Shimano Freehub replacement dilemma

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Colin Stanley
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Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Shimano Freehub replacement dilemma

Postby Colin Stanley » 13 Feb 2019, 10:15am

Dear all,
Can someone please help me?
I am endeavouring to source a replacement Shimano freehub for a 9 speed cassette on a friend’s tandem. The freehub part that secures to the wheel hub by the tubular 10mm Alan bolt has sadly fractured.
Unfortunately, the tandem hub is a specially made one, machined to accept an Aria drag brake and a Shimano freehub, and has no ID number on it.
The photo shows it half stripped down on the wheel and just the outer part of the freehub on the kitchen work surface.
Image4.jpg

As there are many Shimano freehubs on the market, and I don’t know the part number, do I just go for one that takes a 9 speed cassette and looks like the outside end with that pressed steel cover plate with the ball race just behind it?
I take it that the position of the ball race will vary with whatever freehub is selected, although the RH cone should have a bit of leeway in lateral adjustment adding or subtracting spacers/washer to maintain the original OLN dimension?
Any suggestions please?

hamster
Posts: 3011
Joined: 2 Feb 2007, 12:42pm

Re: Shimano Freehub replacement dilemma

Postby hamster » 13 Feb 2019, 10:29am

Usually the differences appear to be in the dust seal design and diameters.
I'd be tempted to buy a Deore MTB hub and cannibalise it for the cones, dust seals and freehub. That way everything fits and you can service the bearings while you are at it.

Samuel D
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Joined: 8 Mar 2015, 11:05pm
Location: Paris

Re: Shimano Freehub replacement dilemma

Postby Samuel D » 13 Feb 2019, 10:42am

What does the other side (inner side) of the removed freehub body look like? The interface with the hub body differs on Shimano freehubs. This is the first thing you need to get right to have a hope of compatibility.

Colin Stanley
Posts: 315
Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Re: Shimano Freehub replacement dilemma

Postby Colin Stanley » 13 Feb 2019, 10:44am

Hi, so you are suggesting that a Deore freehub might possibly fit the tandem wheel hub?
I take it that the 10mm tubular bolt and driving spline interfaces are common?

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Shimano Freehub replacement dilemma

Postby Brucey » 13 Feb 2019, 10:45am

there are dozens of shimano freehub bodies that look about the same. The good news is that a lot of them can be made to do the same job too, provided the interface to the hubshell is the same. Design variations include;

a) hubshell interface (spline style)
b) washer at hubshell interface
c) bolt diameter (goes with axle diameter)
d) body length (4s,5s,6s,7s, 8/9/10s, 11s, etc)
e) body offset
f) body spline style (UG, HG, solid or ribbed spline)
g) number and type of pawls inside
h) LH seal type
i) RH dustcap type.

The good news is that many of these things usually go together, so for example if the spline length is correct, it is odds-on that the offset will be too. I'd be reasonably confident that you will be able to get a freehub body that will fit OK, even if you have to replace the dustcap.

The failure that has occurred is not that unusual and may have been helped along by one of three things
1) hollow bolt not tight enough
2) freehub bearings too loose
3) main hub bearings too tight (they need to be set with a little slack that just disappears as the QR is tightened)

The correct (tandem rated) part for shimano tandem hubs is Y3A5-98070 (listed by SJS but not in stock at present), fits FH-HF08, and looks identical to your freehub body. I am told that this (uniquely amongst shimano freehub bodies of this type) has three pawls inside, not two, but I've never taken one to bits to find out for sure.

The hub you have looks like FH-HF08 to me; could the original markings have been polished off or something?

http://www.sjscycles.com/Drawings/Shimano/Shimano_FH-HF08_Tech_Doc.pdf

Image

hth

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Colin Stanley
Posts: 315
Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Re: Shimano Freehub replacement dilemma

Postby Colin Stanley » 13 Feb 2019, 11:00am

Thank you folks for your inputs, esp Brucey, your are like a walking encyclopedia
Image7.jpg

what is left of the freehub inner part. It had two pawls and a lot of debris...
Clearly a different driving spline would be problematic.
A small adjustment in cone placing could be overcome.

Colin Stanley
Posts: 315
Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Re: Shimano Freehub replacement dilemma

Postby Colin Stanley » 13 Feb 2019, 11:14am

so how many hubshell interface (spline style) types are there please?

Brucey
Posts: 32690
Joined: 4 Jan 2012, 6:25pm

Re: Shimano Freehub replacement dilemma

Postby Brucey » 13 Feb 2019, 1:20pm

Colin Stanley wrote:so how many hubshell interface (spline style) types are there please?


lots but yours is the most common and I think lots of freehub bodies will fit and work.

this page

https://www.cykelpartner.dk/kassettehus-shimano-deore-xt-8-gear-fh-hf08_Y3A598070.html

has a photo from the reverse direction and says FH-HF08 freehub body is also an XT part number, which rather suggests that it is a two-pawl freehub body. It seems to have a seal on the LH side. I think a 9s deore , LX or XT freehub body could work, esp if you are prepared to change the RH dustcap. FWIW I think this one will fit

https://www.sjscycles.co.uk/hub-spares/shimano-deore-fhm525sl-cassette-freehub-body-y3sp98060/

but can't be 100% sure without trying it.

BTW if there was debris inside the freehub body it is somewhat chicken and eggish; a combination of debris and no clearance in the bearings would result in huge loads on the part that broke off the end of the inner part of the freehub body, so it is difficult to say what happened first.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

rjb
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Location: Somerset (originally 60/70's Plymouth)

Re: Shimano Freehub replacement dilemma

Postby rjb » 13 Feb 2019, 1:43pm

The hub looks similar to the Quando hubs fitted to Dawes Tandems. Mine was marked with quando on the nds bearing cover. It had 10x 7/32 balls on the drive side and 9 x1/4 balls on the nds. Link here to it from another thread. viewtopic.php?f=5&t=69984&p=1028105&hilit=Quando#p1028105 :wink:
At the last count:- Focus Variado, Peugeot 531 pro, Dawes Discovery Tandem, 2 Dawes Kingpins, Raleigh 20, Falcon K2 MTB dropped bar tourer, On One Pompino, Longstaff trike conversion on a Falcon corsa. :D

Brucey
Posts: 32690
Joined: 4 Jan 2012, 6:25pm

Re: Shimano Freehub replacement dilemma

Postby Brucey » 13 Feb 2019, 1:47pm

quando freehubs do not use that interface onto the hubshell.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

reohn2
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Joined: 26 Jun 2009, 8:21pm

Re: Shimano Freehub replacement dilemma

Postby reohn2 » 13 Feb 2019, 4:16pm

If I were the OP I'd buy a complete Deore M525 hub for not much more than the free hub body:- https://www.wiggle.co.uk/shimano-deore- ... bXEALw_wcB
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I cycle therefore I am.

Colin Stanley
Posts: 315
Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Re: Shimano Freehub replacement dilemma

Postby Colin Stanley » 13 Feb 2019, 6:35pm

My thanks to you all. Some really great advice.

Colin Stanley
Posts: 315
Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Re: Shimano Freehub replacement dilemma

Postby Colin Stanley » 21 Feb 2019, 5:50pm

It's me again. Thanks for all the advice.
Fitted a new Deore 9 speed FH M525 freehub but had to have it shimmed out from the wheel hub to prevent the outer casing (where the cassette sits) from binding. Reassembled the axle, cones and ball bearings and find it impossible to adjust the wheel bearings as they are tight and then loose as the axle is rotated by hand. Possibly a bent axle, or the free hub not sitting square ?
The axle is 155mm wide (long ?). I take it this is longer than for a solo bike ??
Any ideas on where I might buy a Shimano rear hollow axle of this dimension please ?


Colin Stanley
Posts: 315
Joined: 12 May 2007, 7:05pm
Location: Somewhere in Kent

Re: Shimano Freehub replacement dilemma

Postby Colin Stanley » 21 Feb 2019, 9:09pm

Indeed, that looks tandem size. Thank you.