Can Too High Gears be Lowered on SRAM Dualdrive?



A

Artemisia

Guest
Hi All!

Back safe and sound from Provence and first major tour on the recumbent
trike.

Among the technical issues I noticed, this trike, which has a 27-speed
SRAM Dualdrive shifter (three SRAM gears that can be shifted at a
standstill plus a derailleur with nine gears on it) is geared rather
stiff. I spend a lot of time in I-1, and never practically go beyond
III-6, even on the last day when I found myself on the Nationale 7, a
dual carriageway where trikes fear to tread! Comfortable cruising on
flat straight roads is at around III-4 or II-5. The last two gears seem
so high that I cannot see a use for them, since at those speeds,
downhill, I tend not to pedal anyway.

My favorite upright also has a SRAM Dualdrive, but with only 7 plates on
the derailleur. On this bike, I often use the highest gear.

I should mention that the cranks have been changed on the trike which is
now fitted with special short cranks, to go with my medium height. But I
was told one effect of this is that the gears might go stiffer.

The lowest gear is not really low enough to get me up my nightmare hill
on the way to work. I have to push furiously and can only manage a few
strokes before giving up to take a breather.

Now I have heard of people apparently changing the plates on a
derailleur to raise or lower the gear set. So I want to know, before I
get in touch with the Darth, if the request is feasible, if it is easy
or exorbitantly complicated to do, and what sort of price range are we
talking about.

I'm afraid also of disappointing my Darth, because when I bought the
trike in November we were discussing fitting him with a Schlumpf
Mountain Gear in addition to the SRAM. This would cost some 400€ extra,
and of course would add weight and fiddle. Is this a better solution, or
should I prefer substituting the original SRAM cassette for a lower version?

Thanks for your opinions - you people are so helpful!

EFR
Back doing laundry in sweltering Isle de France
 
Artemisia wrote:
> Now I have heard of people apparently changing the plates on a
> derailleur to raise or lower the gear set. So I want to know, before I
> get in touch with the Darth, if the request is feasible, if it is easy
> or exorbitantly complicated to do, and what sort of price range are we
> talking about.


Should be possible to get a new 9spd cassette. Cheaper thing to do
probably would be to simply get a smaller chainring (front gear)

\\paul
--
Paul M. Hobson
..:change the f to ph to reply:.
 
Paul M. Hobson wrote:

> Should be possible to get a new 9spd cassette. Cheaper thing to do
> probably would be to simply get a smaller chainring (front gear)


No front gears with a SRAM Dualdrive, though.

EFR
Ile de France
 

> Paul M. Hobson wrote:
>> Should be possible to get a new 9spd cassette. Cheaper thing to do
>> probably would be to simply get a smaller chainring (front gear)


Artemisia wrote:
> No front gears with a SRAM Dualdrive, though.


No gears that you can change while riding, yes. But you have a crank
with a chainwheel up front where the pedals are. Getting a smaller
chainring will lower the gearing of all gear combinations and cost $25
to $40 (US).

--
Paul M. Hobson
..:change the f to ph to reply:.
 
Artemisia wrote:
> Paul M. Hobson wrote:
>
>> Should be possible to get a new 9spd cassette. Cheaper thing to do
>> probably would be to simply get a smaller chainring (front gear)

>
> No front gears with a SRAM Dualdrive, though.
>
>


The chainring is a gear
 
Paul M. Hobson wrote:

> No gears that you can change while riding, yes. But you have a crank
> with a chainwheel up front where the pedals are. Getting a smaller
> chainring will lower the gearing of all gear combinations and cost $25
> to $40 (US).


Cool! I'll try to find out more.

EFR
Ile de France
 
Artemisia wrote:

> The lowest gear is not really low enough to get me up my nightmare hill
> on the way to work. I have to push furiously and can only manage a few
> strokes before giving up to take a breather.


How often do you cycle to work?
and did you cycle to work during winter?

If you have recently started cycling to work after taking a long winter
break, it might be worth persevering, as your leg muscles will improve,
and in a few week you will wonder what the trouble was.
 
Artemisia wrote:
> Paul M. Hobson wrote:
>
>> Should be possible to get a new 9spd cassette. Cheaper thing to do
>> probably would be to simply get a smaller chainring (front gear)

>
> No front gears with a SRAM Dualdrive, though.
>

Not as stock. However, if your trike has a derailer post, adding a
triple crank and front shifter is easy (though likely a 100-200 Euros).

However, Paul Hobson's suggestion of a smaller chainring is entirely
sensible if you currently have high gears you never use.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
 
In article <[email protected]>, Martin
[email protected] says...

> If you have recently started cycling to work after taking a long winter
> break, it might be worth persevering, as your leg muscles will improve,
>

Not much point having better leg muscles if your knees have exploded ...
 
Paul M. Hobson wrote:
>
>> Paul M. Hobson wrote:
>>> Should be possible to get a new 9spd cassette. Cheaper thing to do
>>> probably would be to simply get a smaller chainring (front gear)

>
> Artemisia wrote:
>> No front gears with a SRAM Dualdrive, though.

>
> No gears that you can change while riding, yes. But you have a crank
> with a chainwheel up front where the pedals are. Getting a smaller
> chainring will lower the gearing of all gear combinations and cost $25
> to $40 (US).


As Paul says...

Roos' Dual-Drive equipped touring 'bent sports a 52 tooth front
chainring if we're going to the NL, but a 42 tooth one at home where the
hills are more freely available.

Changing from the 52 to the 42 gives a ~20% reduction to each of the
gears. There's no reason not to go /very/ low on a trike, as you're not
going to have balance issues at low speed.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/
 
In news:[email protected],
Peter Clinch <[email protected]> tweaked the Babbage-Engine to tell
us:

> Changing from the 52 to the 42 gives a ~20% reduction to each of the
> gears. There's no reason not to go /very/ low on a trike, as you're
> not going to have balance issues at low speed.


Though you /may/ run out of traction, as I discovered to my cost 2/3 of the
way up the Koppenberg a few years ago :-(

--
Dave Larrington
<http://www.legslarry.beerdrinkers.co.uk>
I have a shell collection, have you seen it? I keep it scattered
on the world's beaches.
 
Peter Clinch wrote:

> Roos' Dual-Drive equipped touring 'bent sports a 52 tooth front
> chainring if we're going to the NL, but a 42 tooth one at home where the
> hills are more freely available.


That's interesting. Is it easy to swap around like that? I know Roos has
the privilege of living with a seasoned bike expert, and perhaps is one
herself, but in my case the Darth is quite a distance away. Does not the
chain need shortening or lengthening when you change the spec on the
chainring?

EFR
Ile de France
 
Dave Larrington wrote:

> Though you /may/ run out of traction, as I discovered to my cost 2/3 of the
> way up the Koppenberg a few years ago :-(


How's that - wheels spinning around in place? Would this be because of
slippery or muddy roads, or is it a mechanical problem? Could you regain
traction by gearing up and then down again?

Cheers,

EFR
Ile de France
 
Artemisia wrote:

> That's interesting. Is it easy to swap around like that? I know Roos has
> the privilege of living with a seasoned bike expert, and perhaps is one
> herself


She's pretty much as competent as me, and while you may have me as a
"seasoned bike expert" that doesn't make me a great mechanic by any
stretch of the imagination! Nevertheless, it's pretty straightforward
by our fairly, but not spectacularly, low standards.

You unhook the chain from the chainwheel, undo the bolts holding the
chainwheel onto the crank, remove it, put the new one in place and
replace the bolts. If there's a chain protector disc you'll probably
have to take that off and put it back on too, but again it's just a case
of turning bolts.

> Does not the
> chain need shortening or lengthening when you change the spec on the
> chainring?


Potentially: to some extent the chain tensioner at the back will take up
the slack, but you may put it over its limits, depending on the size of
the step. It's easy enough to find out empirically: if your gears start
giving trouble, especially the higher ones, you'll probably need to
shorten the chain a little. That's quite easy with a chain tool. If
you get one, ask at the shop whether they have a spare bit of old chain
to practise on. I use one of Park's "foolproof" ones, and I haven't
managed to bugger it up yet, despite only using it once a blue moon. If
it's a bit scary then /any/ bike shop should be able to do the job for
you in minutes, if not seconds.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/
 
Artemisia wrote:
> Dave Larrington wrote:
>
>> Though you /may/ run out of traction, as I discovered to my cost 2/3
>> of the way up the Koppenberg a few years ago :-(

>
> How's that - wheels spinning around in place? Would this be because of
> slippery or muddy roads, or is it a mechanical problem? Could you regain
> traction by gearing up and then down again?


While it's worse on muddy roads, make any road steep enough and the
wheel will slip, simply a matter of not enough friction. You could
change up, but then it might be simply too hard to move the pedals!

It's worth noting that this is only a problem on /seriously/ steep hills
(see http://en.wikipedia.org/wiki/Koppenberg). But with muddy tracks
it's quite easy to run out of traction. At which point you get off and
push...

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/
 
Peter Clinch <[email protected]> wrote:

> Artemisia wrote:
> > Dave Larrington wrote:
> >
> >> Though you /may/ run out of traction, as I discovered to my cost 2/3
> >> of the way up the Koppenberg a few years ago :-(

> >
> > How's that - wheels spinning around in place? Would this be because of
> > slippery or muddy roads, or is it a mechanical problem? Could you regain
> > traction by gearing up and then down again?

>
> While it's worse on muddy roads, make any road steep enough and the
> wheel will slip, simply a matter of not enough friction. You could
> change up, but then it might be simply too hard to move the pedals!
>

the lane nr my folks house as it gets steeper gets worse, more holes and
during winter/spring covered with shale,and well what ever washes off
the hills. so bit of balancing act getting enought traction and so one
can still turn the cranks, still it's not a hill one uses to get from A
to B more for the i'll beat it. heh some of the folk in the village
woun't drive their cars up it. it averages 20% with peaks well into the
30% mark along with nice slippy bits, its great fun attually in a hot
sweaty, why am i doing this? kind of way

> It's worth noting that this is only a problem on /seriously/ steep hills
> (see http://en.wikipedia.org/wiki/Koppenberg). But with muddy tracks
> it's quite easy to run out of traction. At which point you get off and
> push...
>

looks fun in a jiggly sort of way.


> Pete.


roger
--
www.rogermerriman.com
 
Peter Clinch wrote:

> It's worth noting that this is only a problem on /seriously/ steep hills
> (see http://en.wikipedia.org/wiki/Koppenberg). But with muddy tracks
> it's quite easy to run out of traction. At which point you get off and
> push...


My hill is seriously steep. And it's not practical to get out and pull
because on that kind of incline the SPD shoes just slip and slip, and
the bike is so heavy that it pulls me over.

I have had the trike lose traction on the dirt path that immediately
follows or precedes the killer hill. But here it was just a case of too
deep muddy goo.

EFR
Ile de France
 
Artemisia wrote:
> Peter Clinch wrote:
>
>> It's worth noting that this is only a problem on /seriously/ steep hills
>> (see http://en.wikipedia.org/wiki/Koppenberg). But with muddy tracks
>> it's quite easy to run out of traction. At which point you get off and
>> push...

>
> My hill is seriously steep.


How seriously? Koppenberg is famously difficult for
/professionals/. What's the actual gradient? There should be no
trouble with traction on a typically surfaced 20% hill, and those
are very unusual.

> And it's not practical to get out and pull
> because on that kind of incline the SPD shoes just slip and slip


There shouldn't be any particular trouble walking up a 20% hill in
a pair of recessed-cleat shoes as long as it isn't an expecially
slippy road.

> the bike is so heavy that it pulls me over.


It's a tricycle, it can't fall over, and if it can't fall over
it'll have trouble pulling you with it!

> I have had the trike lose traction on the dirt path that immediately
> follows or precedes the killer hill. But here it was just a case of too
> deep muddy goo.


Mud, ice, diesel, wet leaves, drain covers can have you lose
traction on level ground. You're never going to resolve all
traction problems, but that doesn't make bikes/trikes unusable.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/
 
In news:[email protected],
Peter Clinch <[email protected]> tweaked the Babbage-Engine to tell
us:
> Artemisia wrote:
>> Peter Clinch wrote:
>>
>>> It's worth noting that this is only a problem on /seriously/ steep
>>> hills (see http://en.wikipedia.org/wiki/Koppenberg). But with
>>> muddy tracks it's quite easy to run out of traction. At which
>>> point you get off and push...

>>
>> My hill is seriously steep.

>
> How seriously? Koppenberg is famously difficult for
> /professionals/. What's the actual gradient? There should be no
> trouble with traction on a typically surfaced 20% hill, and those
> are very unusual.


Koppenberg is about 20%; the problem is that there is sand between the
cobblestones, so if the rear wheel gets into a longitudinal gap, you are
stuffed. I've done 25% a few times, most notably Bushcombe Lane:

http://preview.tinyurl.com/5mp5hu
(redirects to streetmap.co.uk)

at the start of the Cotswold Corker. I only had traction issues where it
starts to level out, due to the mud, grit, water and skog(tm) which are
frequently to be found strewn about the minor roads of the BRITONS' England
in the month of February. On the steeper bits lower down I was OK, except
for having to avoid those unable to remain upright and who were thus
toppling gracelessly into the hedge, or the front gardens of householders
unfortunate enough to live on the route.

--
Dave Larrington
<http://www.legslarry.beerdrinkers.co.uk>
I am Wan, for I am pursued by the Army of Plums.
 
Dave Larrington wrote:
> In news:[email protected],
> Peter Clinch <[email protected]> tweaked the Babbage-Engine to tell
> us:
>> Artemisia wrote:
>>> Peter Clinch wrote:
>>>
>>>> It's worth noting that this is only a problem on /seriously/ steep
>>>> hills (see http://en.wikipedia.org/wiki/Koppenberg). But with
>>>> muddy tracks it's quite easy to run out of traction. At which
>>>> point you get off and push...
>>> My hill is seriously steep.

>> How seriously? Koppenberg is famously difficult for
>> /professionals/. What's the actual gradient? There should be no
>> trouble with traction on a typically surfaced 20% hill, and those
>> are very unusual.

>
> Koppenberg is about 20%; the problem is that there is sand between the
> cobblestones, so if the rear wheel gets into a longitudinal gap, you are
> stuffed. I've done 25% a few times, most notably Bushcombe Lane:


Longstaff "double drive" sounds helpful here.

BugBear