internal to external gears

Peter

Hi

I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
internal gear hub (called a "Nexus SG-7R46).

The gear hub has recently become very "sloppy" and now is basically
unusable. The local bicycle mechanic has told me it would cost about
170 to 200 Euros to replace.

Before I accept this offer, I was just wondering if it is possible (in
general) to change a bike from using an internal gear hub to using
external gears? Obviously the rear wheel would either need to be
replaces, or at least fitted with a new axel and spokes.... or what?


Thanks,
Peter

landotter

On May 13, 3:06 pm, "Peter" <xdz...@hotmail.com> wrote:
> Hi
>
> I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> internal gear hub (called a "Nexus SG-7R46).
>
> The gear hub has recently become very "sloppy" and now is basically
> unusable. The local bicycle mechanic has told me it would cost about
> 170 to 200 Euros to replace.
>
> Before I accept this offer, I was just wondering if it is possible (in
> general) to change a bike from using an internal gear hub to using
> external gears?

Possible? Yes. Practical? No. If you're in the part of the world where
700c 3/5/7/8 Nexus replacement wheels are common, then this is the
best option--if the part needs to be replaced.

Has the obvious been checked? Is there bearing play? Is the shifter
worn? Is the cable adjusted properly? It could be a cheap fix--but
seven years on a well used city bike could very well mean that it's
time for a fresh hub.

Peter

landotter wrote:

> On May 13, 3:06 pm, "Peter" <xdz...@hotmail.com> wrote:
> > Hi
> >
> > I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> > internal gear hub (called a "Nexus SG-7R46).
> >
> > The gear hub has recently become very "sloppy" and now is basically
> > unusable. The local bicycle mechanic has told me it would cost about
> > 170 to 200 Euros to replace.
> >
> > Before I accept this offer, I was just wondering if it is possible
> > (in general) to change a bike from using an internal gear hub to
> > using external gears?
>
> Possible? Yes. Practical? No. If you're in the part of the world where
> 700c 3/5/7/8 Nexus replacement wheels are common, then this is the
> best option--if the part needs to be replaced.
>
> Has the obvious been checked? Is there bearing play? Is the shifter
> worn? Is the cable adjusted properly? It could be a cheap fix--but
> seven years on a well used city bike could very well mean that it's
> time for a fresh hub.

Thanks for your comments. The bike mechanic said the hub was shot, not
that he opened it to look at what exactly was wrong. It would be
cheaper to replace the whole hub than to try to fix it.

The entire real wheel rocks about 1 to 2 cm from side to side, so I
guess something is pretty broken.

/Peter

Andre Jute

On May 13, 9:06*pm, "Peter" <xdz...@hotmail.com> wrote:
> Hi
>
> I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> internal gear hub (called a "Nexus SG-7R46).
>
> The gear hub has recently become very "sloppy" and now is basically
> unusable. The local bicycle mechanic has told me it would cost about
> 170 to 200 Euros to replace.

It might be rebuildable (probably expensive) or you could just buy an
entire new wheel with a new Nexus 7 speed already fitted. It might be
smart to buy an appropriate so-called "fitting kit" at the same time,
depending on how battered the anti-turn washers are.

There are some wheels with Nexus hubs here:
http://sport.search.ebay.de/nexus_F...40QQsacatZ22688
and it looks like you should be able to get a 7 speed gear hub wheel
for around 100 Euro plus postage. The 8 speed Nexus goes for around
120-130 Euro now on Ebay, but to use that you would need the
appropriate fitting kit, possibly a rollerbrake (unless you have rim
brakes), and a gearchange controller (similar to the most likely
rotary control for the 7 speed you have now but for 8 speeds). If you
have a coaster brake on your 7 speed Nexus hub, you should probably
avoid expense and fitting difficulties for another brake by buying
another coaster brake hub.

If you go look on the Paul Lange site you will find exploded drawings
for the Shimano parts which will show you how the parts relate.

> Before I accept this offer, I was just wondering if it is possible (in
> general) to change a bike from using an internal gear hub to using
> external gears? Obviously the rear wheel would either need to be
> replaces, or at least fitted with a new axel and spokes.... or what?

It depends on the frame. If it was custom-made to fit the internal
gears, there is usually nowhere to hang the derailleurs and chain
tensioner.

HTH.

Andre Jute
http://members.lycos.co.uk/fiultra/...%20CYCLING.html

Andre Jute

On May 13, 9:30*pm, "Peter" <xdz...@hotmail.com> wrote:
> landotter wrote:
> > On May 13, 3:06 pm, "Peter" <xdz...@hotmail.com> wrote:
> > > Hi
>
> > > I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> > > internal gear hub (called a "Nexus SG-7R46).
>
> > > The gear hub has recently become very "sloppy" and now is basically
> > > unusable. The local bicycle mechanic has told me it would cost about
> > > 170 to 200 Euros to replace.
>
> > > Before I accept this offer, I was just wondering if it is possible
> > > (in general) to change a bike from using an internal gear hub to
> > > using external gears?
>
> > Possible? Yes. Practical? No. If you're in the part of the world where
> > 700c 3/5/7/8 Nexus replacement wheels are common, then this is the
> > best option--if the part needs to be replaced.
>
> > Has the obvious been checked? Is there bearing play? Is the shifter
> > worn? Is the cable adjusted properly? It could be a cheap fix--but
> > seven years on a well used city bike could very well mean that it's
> > time for a fresh hub.
>
> Thanks for your comments. The bike mechanic said the hub was shot, not
> that he opened it to look at what exactly was wrong. It would be
> cheaper to replace the whole hub than to try to fix it.
>
> The entire real wheel rocks about 1 to 2 cm from side to side, so I
> guess something is pretty broken.

That might just mean the axle is loose in the track ends. Get the
fitting and maintenance instructions from the Paul Lange site and just
check for a start that everything is bolted up correctly, and then
follow the instructions for adjusting the gearbox -- it is a lot
easier than you might think, and you can do it without any tools.

Andre Jute

phs123@gmail.com

Peter skrev:

> I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> internal gear hub (called a "Nexus SG-7R46).
>
> The gear hub has recently become very "sloppy" and now is basically
> unusable. The local bicycle mechanic has told me it would cost about
> 170 to 200 Euros to replace.
>
> Before I accept this offer, I was just wondering if it is possible (in
> general) to change a bike from using an internal gear hub to using
> external gears? Obviously the rear wheel would either need to be
> replaces, or at least fitted with a new axel and spokes.... or what?

Appearently on can add the device below on bikes without gear drop
out:
http://www.roseversand.de/output/co...10&detail2=1807

So if you could live with only 8-10 gears* you could perhaps get away
with such a device, one new rear shifter. Eg. Sram Shimano compatible
"Attack" shifters are sold individually, a new derailleur, cables,
chain, cassette and rear wheel. A Deda "Dog Fang" and a bash guard
would be nice too, so as to avoid chain drops.
* The gear spread would be closer though than on the Nexus hub.

Not sure if it is a much cheaper option even if you do it yourself.

Do check if the axel is broken. I vaguely remember that roll brake
hubs can snap axels if the "contra torque" arm wasn't attached when
braking.
Also check the races in the bearings. I do believe that the races
aren't replaceable on the Nexus hubs, so if the races are shot, then
so are the hub.

Converting it to a singlespeed is perhaps the cheapest thing to do.


--
Regards

Tosspot

Peter wrote:
> Hi
>
> I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> internal gear hub (called a "Nexus SG-7R46).
>
> The gear hub has recently become very "sloppy" and now is basically
> unusable. The local bicycle mechanic has told me it would cost about
> 170 to 200 Euros to replace.

This sounds like far too much money to me. I'd seek a second opinion.
I can't find any links but a replacement hub can't be much over a
hundred, and in my experience, that's the same cost a new wheel.

> Before I accept this offer, I was just wondering if it is possible (in
> general) to change a bike from using an internal gear hub to using
> external gears? Obviously the rear wheel would either need to be
> replaces, or at least fitted with a new axel and spokes.... or what?

I wouldn't, you'd need cables, shifters, new wheel, cassette, hanger, it
wouldn't be the cheap option, brake levers might be an issue as well.

Peter

Tosspot wrote:

> Peter wrote:
> > I have an approx 7 year old bike (a Nishiki 407 hybrid) which has an
> > internal gear hub (called a "Nexus SG-7R46).
> >
> > The gear hub has recently become very "sloppy" and now is basically
> > unusable. The local bicycle mechanic has told me it would cost about
> > 170 to 200 Euros to replace.
>
> This sounds like far too much money to me. I'd seek a second
> opinion. I can't find any links but a replacement hub can't be much
> over a hundred, and in my experience, that's the same cost a new
> wheel.

Actually this was 2 opinions. One guy told me it would cost about 170,
another about 200. 75% of the cost was the actual gear hub - the work
was about 25% of the total price.


> > Before I accept this offer, I was just wondering if it is possible
> > (in general) to change a bike from using an internal gear hub to
> > using external gears? Obviously the rear wheel would either need to
> > be replaces, or at least fitted with a new axel and spokes.... or
> > what?
>
> I wouldn't, you'd need cables, shifters, new wheel, cassette, hanger,
> it wouldn't be the cheap option, brake levers might be an issue as
> well.

Yes - it does seem it is not easily possible. Unfortunately I have
never really been completely satisfied with the internal gears -
doesn't really seem to have the same "range" as an external system, and
I always found external gears easy to adjust and maintain. Not that
there has been much maintanence really with the internal hub, just that
when something does need to be done it seems a lot harder.


Thanks,
Peter

Peter

Andre Jute wrote:

> On May 13, 9:30*pm, "Peter" <xdz...@hotmail.com> wrote:
> > landotter wrote:
> > > On May 13, 3:06 pm, "Peter" <xdz...@hotmail.com> wrote:
> > > > Hi
> >
> > > > I have an approx 7 year old bike (a Nishiki 407 hybrid) which
> > > > has an internal gear hub (called a "Nexus SG-7R46).
> >
> > > > The gear hub has recently become very "sloppy" and now is
> > > > basically unusable. The local bicycle mechanic has told me it
> > > > would cost about 170 to 200 Euros to replace.
> >
> > > > Before I accept this offer, I was just wondering if it is
> > > > possible (in general) to change a bike from using an internal
> > > > gear hub to using external gears?
> >
> > > Possible? Yes. Practical? No. If you're in the part of the world
> > > where 700c 3/5/7/8 Nexus replacement wheels are common, then this
> > > is the best option--if the part needs to be replaced.
> >
> > > Has the obvious been checked? Is there bearing play? Is the
> > > shifter worn? Is the cable adjusted properly? It could be a cheap
> > > fix--but seven years on a well used city bike could very well
> > > mean that it's time for a fresh hub.
> >
> > Thanks for your comments. The bike mechanic said the hub was shot,
> > not that he opened it to look at what exactly was wrong. It would be
> > cheaper to replace the whole hub than to try to fix it.
> >
> > The entire real wheel rocks about 1 to 2 cm from side to side, so I
> > guess something is pretty broken.
>
> That might just mean the axle is loose in the track ends. Get the
> fitting and maintenance instructions from the Paul Lange site and just
> check for a start that everything is bolted up correctly, and then
> follow the instructions for adjusting the gearbox -- it is a lot
> easier than you might think, and you can do it without any tools.

Hi - thanks for the tip. Do you have the url to that website?

/Peter

Ted Mittelstaedt

"Peter" <xdzgor@hotmail.com> wrote in message
news:482a940d$0$15885$edfadb0f@dtext01.news.tele.dk...
> Andre Jute wrote:
>
> > On May 13, 9:30 pm, "Peter" <xdz...@hotmail.com> wrote:
> > > landotter wrote:
> > > > On May 13, 3:06 pm, "Peter" <xdz...@hotmail.com> wrote:
> > > > > Hi
> > >
> > > > > I have an approx 7 year old bike (a Nishiki 407 hybrid) which
> > > > > has an internal gear hub (called a "Nexus SG-7R46).
> > >
> > > > > The gear hub has recently become very "sloppy" and now is
> > > > > basically unusable. The local bicycle mechanic has told me it
> > > > > would cost about 170 to 200 Euros to replace.
> > >
> > > > > Before I accept this offer, I was just wondering if it is
> > > > > possible (in general) to change a bike from using an internal
> > > > > gear hub to using external gears?
> > >
> > > > Possible? Yes. Practical? No. If you're in the part of the world
> > > > where 700c 3/5/7/8 Nexus replacement wheels are common, then this
> > > > is the best option--if the part needs to be replaced.
> > >
> > > > Has the obvious been checked? Is there bearing play? Is the
> > > > shifter worn? Is the cable adjusted properly? It could be a cheap
> > > > fix--but seven years on a well used city bike could very well
> > > > mean that it's time for a fresh hub.
> > >
> > > Thanks for your comments. The bike mechanic said the hub was shot,
> > > not that he opened it to look at what exactly was wrong. It would be
> > > cheaper to replace the whole hub than to try to fix it.
> > >
> > > The entire real wheel rocks about 1 to 2 cm from side to side, so I
> > > guess something is pretty broken.
> >
> > That might just mean the axle is loose in the track ends. Get the
> > fitting and maintenance instructions from the Paul Lange site and just
> > check for a start that everything is bolted up correctly, and then
> > follow the instructions for adjusting the gearbox -- it is a lot
> > easier than you might think, and you can do it without any tools.
>
> Hi - thanks for the tip. Do you have the url to that website?
>
> /Peter

Hi Peter,

Hold on there a bit. This is classic bearing failure. But so what - as
long as you can spin the wheel and you do not hear or feel metal
grinding on metal, the races are probably fine. In any case until
someone actually looks at the bearings, your "mekanics" are just blowing
air out their asses.

If you go here:

http://cycle.shimano-eu.com/publish...al_service.html

click Technical Documents, you get

http://techdocs.shimano.com/techdocs/index.jsp

put the cursor over Comfort and find your hub, then download it. You will
get an exploded drawing. Here is the URL for one for example:
http://techdocs.shimano.com/media/t...69830615762.pdf

When I looked at it I thought Sheesh how simple, I was taking apart and
fixing stuff like this when I was 15 years old.

If the bike mechanic you are using doesen't want to touch it (sounds like it
to me)
then find another one or take it apart yourself. Why not - if your
convinced that
the hub is shot and your going to replace it, then take the thing apart so
you can
see how it works - what are you going to do, break it? It's a learning
experience.

I doubt the race is shot, I suspect more likely that the ball retainer
inside the bearing
is damaged and 1 or more bearings have fallen out. That part can be tossed
and
new and more bearings added. Most of the time ball bearing retainers are
for pussies
anyway, all they do is make it easy for someone on an assembly line to slap
together
bearings a mile a minute.

A mechanic that makes a "replace it with a new part your part is shot"
diagnosis
without even taking it apart, simply is either a tremendous lazy-ass, or
incompetent,
or just has a lot of work already lined up that he can do in his sleep,
since he's
done it over and over and over again. None of which you want to reward by
tossing them money for taking a part out of a box and replacing it on your
bike.

These hubs are designed to be taken apart and rebuilt. Parts are available.
Just
because the locals you have talked to are too unimaginative to e-mail a
credit card number
to a foreign distributor and get a part mailed to them doesen't mean that
it's not
possible to do it. Print out the exploded diagram, go back to your
mechanic,
and tell him to get off his butt and show you the "shot" bearing race.

Ted

Peter

Ted Mittelstaedt wrote:

> Hold on there a bit. This is classic bearing failure. But so what -
> as long as you can spin the wheel and you do not hear or feel metal
> grinding on metal, the races are probably fine. In any case until
> someone actually looks at the bearings, your "mekanics" are just
> blowing air out their asses.
>
> If you go here:
>
> http://cycle.shimano-eu.com/publish...l/en/technical_
> service.html
>
> click Technical Documents, you get
>
> http://techdocs.shimano.com/techdocs/index.jsp
>
> put the cursor over Comfort and find your hub, then download it. You
> will get an exploded drawing. Here is the URL for one for example:
> http://techdocs.shimano.com/media/t...e/EV/bikecompon
> ents/SG/EV-SG-7R46-2128C_v1_m56577569830615762.pdf
>
> When I looked at it I thought Sheesh how simple, I was taking apart
> and fixing stuff like this when I was 15 years old.
>
> If the bike mechanic you are using doesen't want to touch it (sounds
> like it to me)
> then find another one or take it apart yourself. Why not - if your
> convinced that
> the hub is shot and your going to replace it, then take the thing
> apart so you can
> see how it works - what are you going to do, break it? It's a
> learning experience.

Absolutely. I had come to the same conclusion myself. Instead of losing
the thing to the mechanic, I can remove it myself, and either try to
repair it or replace it with a new one. In any case, if I really can't
refit it (or a new one), I can take it to the bike mechanic like I was
going to do anyway.

Thanks for the links.

/Peter

cmcanulty

Get a copy of Glenn's Complete Bicycle Manual out of library (an old
book) has detailed exploded views of internal gear hubs. Won't be
exactly your hub but close enough. I redid a 3 speed hub once with
only the book and no knowledge, didn't even need any parts.

Andre Jute

Peter <xdzgor@hotmail.com> wrote:

> Andre Jute wrote:
>
> > On May 13, 9:30*pm, "Peter" <xdz...@hotmail.com> wrote:
> > > landotter wrote:
> > > > On May 13, 3:06 pm, "Peter" <xdz...@hotmail.com> wrote:
> > > > > Hi
> > >
> > > > > I have an approx 7 year old bike (a Nishiki 407 hybrid) which
> > > > > has an internal gear hub (called a "Nexus SG-7R46).
> > >
> > > > > The gear hub has recently become very "sloppy" and now is
> > > > > basically unusable. The local bicycle mechanic has told me it
> > > > > would cost about 170 to 200 Euros to replace.
> > >
> > > > > Before I accept this offer, I was just wondering if it is
> > > > > possible (in general) to change a bike from using an internal
> > > > > gear hub to using external gears?
> > >
> > > > Possible? Yes. Practical? No. If you're in the part of the world
> > > > where 700c 3/5/7/8 Nexus replacement wheels are common, then this
> > > > is the best option--if the part needs to be replaced.
> > >
> > > > Has the obvious been checked? Is there bearing play? Is the
> > > > shifter worn? Is the cable adjusted properly? It could be a cheap
> > > > fix--but seven years on a well used city bike could very well
> > > > mean that it's time for a fresh hub.
> > >
> > > Thanks for your comments. The bike mechanic said the hub was shot,
> > > not that he opened it to look at what exactly was wrong. It would be
> > > cheaper to replace the whole hub than to try to fix it.
> > >
> > > The entire real wheel rocks about 1 to 2 cm from side to side, so I
> > > guess something is pretty broken.
> >
> > That might just mean the axle is loose in the track ends. Get the
> > fitting and maintenance instructions from the Paul Lange site and just
> > check for a start that everything is bolted up correctly, and then
> > follow the instructions for adjusting the gearbox -- it is a lot
> > easier than you might think, and you can do it without any tools.
>
> Hi - thanks for the tip. Do you have the url to that website?
>
> /Peter

You could just go straight to Shimano -- this is your gearbox:
http://cycle.shimano-eu.com/catalog/cycle/products/group.jsp?JSESSIONID=LqtFytw1jXhdRMT8Yyvhyk17nLsPdDRcDKSVl92rlqvtYg2J4 FSk!-1783661778&FOLDER%3C%3Efolder_id=2534374302029743&PRODUCT%3C%3Eprd_id=845524441762959&ASSORTMENT%3C%3East_id=1408474395181175&CONTENT%3C%3Ecnt_id=10134198673243727&bmUID=1210772869827

Here's an alternative direct link to the tech docs for the Nexus Inter
7 gearbox and brake and shift controls:

http://techdocs.shimano.com/techdocs/blevel.jsp?JSESSIONID=LqtHfCR9J5PgmghfbFDqgL1XgdYRyxpmDlJhcnXHpyKBkkn3 jVkQ!703007568&FOLDER%3C%3Efolder_id=2534374302052227&ASSORTMENT%3C%3East_id=1408474395181679&bmUID=1210772871066

More parts via the "Comfort" tab to the left of the page.

Here is Paul Lange's Shimano site. He is, as far as I can make it, the
main German or possibly Continental distributor of Shimano gear. Since
his site is mainly aimed at bike shops, it has much more detailed info
than Shimano's own site, which is aimed at consumers.

http://www.paul-lange.de/produkte/shimano/

There is actually an English version somewhere but you'll have to find
it yourself; I just use the German version which anyhow gives you the
choice, IIRC, of downloading English datasheets (I long since
downloaded all the datasheets of all the Shimano components I have on
my bikes and keep them on my computer and printed out in a book of
plastic leaves I take to my LBS if the bike goes there). Go down to
"Support" and root around. Here are some further links you might visit
at Lange:

http://www.paul-lange.de/produkte/shimano/support/

http://www.paul-lange.de/produkte/shimano/komfort/

Somewhere on these huge compilations of pages, possibly on this one,

http://www.paul-lange.de/produkte/s...ionszeichnungen

is a detailed description of how to take apart, service and reassemble
a Nexus Inter-8 internal hub, so I assume that there is one for the
Inter-7 hub as well. If you can't find it, I'll be happy to send you
by e-mail (4.4Mb pdf) the version for the 8-speed hub I have on my own
computer. I cannot imagine that the disassembly method would be very
different between the 7 and 8 speed hubs.

One final note: it might be possible to order just the internal
assembly of the 7-speed hub, rather than buy a whole new wheel with a
new hub spoked in. The internal assembly has a part number and I've
seen it advertised.

HTH.

Andre Jute
http://members.lycos.co.uk/fiultra/...%20CYCLING.html

Ted Mittelstaedt

"cmcanulty" <cmcanulty@gmail.com> wrote in message
news:ba237a38-c794-4140-84e3-b8d169fa58ce@r66g2000hsg.googlegroups.com...
> Get a copy of Glenn's Complete Bicycle Manual out of library (an old
> book) has detailed exploded views of internal gear hubs. Won't be
> exactly your hub but close enough. I redid a 3 speed hub once with
> only the book and no knowledge, didn't even need any parts.

I thought that Sturmey Archer manufactured virtually all 3 speed hubs
for almost a half century, even the ones OEMed by other people.

Ted