internal hub gearing for mtb

[Dave Larrington]

David Nutter wrote:

> Howabout a 7 speed hub and one of those Mountain Drive things? I have no if they're any good, but
> the idea of a planetary gear inside the chainset seems quite nifty to me.

Rohloff advise against using a Mountain Drive with their hub, and they also advise a chainring size
of 2.4 x the rear sprocket size. I woudn't be surprised if other hub manufacturers cover their tails
in the same manner, though they may well be erring on the side of conservatism. Just don't expect
any warranty claims to be honoured...

Dave Larrington - http://www.legslarry.beerdrinkers.co.uk/
===========================================================
Editor - British Human Power Club Newsletter
http://www.bhpc.org.uk/
===========================================================

 

[Dave Larrington]

Simon Brooke wrote:

> Yes, I looked too. Amazing looking frames. Amazing looking prices. Nucleon FR 2004 (including
> Rohloff) 3599 euros; Nucleon ST 2004 (including Rohloff) 3899 euros. Couldn't find any weights
> quoted, but they're all described as 'downhill', 'freeride' or 'enduro'. 'Downhill' and 'freeride'
> spell 'heavy' in my prejudiced mind.

www.nucleon.net sez "16-19kg (35-40lbs) for a complete bike"

Dave Larrington - http://www.legslarry.beerdrinkers.co.uk/
===========================================================
Editor - British Human Power Club Newsletter
http://www.bhpc.org.uk/
===========================================================

 

[David Nutter]

Peter Clinch <[email protected]> said:

> My experience of both Rohloff and Schlumpf is on the same bike! Darth Ben's "Ultimate Commuter",
> at Kinetics.

*looks*

Wow...shiny toy! Must have shiny toy!

I wonder who commissioned it?

Regards,

-david

 

[Simon Brooke]

"Dave Larrington" <[email protected]> writes:

> Simon Brooke wrote:
>
> > Yes, I looked too. Amazing looking frames. Amazing looking prices. Nucleon FR 2004 (including
> > Rohloff) 3599 euros; Nucleon ST 2004 (including Rohloff) 3899 euros. Couldn't find any weights
> > quoted, but they're all described as 'downhill', 'freeride' or 'enduro'. 'Downhill' and
> > 'freeride' spell 'heavy' in my prejudiced mind.
>
> www.nucleon.net sez "16-19kg (35-40lbs) for a complete bike"

Jings! OK, I do _not_ want one. Who wants to heave _that_ much ironmongery up a hill?

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/ ;; "If I were a Microsoft
Public Relations person, I would probably ;; be sobbing on a desk right now" -- Rob Miller,
editor, /.

 

[Tony Raven]

Simon Brooke wrote:
>
> Jings! OK, I do _not_ want one. Who wants to heave _that_ much ironmongery up a hill?

Its not designed for heaving up a hill any more than a Colnago is designed for bombing a rocky
downhill course.

Tony

--
"If you tell the truth you don't have to remember anything." Mark Twain

 

[Ouch]

<snip snip>

>Jings! OK, I do _not_ want one. Who wants to heave _that_ much ironmongery up a hill?

I do! That wouldn't be much heavier (if at all) than my current mtb.

That said, I'm also only into general XC with the occasional downhill (but not proper DHing) so the
lighter the better.

If you had the cash, it would be a nice display piece. People would point fingers and say 'wow'. I
think it's probably as much fun engineering as functional bike. I'd be proud to build something
like that.

 

[Simon Brooke]

"Tony Raven" <[email protected]> writes:

> Simon Brooke wrote:
> >
> > Jings! OK, I do _not_ want one. Who wants to heave _that_ much ironmongery up a hill?
>
> Its not designed for heaving up a hill any more than a Colnago is designed for bombing a rocky
> downhill course.

No, fair enough. But a cross-coutry variant of the Rohloff-at-the- suspension-pivot idea, weighing
in at about ten pounds less, would be my idea of a seriously nice bike. And it looks as if they have
the ability to build it... but it would still be beyond what I could afford.

The idea of using motors of one sort or another to get you up to the top of a hill so that you can
coast down doesn't quite fit my idea of cycling - it's motor cycling, except that the motor isn't
actually atacched to the bike.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/ ;; "If I were a Microsoft
Public Relations person, I would probably ;; be sobbing on a desk right now" -- Rob Miller,
editor, /.

 

[Tony Raven]

Simon Brooke wrote:
>
> The idea of using motors of one sort or another to get you up to the top of a hill so that you can
> coast down doesn't quite fit my idea of cycling - it's motor cycling, except that the motor isn't
> actually atacched to the bike.

I must admit to enjoying motor skiing as you would call it aka downhill skiing ;-)

Tony

--
"If you tell the truth you don't have to remember anything." Mark Twain

 

[Andrew Sweetman]

From: <ouch>
> I've read once that first generation mtbs used to be fitted
with drum
> brakes that had to be readjusted (or something) before every DH because they heated up so much. On
> that note I'd hope that
roller
> brakes are much better.
>

This was using old "cruiser" bikes before MTBs were developed. Racing down big hills on 50lb bikes
put so much heat into the hubs that the bearing grease ran out. Hence the "Repak" race - re-packing
the bearings with grease after the race. It's a function of the amount of braking more than the type
of brake really - rim brakes can heat the air in the tubes enough to blow the tyre off, disc brakes
can end up with warped discs, or I've even heard reports of the plastic brake hose melting off the
caliper. Generally drum brakes handle the heat from excessive braking better than anything else.

Having said all that, it's normally only a worry for tandems in Alpine terrain

Andrew

 

[Anonymous]

"Andrew Sweetman" <[email protected]> wrote in message
news:[email protected]...
> Generally drum brakes handle the heat from excessive braking better than anything else.
>
> Having said all that, it's normally only a worry for tandems in Alpine terrain

You should have seen how hot the brakes were after descending into Dent from Barbondale. Drum brake
on all the way down, and even then the rims were too hot to touch. The drum was well over 100 deg C
- water squirted onto it boiled instantly.

(thinks - about 200kg, 150m descent. PE = 200*10*150 = 300KJ. Descent time about 90 seconds, so
that's 3kW! Wind resistance at that speed takes about .5 kw, so even taking some of the other wild
approximations into account, I reckon we could have been putting 1.5 to 2kW into those brakes. No
wonder they suffered!)

Anyway the point is that it isn't alpine that does it for us, it's steep slow hills. Alpine, you
just let the speed go up and brake for the hairpins - you lose loads more to wind resistance.

cheers, clive

 

[Peter B]

"Simon Brooke" <[email protected]> wrote in message
news:[email protected]...
> The idea of using motors of one sort or another to get you up to the top of a hill so that you can
> coast down doesn't quite fit my idea of cycling - it's motor cycling, except that the motor isn't
> actually atacched to the bike.

Nor mine but that's how modern day mtbing began, lugging a heavy Shwinn (spl?) uphill for the joy of
scaring yourself witless (insert rhyme of choice) descending. According to folklore.

Of course none of us rode "trackies" with cow-horns in the woods XX years ago and I didn't have a
mate who used to fit dual linkage front suspension forks, liberated from old mcycles, to said
trackies ;-) And here I am, XX years later doing the same but swapping loads of wonga for a
technically superior bicycle, and no, I don't think I'd want to pedal 44 pounds around again for
even more wonga!

Pete, the Not A Retro Grouch.

 

[Kit Wolf]

Ouch,

Did you ever try the hub gear idea?

Kit

ouch <> wrote in message news:<[email protected]>...
> I'm wondering if anyone has experience mounting an internal hub gear (Sturmey Archer-ish) onto a
> mountainbike?
>
> I'm thinking about building one and wondered what the pros and cons would be + whether it's worth
> the effort.
>
> My reasons for doing this would be:
> 1. Hopefully easier to maintain (and clean) an internal hub gear
> 2. Maybe longer lasting??
> 3. Hopefully better gear changes
> 4. Interested in trying something new
>
> Also, what would become of my chainring(s) and front mech? My guess would be that I would choose
> just one chainring with a suitable number of teeth?
>
> If there are serious "cons" I will abandon this idea.

 

[Simon@Nicolai U]

Simon Brooke <[email protected]> wrote in message
news:<[email protected]>...
> ouch <> writes: Yes, I looked too. Amazing looking frames. Amazing looking prices. Nucleon FR 2004
> (including Rohloff) 3599 euros; Nucleon ST 2004 (including Rohloff) 3899 euros. Couldn't find any
> weights quoted, but they're all described as 'downhill', 'freeride' or 'enduro'. 'Downhill' and
> 'freeride' spell 'heavy' in my prejudiced mind. And a complete bike is going to cost upsides of
> £3,000. But they do look interesting.

Nicolai cross country frames are all Rohloff compatible (they have a long non-driveside dropout) and
can be supplied with cable stops for conventional gearing, rohloff or both. The full suspension
bikes need a chain tensioner since the effective chainstay length changes slightly through the
suspension travel. The hardtail has sliding vertical dropouts - either way changing a puncture is no
more difficult than on any other bike and you are still using a QR. The 'clickbox' used on the disc
brake Rohloff means no messing with cables.

The sealing on a Rohloff is generally considered excellent and since the chainline is perfectly
straight the chain, ring and rear cog last for ages (and are both reversible.) MTBR long term
reports on the Rohloff are pretty good and the initial cost/long term savings sum seems to stack up.

Give us a call or drop us an email for more info and UK prices.

Simon www.nicolai-uk.com [email protected]

 

[Simon Brooke]

[email protected] (Simon@Nicolai Uk) writes:

> Simon Brooke <[email protected]> wrote in message
> news:<[email protected]>...
> > ouch <> writes: Yes, I looked too. Amazing looking frames. Amazing looking prices. Nucleon FR
> > 2004 (including Rohloff) 3599 euros; Nucleon ST 2004 (including Rohloff) 3899 euros. Couldn't
> > find any weights quoted, but they're all described as 'downhill', 'freeride' or 'enduro'.
> > 'Downhill' and 'freeride' spell 'heavy' in my prejudiced mind. And a complete bike is going to
> > cost upsides of £3,000. But they do look interesting.
>
> Nicolai cross country frames are all Rohloff compatible (they have a long non-driveside dropout)
> and can be supplied with cable stops for conventional gearing, rohloff or both. The full
> suspension bikes need a chain tensioner since the effective chainstay length changes slightly
> through the suspension travel.

Thanks for your reply.

I confess it was the Nucleon style Rohloff-at-the-suspension-pivot frames that interested me. It
seems a good engineering solution to get the weight away from the unsprung hub right into the middle
of the frame, and also you'll get less chain tension problems with the gearbox output sprocket so
close to the pivot.

However, although these are clearly ruthlessly efficient sausage eating bicycles, they look to have
more to do with the King Tiger school of teutonic engineering than the Hindenberg school... I mean
16Kg for a complete bike is about 50% heavier than a state-of-the-art cross-country full suspension
bike (yes, I see the Nonius, and I see it has Rohloff compatible drop-outs, but that still makes the
hub unsprung weight; and also you don't quote a weight for the Nonius, either for the frame or the
complete bike).

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

Morning had broken, and I found when I looked that we had run out of copper roove nails.

 

[Simon@Nicolai U]

Simon Brooke <[email protected]> wrote in message
> I confess it was the Nucleon style Rohloff-at-the-suspension-pivot frames that interested me. It
> seems a good engineering solution to get the weight away from the unsprung hub right into the
> middle of the frame, and also you'll get less chain tension problems with the gearbox output
> sprocket so close to the pivot.

Have a look at www.g-boxx.org for Karl's ideas for the future. The current nucleons have a chain
drive from the crank to the rohloff. G-boxx internalises the crank to gearbox drive (and in the case
of the Nucleon TFR puts the drive chain inside the rear stays - completely internalising the
drivetrain). This is not going to be light to start with and will start life on downhill bikes but
who knows how it will develop over time.

>(yes, I see the Nonius, and I see it has Rohloff compatible drop-outs, but that still makes the hub
>unsprung weight; and also you don't quote a weight for the Nonius, either for the frame or the
>complete bike).

Nicolai shave a few hundred grams off the normal additional weight of a Speedhub by eliminating the
need for the torsion arm but you're right that it's unsprung weight. We're going to play with
Rohloff's on various Nicolai full sus bikes to see how much difference it actually makes. A lot of
the drivetrain that you're removing was unsprung anyway (all of it on the URT bikes that were common
a few years ago) and the additional unsprung weight as a percentage of the total weight of bike and
rider must be pretty minimal.

All the Nicolai Full-sussers have a Rohloff compatible left dropout and can be supplied with Rohloff
cable stops. The lightest is the Saturn which comes in below 4lb for the frame (plus 200g or so for
the shock). The Nonius and Helius CC are a bit heavier but can both build into sub-25lb bikes.

Cheers

Simon

 

[Simon Brooke]

[email protected] (Simon@Nicolai Uk) writes:

> Simon Brooke <[email protected]> wrote in message
> > I confess it was the Nucleon style Rohloff-at-the-suspension-pivot frames that interested me. It
> > seems a good engineering solution to get the weight away from the unsprung hub right into the
> > middle of the frame, and also you'll get less chain tension problems with the gearbox output
> > sprocket so close to the pivot.
>
> Have a look at www.g-boxx.org for Karl's ideas for the future. The current nucleons have a chain
> drive from the crank to the rohloff. G-boxx internalises the crank to gearbox drive (and in the
> case of the Nucleon TFR puts the drive chain inside the rear stays - completely internalising the
> drivetrain). This is not going to be light to start with and will start life on downhill bikes but
> who knows how it will develop over time.

Ah! Now that looks to be exactly what I was looking for. Many thanks.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

'Victories are not solutions.' ;; John Hume, Northern Irish politician, on Radio Scotland
1/2/95 ;; Nobel Peace Prize laureate 1998; few have deserved it so much