Dark Side Trike: One Hand Actuation?

Artemisia said:

Another option on the Scorpion FX price list: I can have my brakes and
shifters set up either like this:

"disc brakes MAGURA BIG hydraulic, one lever actuates both front
brakes, rear: Avid V-brake with Velcro-strap as parking brake"

or like this:

"Onehand actuation brake and shifters MAGURA BIG hydraulic disc
brake / DualDrive-drive train with bar end shifter and twist shifter /
parking brake with thumbshifter, right hand or left"

I can't really understand what each option implies.

Ask HPVel themselves to clarify: they know best what they can do and
their factory options.

Quoted message said:

Is it an advantage
to have just one hand doing _all_ the work? If all brakes are actuated
by just one hand, one cannot signal with that hand and brake at the
same time, for example when turning?

Yes and no. With one hand actuation you completely remove brake steer,
the tendency for the bike to turn one way when you only use the brake on
that side. It's not a big problem on the Scorpion, but it certainly
happens to some degree.

I don't know if you can get one hand actuation but with a lever on each
side... again, ask HP Vel to clarify.

Quoted message said:

I'm also assuming that, being right-handed, I should have the one-hand
actuation set up for the right hand, if I decide to go that way.

I would put it on the right but not for that reason: a right turn signal
is not actually very important most of the time if you're on the right
of the road.

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 hidden] http://www.dundee.ac.uk/~pjclinch/

Artemisia said:

Another option on the Scorpion FX price list: I can have my brakes and
shifters set up either like this:

"disc brakes MAGURA BIG hydraulic, one lever actuates both front
brakes, rear: Avid V-brake with Velcro-strap as parking brake"

or like this:

"Onehand actuation brake and shifters MAGURA BIG hydraulic disc
brake / DualDrive-drive train with bar end shifter and twist shifter /
parking brake with thumbshifter, right hand or left"

I can't really understand what each option implies. Is it an advantage
to have just one hand doing _all_ the work?

It is if you only have one (working) arm.....

If you look at the SRAM website (http://www.sram-imotion.com/) you
will see that dual drive II now comes with a single shifter (twist for
cassette, knob for hub), though that might make shifting on a trike
interesting? I'd want to try before buying, or at least get
clarification from HPV on just what is fitted.

Artemisia said:

brakes, rear: Avid V-brake with Velcro-strap as parking brake"

By the way, a parking brake is going to be absolutely necessary, as I
will be stopping frequently to rest on steep slopes. Also I will need
to get out of trike on steep slopes to get around gates and bollards,
and I don't want it taking off on its own.

Sorry, no expert knowledge of this and I don't want to worry you, I'm
just curious - is the parking brake designed to stop the weight of
bike + rider rolling back on a steep hill? I've seen descriptions of
parking brakes before and thought velcro straps sounded rather feeble
then decided they were just meant to stop the unattended bike rolling
away.

Rob

squeaker said:

If you look at the SRAM website (http://www.sram-imotion.com/) you
will see that dual drive II now comes with

There's an idiotic website: I can't even get past the flash screen. Can
you? Not impressed with the design of _tat_.

EFR
Ile de France

Artemisia said:

There's an idiotic website: I can't even get past the flash screen. Can
you? Not impressed with the design of _tat_.

I meant _that_

EFR

Peter Clinch said:

Yes and no. With one hand actuation you completely remove brake steer,
the tendency for the bike to turn one way when you only use the brake on
that side. It's not a big problem on the Scorpion, but it certainly
happens to some degree.

HPV claim they have no brake steer on the Scorpion. I think I read
that having each brake actuated by a different hand means you can
brake more on the inside of a curve. I suppose a skilled rider could
ride more skillfully with 2-hand actuation. The Magura Bigs are always
1-hand actuated but the Martas, supposedly even higher end, are 2-
handers.

EFR
Ile de France

Artemisia said:

squeaker said:

If you look at the SRAM website (http://www.sram-imotion.com/) you
will see that dual drive II now comes with

There's an idiotic website: I can't even get past the flash screen. Can
you? Not impressed with the design of _tat_.

There are pictures of the DD shifters here then
www.easystreetrecumbents.com/stuff/hubs.html

They only show the 8x3 version (they've goofed and used the same
picture twice I think) but the 9x3 is similar but with a different
indicator.
--
Phil Cook looking north over the park to the "Westminster Gasworks"

Artemisia said:

HPV claim they have no brake steer on the Scorpion.

Well, I took one down a steep hill and put on one brake only and it did
steer to that side. Not to a significant or in any worrying degree
(compare to a Kettweisel, where you can do handbrake turns!), but it did
happen.

Quoted message said:

I think I read
that having each brake actuated by a different hand means you can
brake more on the inside of a curve. I suppose a skilled rider could
ride more skillfully with 2-hand actuation.

In theory, yes, but in practice I think it's a non-issue.

Quoted message said:

The Magura Bigs are always
1-hand actuated but the Martas, supposedly even higher end, are 2-
handers.

"High endedness" is nothing to do with why they're single actuation.
BIGs are designed for non-*bi*cycle applications including quad bikes
and actually come in distinct left and right mounts. Martas are
designed for bikes where independent front and rear actuation makes a
lot more sense (mount one upside down to get different sides IIRC).

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 hidden] http://www.dundee.ac.uk/~pjclinch/

Quoted message said:

Artemisia said:

brakes, rear: Avid V-brake with Velcro-strap as parking brake"

By the way, a parking brake is going to be absolutely necessary, as I
will be stopping frequently to rest on steep slopes. Also I will need
to get out of trike on steep slopes to get around gates and bollards,
and I don't want it taking off on its own.

Sorry, no expert knowledge of this and I don't want to worry you, I'm
just curious - is the parking brake designed to stop the weight of
bike + rider rolling back on a steep hill? I've seen descriptions of
parking brakes before and thought velcro straps sounded rather feeble
then decided they were just meant to stop the unattended bike rolling
away.

Velcro strap parking brakes are a fudge. For better to have one of
these where you can engage and disengage the brake one handed.
http://www.christianiabikes.com/images/websidebilleder/parkeringsbremse.jpg
To apply you pull on the brake lever and push the red pawl with your
first finger. To release pull the brake and pull the pawl with your
first finger.

The only problem I can see is where to get one on its own.
--
Phil Cook looking north over the park to the "Westminster Gasworks"

Phil Cook said:

Quoted message said:

Artemisia said:

brakes, rear: Avid V-brake with Velcro-strap as parking brake"

By the way, a parking brake is going to be absolutely necessary, as
I will be stopping frequently to rest on steep slopes. Also I will
need to get out of trike on steep slopes to get around gates and
bollards, and I don't want it taking off on its own.

Sorry, no expert knowledge of this and I don't want to worry you, I'm
just curious - is the parking brake designed to stop the weight of
bike + rider rolling back on a steep hill? I've seen descriptions of
parking brakes before and thought velcro straps sounded rather feeble
then decided they were just meant to stop the unattended bike rolling
away.

Velcro strap parking brakes are a fudge. For better to have one of
these where you can engage and disengage the brake one handed.
http://www.christianiabikes.com/images/websidebilleder/parkeringsbremse.jpg
To apply you pull on the brake lever and push the red pawl with your
first finger. To release pull the brake and pull the pawl with your
first finger.

The only problem I can see is where to get one on its own.

For cable operation, ask ICE.
They fit push-button parking locks to the brakes on their TRICE trikes.

Assuming they have lots of bits, I guess they would sell one as a spare.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

In uk.rec.cycling Peter Clinch twisted the electrons to say:

Quoted message said:

Artemisia said:

HPV claim they have no brake steer on the Scorpion.

Well, I took one down a steep hill and put on one brake only and it did
steer to that side. Not to a significant or in any worrying degree
(compare to a Kettweisel, where you can do handbrake turns!), but it did
happen.

<nods> Not ridden a Scorpion, but ICE claim that their range is free
from brake steer and I'd dispute that. Like you though, I would
certainly say it was not present to any significant or worrying degree.
--
These opinions might not even be mine ...
Let alone connected with my employer ...