Buying new wheels, confused over freehubs.

[grognut]

Hi,

This has probably been covered before but after doing a search on the forum and looking through many pages of results I decide to ask the questions directly.

I have a 35 year old bike and I'm still using the original Normandy high flange wheels. The cones are ruined and the cups are somewhat pitted. I have replaced the cones with some shimano ones a few years back. They were a close fit but not correct and the balls ride on the edge so eventually the cones get ruined which probably means the cups will degrade quicker. I've just replaced them again but they won't last.

So I've decided to buy some new wheels.

I'm thinking of the SPA tiagra or 105 because the OLN is 130mm and I can probably get the 120mm frame out to this. (steel).

I'm currently running a triple at the front and a 7-speed at the back and, although I find the 7-speed OK, I don't want to limit myself to 7 but have the chance to go higher when I save for some new shifters (or get a bit older).

So when I read this on Sheldon's site

7-speed hubs only accept 7-speed cassettes --though 8 or 9 sprockets can be installed on a 7-speed hub, using 9- or 10-speed spacing. It is also possible to transplant an 8- 9- 10-speed cassette body onto most 7-speed Freehubs.

I begin to think that I'm going to get stuck unless I go the whole way in one.
But this says 7-speed hub so does that mean that the freehub bit is not changeable.

Or is it possible to get a 8-9-10 freehub and fit 7 speed cassette onto it with spacers.


So the real questions come down to: What speed freehub is a tiagre/105 hub going to come with and can I start with a 7-speed and change to an 8 or 9 only having to change the cassette.

I know the question is broad but I can't think of a simple question to get the answers I'm looking for.

Many thanks

[Brucey]

the tiagra hubs will come with an 8s compatible freehub body. You can fit a 7s cassette to this with a spacer.

However these hubs will be 130mm OLN where your old hubs will be 126mm and at any given OLN the dishing is worse on an 8s hub than a 7s one.

More gears seem attractive until you look at the ratios; an awful lot of cassettes start 11,12, etc which means that the 11T cog is almost useless.

So if you don't want to reset your frame and/or have a weaker wheel I'd suggest a 128mm spacing (which will spring into a 126mm frame easily) and a 7s freehub body. This will accept 7 from 8, or 8 from 9 etc. If you want to change the freehub body for a wider one later on you usually can do so.

BTW if you fit shimano cones into a Normandy hub you need to change the ball bearing size in one or other of the hubs, else you will experience rapid wear. I forget the details but it might be that the rear balls need to be 7/32" instead of 1/4". If you make this adjustment correctly the hubs will run very smoothly.

IME the cups in Normandy hubs fail by cracking; if you really want to you can replace them, and there are of course plentiful used spares of cones etc if you want to keep these hubs going.

cheers

[recordacefromnew]

The current Tiagra/105 hubs are 8/9/10 speed cassette compatible (although a 1mm spacer might be needed for a 10 speed cassette).

You can put a 7 speed cassette on a 8/9/10 speed Shimano freehub if you introduce a 4.5mm spacer before the cassette.

To understand what Sheldon was talking about, see the table at the bottom of http://highpath.co.uk/cycle-information-freehubs-and-cassettes/.

If you are interested in other freehub cassette compatibility (although it does not cover 7 speed per above), see http://www.slowtwitch.com/Tech/Cassette_How-To_-_Part_2_3257.html.

[cycleruk]

What Brucy is says is true but I have been running 130 OLN hubs for years with no problems from my wheels.
Yes I have had the odd broken spoke but nothing disastrous. I have wheels that are from the mid-nineties with 8 speed hubs that are still perfect. You will need the frame setting and the drop-outs re-aligning to take the wider hub spacing.
Regarding cassettes you can choose any variation you like from 7,8,9 or 10 and they will all fit the same freehub.
I have Tiagra, 105, Ultegra and even Dura-Ace hubs, with all giving good service. The Tiagra hubs are not now as smooth running as the 105s etc but are on my winter wheels and have done many thousands of miles.

[grognut]

Many thanks for the info.

Further googling I found that the tiagra's are 8-9-10 compatable.

recordacefromnew:
thanks for the link and the use of a 4.5mm spacer. I'll read the links later.

brucey:
The frame is 120mm ad I'm quite prepared to take this out to 128/130mm. I didn't know you could relace the cups on the hubs there doesn't seem to be a join mark to remove them. If I could get them out I'm tempted to make up some sleeves (i have a lathe) and use off the shelve bearings( suitable quality but easily changed. I do like the hubs and after 35 years you get used to the look of the bike. On a side note; I used my cousin's bike many years ago (40 ish) and the wheels on this were ball bearings. They just tapped out, cleaned and reinserted. I note from another of your posts that you have replaced cups. Do have a guide or some indication of how to do this. This could be the answer.

Cheers

Andy

[grognut]

cycleruk:

Thank you for your comments as well. Your post arrived while I was typing and went bed straight after my post so didn't respond.

My wheel was originally a 5-speed freewheel on a 120 OLN. I managed to get a 7-speed on it with a few washers. No broken spokes but then I only do about 1-2k a year.( but I am 15st (going down)).

So I glean in general that a well maintained hub will last me the rest of my life. Obviously from a reasonable quality hub.

Cheers

Andy

[Brucey]

re converting to cartridge bearings; you can do this but you will need an axle with accurately machined support diameters and (probably) shoulders on it. Sometimes you can modify cones for this purpose, but

1) cones are hard and difficult to machine and
2) the cones rob you of space for a decent size (strength) bearing.

I have made suitable axles by building up with weld metal and machining back. Obviously the welding and dressing needs to be 'perfect' else you will have made a bad stress concentration in the axle that will soon initiate a fatigue crack.

The cups can occasionally be knocked out from the back using a drift with a flared end. Some hubs (eg older campag ones) are designed this way. However in 'Normandy' pattern hubs there is usually no place to get such a drift in to do this. There are thus two main options you can work with;

a) machine a pocket behind each cup so that you can get a drift in there; easy with the hub in a lathe but also possible with the right kind of bit in a dremel tool or a die grinder.

b) attach something to the cup.

The latter approach can be (say) MIG welding a chunky bolt to the cup, so that it can be drifted out. The weld shrinkage usually collapses the fit of the cup slightly, so that they usually come out more easily if they are welded.

Other things that help to get the cups out are heat (even from a kettle full of boiling water; the aluminium has a higher CTE than the steel does) and having the hub in a built wheel; the spoke tension tends to stretch out the bearing pocket slightly. Once you have got the cup out you will usually find that the pocket is machined with a square seat, not a curved one; the exception to this in Mallard/Normandy hubs is in some later (often sachs-maillard branded) ones that are made differently. (These sometimes also have access for a flared punch from the start, because the hub castings are slightly different.)

The real stinker for a cartridge bearing conversion is to fit the bearing OD to the hub. IIRC the cup OD is not a perfect match for any known cartridge bearing. There are three solutions to this;

c) machine the hub ID some more
d) machine the bearing OD
e) make up a carrier for a smaller bearing.

I don't recommend c) for a rear hub because the wall thickness is already marginal at the base of the freewheel thread; hubshells occasionally fail at this point anyway. I've done both the other two with success; which you choose is probably a matter of how happy you are to grind a bearing OD down vs how likely you are to ever change the bearings; with a carrier you can source replacement bearings rather easily, but if they are made to fit then you'll have to do that all over again should the originals wear out. However I've successfully machined bearings (starting with a nominal 30mm OD) to fit Normandy hubs, and these bearings can be (in the most common sizes) both wider and way stronger than those which start out 28mm (say) so ought to last longer too.

BTW if you want some replacement cups, let me know, I can supply some good used ones at a reasonable price.

Also, it is worth considering an outrigger bearing if you tend to break rear axles (I do!).

cheers

[grognut]

Brucey:

Many thanks for spending the time to answer the query. I think your response should be a sticky somewhere.

I have spent most of the day think on and off thinking about this and I think if it wasn't for the difficulty removing the cups I'd have a go.
There were a couple of other factors one being that the rear hub was made slightly concentric so the freewheel always bobbed up and down as the wheel rotated which kinda annoys me. Other factors are that I don't like the 7-speed sora changers I have because they only have the button down shift and getting 7-speed better quality seems a bit difficult. ( unless I've caught a lean time on ebay).

So all in all I'm going to buy new wheels and upgrade the shifters later.

Many thanks

Andy

[Brucey]

if the freewheel runs out slightly this might be the hub but it is more likely to be the freewheel IME.

If you want quality shifters for 7s then do bear in mind that you can use 8s ones; these pull almost exactly the same amount of cable per click.

cheers

[scottg]

There are 120mm oln cassette hubs here, pricey and 6 speed max

https://www.compasscycle.com/shop/compo ... sette-hub/

OR
Ebay will have new 126 oln Shimano cassette hubs, tri-colour 105.
Buy a 10s 11-28 Shimano cassette, both the 11t & 12t cogs are 1st
position type cogs. Leave the 11 off, and use 10s shifters.
Shimano made 10s down tube shifters, easy to find online.

[Gattonero]

126mm OLD hubs are relatively easy to find on Retrobike or places like that, old Shimano HG for 7sp plus bar-ends will make for a system that works well.
Alternatively, Shimano does 7sp hubs that can be easily respaced to 128mm like Brucey said; they're not the best quality but most of them can have the freehub swapped to 8sp (thus taking 9&10sp if needs to).
I'd start with the shifters, if you want to use friction or indexed, hubs and rear derailleur go hand in hand with them