Cassette / hub / derailleur compatibility?

Richard Corfield

I currently have a (very worn out) Shimano 8 speed system with (also
very worn out and stretched) SRAM chain, so intend to replace both. They
were replaced together a year or so ago.

The system was originally Nexave. Now it's the same hub but the cassette
is something still Shimano but with a narrower range than the original
Nexave. It seems to have worn out quite quickly this time. Chain-rings
are original.

How easily could I use something like an SRAM cassette, or a KMC or
Wipperman chain? And if so, which is better? I don't need wide range
as, with three chain-rings, I don't use the range I have. Closer is
together and narrower range is more useful. This will make the chain-rings
more useful. A couple of manufacturers, including Shimano, do 13 to 23
or similar.

Thanks

- Richard

--
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_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
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Señor Chris

Richard Corfield wrote:

> Chain-rings are original.

So they're probably worn out as well.

> It seems to have worn out quite quickly this time.

Probably because the chain rings are worn out...

Peter Pan

Richard Corfield wrote:
> I currently have a (very worn out) Shimano 8 speed system with (also
> very worn out and stretched) SRAM chain, so intend to replace both. They
> were replaced together a year or so ago.
>
> The system was originally Nexave. Now it's the same hub but the cassette
> is something still Shimano but with a narrower range than the original
> Nexave. It seems to have worn out quite quickly this time. Chain-rings
> are original.
>
> How easily could I use something like an SRAM cassette, or a KMC or
> Wipperman chain? And if so, which is better? I don't need wide range
> as, with three chain-rings, I don't use the range I have. Closer is
> together and narrower range is more useful. This will make the chain-rings
> more useful. A couple of manufacturers, including Shimano, do 13 to 23
> or similar.
>

You can use any of the makes you listed as long as you get the right
model (8 speed compatibility). Like most manufacturers, they make
products that range from absolute crap/cheap to good/lightweight/bling
etc... Pick a brand and model which suits your budget, but if you cycle
a lot, forget the bottom of the range.
As Chris pointed out, the chainrings are likely worn as a year doesn't
sound a lot unless you are racking up loads of miles/year (> 3K at a
guess) or you are not cleaning/lubricating/checking for chain wear
sufficiently.
As I found out, regular (reliable) cycling does require maintenance and
expense :-)

Richard Corfield

On 2008-05-24, Señor Chris <nospam@ntlworld.com> wrote:
> Richard Corfield wrote:
>
>> Chain-rings are original.
>
> So they're probably worn out as well.
>
>> It seems to have worn out quite quickly this time.
>
> Probably because the chain rings are worn out...

Middle one mostly, which I could replace - or look at the cost of
replacing the whole set.

Still, how much do the hubs vary? Or stick with Shimano as that's the
rest of the equipment.

Thanks

- Richard

--
_/_/_/ _/_/_/ _/_/_/ Richard dot Corfield at gmail dot com
_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
_/ _/ _/_/ _/_/_/ except in the Twilight Zone

Richard Corfield

On 2008-05-24, Peter Pan <peter.pan@invalid.mail.kom> wrote:
>
> You can use any of the makes you listed as long as you get the right
> model (8 speed compatibility). Like most manufacturers, they make
> products that range from absolute crap/cheap to good/lightweight/bling
> etc... Pick a brand and model which suits your budget, but if you cycle
> a lot, forget the bottom of the range.
> As Chris pointed out, the chainrings are likely worn as a year doesn't
> sound a lot unless you are racking up loads of miles/year (> 3K at a
> guess) or you are not cleaning/lubricating/checking for chain wear
> sufficiently.
> As I found out, regular (reliable) cycling does require maintenance and
> expense :-)

I worked it out as a guestimate after posting that. Probably about 2K
for work travel (10 miles times 200 days average worker works), minus a
little for the odd car day or tandem day, plus a bit for leisure riding.
It goes through tyres and brake blocks quite well too, especially brake
blocks which means one day rims at which point cost of repair may be
more than cost of replace.

So are the splines and threads on the rear hub standard? Also a relatively
small set of hole spacings to choose from for the chain rings? Or best
going into a good bike shop and showing them what I want to replace? I
think the latter is starting to sound like a good idea.

Thanks

- Richard

--
_/_/_/ _/_/_/ _/_/_/ Richard dot Corfield at gmail dot com
_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
_/ _/ _/_/ _/_/_/ except in the Twilight Zone

Peter Pan

> I worked it out as a guestimate after posting that. Probably about 2K
> for work travel (10 miles times 200 days average worker works), minus a
> little for the odd car day or tandem day, plus a bit for leisure riding.
> It goes through tyres and brake blocks quite well too, especially brake
> blocks which means one day rims at which point cost of repair may be
> more than cost of replace.

You can probably reduce the number of brake pads you go through by
getting some wet-weather pads. Generic/Shimano ones tend to dissolve in
wet weather. Most people here would recommend Kool-Stop.


> So are the splines and threads on the rear hub standard?

The spacing between cogs is standard depending on the number of speeds
(7&8/9/10). Since you said 'cassette' earlier, a cassette is held on by
a lockring vs. a 'freewheel' which screws on to the rear hub. You need
to find out which one you bike has. Check sheldonbrown.com for a better
description.

> Also a relatively
> small set of hole spacings to choose from for the chain rings?

This depends on the number of bolts (4 or 5), there are various
standards/sizes. If you can find the model number, the manufacturer will
probably list the Bolt Circle Diameter (BCD) and you will need to
purchase chainrings of the same size (number of teeth and BCD). Common
Shimano 4 arm chainrings are usually "104/64" BCD, referring to the
outer&middle/inner chainring BCD's.


> Or best
> going into a good bike shop and showing them what I want to replace? I
> think the latter is starting to sound like a good idea.

Up to you, if you have the tools and the time, more fun doing it
yourself :-)

Richard Corfield

On 2008-05-25, Peter Pan <peter.pan@invalid.mail.kom> wrote:
>
> You can probably reduce the number of brake pads you go through by
> getting some wet-weather pads. Generic/Shimano ones tend to dissolve in
> wet weather. Most people here would recommend Kool-Stop.

Ok thanks. I've just replaced them with generic, so will have to try to
remember that for next time, or buy them now as I know I will end up
using them.

We get a lot of salt on the roads up here which probably didn't help the
chain either.

>> So are the splines and threads on the rear hub standard?
>
> The spacing between cogs is standard depending on the number of speeds
> (7&8/9/10). Since you said 'cassette' earlier, a cassette is held on by
> a lockring vs. a 'freewheel' which screws on to the rear hub. You need
> to find out which one you bike has. Check sheldonbrown.com for a better
> description.

The cassette is splined and slips over the hub, with the last cog
separate. A locking ring is then screwed in with a special tool. I'll
see if I can get to a cycle shop this weekend.

>> Also a relatively
>> small set of hole spacings to choose from for the chain rings?
>
> This depends on the number of bolts (4 or 5), there are various
> standards/sizes. If you can find the model number, the manufacturer will
> probably list the Bolt Circle Diameter (BCD) and you will need to
> purchase chainrings of the same size (number of teeth and BCD). Common
> Shimano 4 arm chainrings are usually "104/64" BCD, referring to the
> outer&middle/inner chainring BCD's.

OK thanks. It is a 4. 104/64 looks about right putting a steel rule
against it.

> Up to you, if you have the tools and the time, more fun doing it
> yourself :-)

I'd do it myself - it's just being able to see and talk about the parts
rather than ordering online.

- Richard

--
_/_/_/ _/_/_/ _/_/_/ Richard dot Corfield at gmail dot com
_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
_/ _/ _/_/ _/_/_/ except in the Twilight Zone