Shimano Hub 7 to 9 speed - Can i just change the freehub?

Hi,

Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?

Regards,

Reader

Reader wrote:

Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?

And the rear mech. And the rear shifter. Apart from that, no problem.

8 speed might be easier, most 7 speed mechs will handle 8 speed.

--
Guy
===
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http://www.chapmancentral.co.uk

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"Just zis Guy, you know?" wrote in message
...
Reader wrote:

Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?

And the rear mech. And the rear shifter. Apart from that, no problem.

8 speed might be easier, most 7 speed mechs will handle 8 speed.


....and don't forget that the cones will be different, as will axle spacing.
You'll also therefore need to redish the wheel. The chain and cassette will
obviously both have to go, but I'm sure you'd anticipated this.


---
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In article , Simon D wrote:
"Just zis Guy, you know?" wrote in message
...
Reader wrote:

Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?

And the rear mech. And the rear shifter. Apart from that, no problem.
8 speed might be easier, most 7 speed mechs will handle 8 speed.

...and don't forget that the cones will be different, as will axle spacing.
You'll also therefore need to redish the wheel. The chain and cassette will
obviously both have to go, but I'm sure you'd anticipated this.

Or, from what I remember Sheldon saying, you can use 8 sprockets of a 9-speed
system on a 7-speed hub, without redishing the wheel or spreading the frame
(but it will need a new shifter and chain as much as a full move to 9 would).

Reader wrote:
Hi,

Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?

Regards,

Reader

Like one of the other replies implied 9 speed is wider than 7 so you will
probably have to respace the frame and redish the wheel. A good compromise
in my opinion is to use 8 sprockets and 7 spacers from a 9 speed cassette,
these will fit onto a 7 speed hyperglide cassette body and will not be
anywider than it was before so you don't need to respace the frame and
redish the wheel. You'll still need 9 speed shifters and chain and may need
a new rear mech. This is pretty much what I am going to do later this week,
actually my bike will be ugraded from 6 to 8 this way. It offers a good
upgrade path IMO, when I decide to get a new rear wheel, I will then respace
the frame and fit the ninth sprocket to get 9 speed. Sheldon Brown calls
this 8 of 9 on 7, look it up.

Just zis Guy, you know? wrote:
Reader wrote:


Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?


And the rear mech. And the rear shifter. Apart from that, no problem.

Not forgetting to have the frame re-spaced from 126mm to 130mm !
(not possible with aluminium frames, sadly, otherwise I might
try a 9 or 10-speed setup one day ...).

** Phil.

"Just Zis Guy" writes:
And the rear mech

That is absolutely unnecessary

And the rear shifter. Apart from that, no problem

The chain would also need to be replaced with a nine speed model. Th
right-hand cone and seal must match the freehub body. As the new freehu
body adds a few millimetres to the right hand side of the hub, it i
usually necessary to re-dish the wheel slightly, re-space the axle, an
sometimes to spread the frame

8 speed might be easier, most 7 speed mechs will handle 8 speed

Any derailleur that will handle eight speeds will also handle nine, a
eight speed cassette having the same overall width as a nine

One is not obliged to answer a question to which one does not kno
the answer

N. Lenderby (Mrs


-

Philip TAYLOR [PC87S/O-XP] wrote:

Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?

And the rear mech. And the rear shifter. Apart from that, no
problem.

Not forgetting to have the frame re-spaced from 126mm to 130mm !
(not possible with aluminium frames, sadly, otherwise I might
try a 9 or 10-speed setup one day ...).

Unless your frame is already 130 OLN or more, as every cassette-based system
I have seen has been (indeed none of our bikes is currently less than this,
although at least three were supplied with 7sp freehubs). I freely admit to
limited experience, though.

I reckon 8sp will just work, 9sp might be harder. But what do I know?

--
Guy
===
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

Victory is ours! Down with Eric the Half A Brain!

"Philip TAYLOR [PC87S/O-XP]" wrote in message
s.com...
Just zis Guy, you know? wrote:
Reader wrote:


Is it possible to upgrade from a 7speed cassette to a 9speed just by
changing the freehub? Or do i need to get a completely new hub?


And the rear mech. And the rear shifter. Apart from that, no problem.

Not forgetting to have the frame re-spaced from 126mm to 130mm !
(not possible with aluminium frames, sadly, otherwise I might
try a 9 or 10-speed setup one day ...).

And having re-spaced the frame, you'll have to adjust the size of the space
you use to park your bike in your garage, and if there isn't room you'll
just have to move house.

Apart from that, no problem :-^

Just zis Guy, you know? wrote:

Not forgetting to have the frame re-spaced from 126mm to 130mm !
(not possible with aluminium frames, sadly, otherwise I might
try a 9 or 10-speed setup one day ...).

Unless your frame is already 130 OLN or more, as every cassette-based
system I have seen has been (indeed none of our bikes is currently
less than this, although at least three were supplied with 7sp
freehubs). I freely admit to limited experience, though.

Maybe your 7sp experience is limited to "MTB"-style hubs.......

From http://www.sheldonbrown.com/frame-spacing.html :
120 mm Rear 5-speed, Ultra 6, newer track hubs.
126 mm Rear 6- and 7-speed (road).
130 mm Rear 7-speed (MTB) and 8- 9- and 10-speed (road).
135 mm Rear 7- 8- and 9-speed (MTB)

"8 Of 9 On 7" :
http://www.sheldonbrown.com/k7.html#up7

~PB