]> wrote in message
news:<[email protected]>...
> > I have one on my Optima Dolphin and really like it. I
> > have a single front ring -50tooth- and the gear range is
> > better than a
3
> > ring setup without the dualdrive hub. I agree with Tom
> > S. about the 2 ring,may as well use 3 rings ,you will
have
> > a very large gear range. Check it out at on one of the
> > gear range calculators. Ben fox "avgrin"
> > <[email protected]> wrote in message
> > news:[email protected]...
> > > I'm considering SRAM Dualdrive 27 for a touring tandem
> > > trike with 20" drive wheel and two chain rings 30-50
> > > on a 155mm crank. Does anyone have any experience with
> > > similar setup? I'd appreciate any advice on this
> > > matter.
 
B"H
SRAM doesn't recommend DoubleDrive for Tandems:

Thanks for contacting SRAM. We don't recommend the DualDrive
(or any of our hubs) for tandem use. They are not designed
to handle the high loads placed by this application. Any of
our hubs that are used in a high load application like
tandem/tricycle use, racing, or mountain biking will not
carry a warranty and will not be supported by SRAM.

Happy Trails.
----------------------------------------

Mike Reisenleiter SRAM Technical Support
[email protected]
 
On 23 May 2004 00:17:07 -0700, [email protected] (avgrin) wrote:

>I'm considering SRAM Dualdrive 27 for a touring tandem
>trike with 20" drive wheel and two chain rings 30-50 on a
>155mm crank. Does anyone have any experience with similar
>setup? I'd appreciate any advice on this matter.

I am just getting into the shorter cranks, though not on
the tandem. I love them. You will likely spin a lot faster
and not require as high of gearing as you might otherwise,
assuming your stoker also like high speed spinning, but
you will probably want to gear down as low as you can
because torque does seem to decrease a bit with the
shorter cranks. Especially on my 140's, the 155's I also
use are not nearly so bad.

I have the old version of the Dual Drive on my 1999 GTT. It
has not broken down and left me stranded. I do sometimes
ride with a very powerful stoker and we can cruise in the
18-20 range. It is heavy, very heavy rotating mass. When I
took the dual drive off another bent, replacing it with a
regular rear wheel, I was faster accelerating and faster up
hills. I would love to replace it on my GTT.

I have had far more problems with shifting the regular part
of the drive train than on any other tandem I have ridden,
DF or bent. The rear derailluer,a Shimano seems unable to be
adjusted to keep the chain on one gear. We can be cruising
along for a very long way, straight line, smooth road, when
for no apparent reason, we shift, then return back to the
selected cassette ring. I am switching over to SRAM
derailluers because I understand they use a stronger spring.

I really have to moderate my power, and even this stoker
too, or we will cause the timing chains to jump out of
phase. I can do this up to about 12-15 mph just by trying to
sprint. New chains helped a bit, new chain rings a bit more.
Alignment is critical for the boom, and unfortunately, every
time I transport my GTT the boom has to come off.

Under the grass is always greener department, my current
thought would be to build a good strong, maybe even a non
freewheeling wheel for the rear and devise a mid drive
system, something like Rotator uses, to get the range of
gearing I need. My fantasy holds that shifting will be
smoother with a wider range of gears for the slow crawls
uphill and the fast trips back down, will be stronger
because the wheel will be built without any dish, or
nearly so, and the drive train will have tandem rated
parts so the cranks can be in sync, allowing for faster
acceleration and better climbing. This doesn't address the
cranks skipping though.

For that I think some kind of device that will tension/guide
the chain onto the chain ring would solve, or at least,
minimize the problem.

All that said, of the half dozen or so other bent trike
owners I've talked to, I am the only one experiencing these
problems, so my fantasy solutions may not be of any benefit
to you at all.

Any comments? Anyone?

MikeE
 
Mike Euritt wrote:

> On 23 May 2004 00:17:07 -0700, [email protected]
> (avgrin) wrote:
>
>
>>I'm considering SRAM Dualdrive 27 for a touring tandem
>>trike with 20" drive wheel and two chain rings 30-50 on a
>>155mm crank. Does anyone have any experience with similar
>>setup? I'd appreciate any advice on this matter.
>
>
> I am just getting into the shorter cranks, though not on
> the tandem. I love them. You will likely spin a lot faster
> and not require as high of gearing as you might otherwise,
> assuming your stoker also like high speed spinning, but
> you will probably want to gear down as low as you can
> because torque does seem to decrease a bit with the
> shorter cranks. Especially on my 140's, the 155's I also
> use are not nearly so bad.
>
> I have the old version of the Dual Drive on my 1999 GTT.
> It has not broken down and left me stranded. I do
> sometimes ride with a very powerful stoker and we can
> cruise in the 18-20 range. It is heavy, very heavy
> rotating mass. When I took the dual drive off another
> bent, replacing it with a regular rear wheel, I was faster
> accelerating and faster up hills. I would love to replace
> it on my GTT.
>
> I have had far more problems with shifting the regular
> part of the drive train than on any other tandem I have
> ridden, DF or bent. The rear derailluer,a Shimano seems
> unable to be adjusted to keep the chain on one gear. We
> can be cruising along for a very long way, straight line,
> smooth road, when for no apparent reason, we shift, then
> return back to the selected cassette ring. I am switching
> over to SRAM derailluers because I understand they use a
> stronger spring.
>
> I really have to moderate my power, and even this stoker
> too, or we will cause the timing chains to jump out of
> phase. I can do this up to about 12-15 mph just by trying
> to sprint. New chains helped a bit, new chain rings a bit
> more. Alignment is critical for the boom, and
> unfortunately, every time I transport my GTT the boom has
> to come off.
>
> Under the grass is always greener department, my current
> thought would be to build a good strong, maybe even a non
> freewheeling wheel for the rear and devise a mid drive
> system, something like Rotator uses, to get the range of
> gearing I need. My fantasy holds that shifting will be
> smoother with a wider range of gears for the slow crawls
> uphill and the fast trips back down, will be stronger
> because the wheel will be built without any dish, or
> nearly so, and the drive train will have tandem rated
> parts so the cranks can be in sync, allowing for faster
> acceleration and better climbing. This doesn't address the
> cranks skipping though.
>
> For that I think some kind of device that will
> tension/guide the chain onto the chain ring would solve,
> or at least, minimize the problem.
>
> All that said, of the half dozen or so other bent trike
> owners I've talked to, I am the only one experiencing
> these problems, so my fantasy solutions may not be of any
> benefit to you at all.
>
> Any comments? Anyone?

There is the da Vinci Independent Drive [TM] that could
possibly be adapted to a GTT:
<http://www.davincitandems.com/dv2.html>.

The Rohloff Speedhub 500/14 is rated for tandem use:
<http://www.rohloff.de/index.php?p=PRODUKTE/SPEEDHUB>.

--
Tom Sherman – Quad City Area
 
B"H

Hi Tom,

You are absolutely correct about the Rohloff Speedhub. I am
seriously considering it because a combination of a 16-cog
and 44-chain wheel gives a 15 to 79-gear inch range, which
translates into 2.2 mi/h to 21
mi/h speeds with 50 rpm and 90-rpm corresponding cadences.
I'm also considering of setting up a double chain ring in
front with 44 and 54
c.rs. I'll install 44 c.r. and see how it works, because 54
c.r. gives just 2 more useful gears 85 and 97, which maybe
used very few times (I can e-mail an Excel spreadsheet for
anyone who is interested).

If anyone has any experience about Rohloff Speedhub, or any
comments about the proposed setup, I'd greatly appreciate
your help.

Thank you,

Victor

> There is the da Vinci Independent Drive [TM] that could
> possibly be adapted to a GTT:
> <http://www.davincitandems.com/dv2.html>.
>
> The Rohloff Speedhub 500/14 is rated for tandem use:
> <http://www.rohloff.de/index.php?p=PRODUKTE/SPEEDHUB>.
 
B"H

Hi Mike, Thank you for sharing your GTT experience. I'll
definitely will use shorter cranks.

Do I understand you correctly, that you don’t like
Dualdrive that much on your GTT and would like to replace
it with a regular rear wheel because the Dualdrive
accelerates slower, is less efficient going up the hill,
and creates problems in shifting?

Thank you,

Victor
> >
> >
> >>I'm considering SRAM Dualdrive 27 for a touring tandem
> >>trike with 20" drive wheel and two chain rings 30-50 on
> >>a 155mm crank. Does anyone have any experience with
> >>similar setup? I'd appreciate any advice on this matter.
> >
> >
> > I am just getting into the shorter cranks, though not on
> > the tandem. I love them. You will likely spin a lot
> > faster and not require as high of gearing as you might
> > otherwise, assuming your stoker also like high speed
> > spinning, but you will probably want to gear down as low
> > as you can because torque does seem to decrease a bit
> > with the shorter cranks. Especially on my 140's, the
> > 155's I also use are not nearly so bad.
> >
> > I have the old version of the Dual Drive on my 1999 GTT.
> > It has not broken down and left me stranded. I do
> > sometimes ride with a very powerful stoker and we can
> > cruise in the 18-20 range. It is heavy, very heavy
> > rotating mass. When I took the dual drive off another
> > bent, replacing it with a regular rear wheel, I was
> > faster accelerating and faster up hills. I would love to
> > replace it on my GTT.
> >
> > I have had far more problems with shifting the regular
> > part of the drive train than on any other tandem I have
> > ridden, DF or bent. The rear derailluer,a Shimano seems
> > unable to be adjusted to keep the chain on one gear. We
> > can be cruising along for a very long way, straight
> > line, smooth road, when for no apparent reason, we
> > shift, then return back to the selected cassette ring. I
> > am switching over to SRAM derailluers because I
> > understand they use a stronger spring.
> >
> > I really have to moderate my power, and even this stoker
> > too, or we will cause the timing chains to jump out of
> > phase. I can do this up to about 12-15 mph just by
> > trying to sprint. New chains helped a bit, new chain
> > rings a bit more. Alignment is critical for the boom,
> > and unfortunately, every time I transport my GTT the
> > boom has to come off.
> >
> > Under the grass is always greener department, my current
> > thought would be to build a good strong, maybe even a
> > non freewheeling wheel for the rear and devise a mid
> > drive system, something like Rotator uses, to get the
> > range of gearing I need. My fantasy holds that shifting
> > will be smoother with a wider range of gears for the
> > slow crawls uphill and the fast trips back down, will be
> > stronger because the wheel will be built without any
> > dish, or nearly so, and the drive train will have tandem
> > rated parts so the cranks can be in sync, allowing for
> > faster acceleration and better climbing. This doesn't
> > address the cranks skipping though.
> >
> > For that I think some kind of device that will
> > tension/guide the chain onto the chain ring would solve,
> > or at least, minimize the problem.
> >
> > All that said, of the half dozen or so other bent trike
> > owners I've talked to, I am the only one experiencing
> > these problems, so my fantasy solutions may not be of
> > any benefit to you at all.
> >
> > Any comments? Anyone?
>
> There is the da Vinci Independent Drive [TM] that could
> possibly be adapted to a GTT:
> <http://www.davincitandems.com/dv2.html>.
>
> The Rohloff Speedhub 500/14 is rated for tandem use:
> <http://www.rohloff.de/index.php?p=PRODUKTE/SPEEDHUB>.