Internal hub gears or derailleur?

My wife and I have just had our bikes stolen. I need to get a new one
for commuting to work and I've been looking at purchasing a hybrid type
bike as I do like to take the bike over rough ground at weekends, forest
paths etc (i.e. still quite gentle).

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed derailleur
systems. Is it practical to use a bike with internal hub gears off road
or is a derailleur system better?

Thanks

Steve C

On Sat, 17 May 2008 10:13:22 +0100
Steve C wrote:

My wife and I have just had our bikes stolen. I need to get a new one
for commuting to work and I've been looking at purchasing a hybrid
type bike as I do like to take the bike over rough ground at
weekends, forest paths etc (i.e. still quite gentle).

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed
derailleur systems. Is it practical to use a bike with internal hub
gears off road or is a derailleur system better?

There's no reason hub gears won't handle moderate off-road use -
they'll generally cope with stray twigs better than derailleurs do. The
downside of hub gears is they tend to weigh more than derailleurs,
they're a little less efficient and don't have as wide a range of
gears. They can also be very expensive. The upside is that a better
chain line can be maintained and all the workings are protected within
the hub.

In article , Steve C wrote:
My wife and I have just had our bikes stolen. I need to get a new one
for commuting to work and I've been looking at purchasing a hybrid type
bike as I do like to take the bike over rough ground at weekends, forest
paths etc (i.e. still quite gentle).

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed derailleur
systems. Is it practical to use a bike with internal hub gears off road
or is a derailleur system better?

A derailleur system will give you a wider range of gears unless your
internal gear hub is the excellent but expensive Rohloff, but for
gentle forest paths I would have thought the 8-speed hub would be
entirely practical. But I haven't actually used one.

Might be worth finding something with a Shimano Alfine 8-spd hub if
you are going to get the bikes mucky, as they claim 'improved
sealing'. (Rolhoff is fine off road, AFAIK.)
Otherwise I can't see the problem with using a hub gear on relatively
mild off-road paths (smooth-ish, no big gradients etc.).

"Rob Morley" wrote in message
news:20080517125551.567983be@bluemoon...
On Sat, 17 May 2008 10:13:22 +0100
Steve C wrote:

My wife and I have just had our bikes stolen. I need to get a new one
for commuting to work and I've been looking at purchasing a hybrid
type bike as I do like to take the bike over rough ground at
weekends, forest paths etc (i.e. still quite gentle).

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed
derailleur systems. Is it practical to use a bike with internal hub
gears off road or is a derailleur system better?

There's no reason hub gears won't handle moderate off-road use -
they'll generally cope with stray twigs better than derailleurs do. The
downside of hub gears is they tend to weigh more than derailleurs,
they're a little less efficient and don't have as wide a range of
gears. They can also be very expensive. The upside is that a better
chain line can be maintained and all the workings are protected within
the hub.

Hub gears are usd in the Thorn expedition range of bikes and I'm sure that
I've seen some hub gearsed MTBs. Although the bikes that I'm referring to
are 14 speed hubs from Rohloff, the principles are the same for any hub
geared ike. There's no mechanisms to damage. Chains tend to last longer
because there's no lateral flex caused by derailleur gears. The makers of
the Thorn range of bikes claim that there's no weight disadvantage when the
gear mechs and levers are compared i.e. derailleur shifters and mechs from
front and rear vs the hub gear. Efficiency isn't really an issue unless one
is trying the extract every last ounce of performance from a bike.

The only downsides that I can think of, and they are minor, is the faff of
removing the rear wheel to replace inner tubes when suffering from a
puncture and the need to adjust the rear wheel periodically to maintain
chain tension. Thorn bikes have neat fixes to attend to these issues i.e.
eccentric bottom bracket mount and some cleaver connectors to facilitate
wheel removal. I don't know how other manufacturers approach these two
problems.

Alan Braggins wrote:

A derailleur system will give you a wider range of gears unless your
internal gear hub is the excellent but expensive Rohloff, but for
gentle forest paths I would have thought the 8-speed hub would be
entirely practical. But I haven't actually used one.

I have, I did an off road thing in Derbyshire two years ago on my wife's
Nexus8 bike. It's fine, first is really low, top is fine for road
work... the efficiency thing I would debate: the hub gear is always
running in clean grease rather than road crud, so in actual use I would
imagine they are on a par unless you are a meticulous bike cleaner :-)
and as for range of gears, well.. the hub doesn't have overlap and the
spacing is even - ICBA to dig out the numbers but I think Mrs B's
8-speed is not too far off being the equal of a 27 speed chain bully...

YMMV but I think hub gears are really, really good... but taking the
back wheel off is, indeed, an arse...

T

Steve C wrote:
My wife and I have just had our bikes stolen. I need to get a new one
for commuting to work and I've been looking at purchasing a hybrid type
bike as I do like to take the bike over rough ground at weekends, forest
paths etc (i.e. still quite gentle).

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed derailleur
systems. Is it practical to use a bike with internal hub gears off road
or is a derailleur system better?

There's now a few complete mountain bikes that use the Shimano Alfine
hub gears (eg from Charge or Genesis), so I think it would work fine for
off road.
It does mean the back wheel would be a bit heavier than with a
derailleur, which might affect handling a bit (though probably not a
problem for forest paths etc).

Though I notice that SRAM say the i-Motion 9 is 'not approved' for
mountain bike use. I'm sure it would work fine for gentle off road, it
just might not be covered by the warranty if it breaks.

In article , vernon wrote:
the Thorn range of bikes claim that there's no weight disadvantage when the
gear mechs and levers are compared i.e. derailleur shifters and mechs from
front and rear vs the hub gear.

Though on a full suspension bike the front mech and chainrings will
be sprung weight and the hub unsprung, hence the G-Boxx design with
the "hub" gear in the frame.
On a commuting bike on modest forest paths that really doesn't matter
at all though.

Alan Braggins wrote:
In article , Steve C wrote:
My wife and I have just had our bikes stolen. I need to get a new one
for commuting to work and I've been looking at purchasing a hybrid type
bike as I do like to take the bike over rough ground at weekends, forest
paths etc (i.e. still quite gentle).

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed derailleur
systems. Is it practical to use a bike with internal hub gears off road
or is a derailleur system better?

A derailleur system will give you a wider range of gears unless your
internal gear hub is the excellent but expensive Rohloff,
or even
http://www.sheldonbrown.com/harris/nuvinci.html

Some commuting bikes (Giant Escape for example) come with 8 speed
internal gear hubs whereas others (Giant CRS) have 27 speed derailleur
systems. Is it practical to use a bike with internal hub gears off road
or is a derailleur system better?


Hub gears every time, no doubt about it. Non over-lapped evenly
spaced perfect first time quick sequential shifts. No more missed
shifts, spurious shifts, clanking chains, chain suck, broken mechs,
bent hangers, de-gunking jockey wheels, noisy drive-trains or
continual fettling/adjustment. I miss dérailleurs like a hole in the
head.

Don't worry about adjusting the gears when re-placing the wheel
either. For a Sturmey Archer it takes about a minute and it's a dead
easy job. For a Rohloff you don't need to do anything except
selecting the top gear.

Three gears is plenty enough for commuting, any more is a bonus.

Regards,

Duncan