The weight of a hubgear at the back of a bike can spoil the “feel” of the bike.

So, in light of the recent Drillium thread, has anyone lightened the internals of a hubgear?

Looking a Sturmey-Archer hubs, I can’t help thinking there’s a bit of metal that could be removed, eg waisting the planetary gears.

Obviously a good way to end up with a crunchy hub, but it must be possible to remove a bit of weight.

I was discussing the weight of my Alfine whilst out in a ride last week (my mate was running a Rohloff).

I actually like the weight, I find it easier to pop a manual, and it seems to work really well with a modern long, low and slack hardtail frame.

As far as drilling the internals goes, I imagine you’d save very few grams, and it’d then die! Prove me wrong though 😉

The gearing probably uses hardened steel, which won’t be easy to grind away.

cynic-al

The gearing probably uses hardened steel, which won’t be easy to grind away.

Presumably it would have to be softened and re-heat treated.

Bodger versus a design with 120 years evolution – don’t like the odds. 🙂

I have a spare hub, I may have a poke around and see what could be removed.

I suspect the greatest weight savings would be in the shell rather than the mechanicals.

The gearing probably uses hardened steel, which won’t be easy to grind away.

Although the OP of the recent drillium thread mentions EDM (Electrical discharge machining) which doesn’t have a problem going through hardened conductive materials.

Or perhaps you could re-produce some of the parts in ceramic.

Or you could move the assembly to where the crank is (pinion) to improve weight distribution.

Similar to what others have said, the parts in an AW hub at least are all hardenend, so if just drilling, then some ability to anneal and re-harden would be a must. Also, from the few I’ve serviced, the space inside is pretty well filled. You could possible lighten the gear and spring carriers, scallop out the sides of the planetary gears and I think that’d be about it.
I’m not sure if the Aluminium shells are any lighter, but I imagine they’d be thicker, so with access to a lathe, you could probably turn off a fair amount from the outside diameter of the shell. Otherwise:
28h hub shell? These are quite common.
Radial nds/2x ds lacing for a 36h hub.
Alloy nuts and spacers with the shortest possible axle you can use.
Also, if I remember correctly, the cogs are quite hefty, but quite hard too. You could drill or scallop one of those, use a 3/32″ rather than 1/8″ and use a smaller chain. Also using as small a cog and chainring combination will get rid of some mass.

I’m don’t really notice the weight on my Alfine 8 equipped Dialled Alpine with Lyriks up front. Maybe the answer is to make everything else on the bike heavier so you don’t notice?

Still, I’d be interested to see the results of any lightening efforts. I’ve got a bit of an obsession with sprung / unsprung mass ratios so I wouldn’t run a hub gear on a full susser unless the weight difference between a hub gear and a standard hub plus cassette, derailleur, and extra beefy spokes and rim needed because of the dish were reduced quite a bit.

The difference between the AW with a steel shell and the S-RF3 with an alloy is 125gms. I’m pretty sure the internals are identical, so the steel hub shell must be a fair bit heavier.

The bearing housing on the lhs of the hub is steel in both cases – if this and the hub shell were moulded in one piece in carbon-fibre maybe even more weight would be saved.

That’s something a bodger could try… 🙂

I actually like the weight,

Me too I loved all the extra snakebite punctures I got when i had a ‘Hoff hub…
Was almost as awsum as the extra drag.😳
Any extra weight should be in the middle of the bike.
There’s also a solution to that.😉

Sorry, I forgot you’re always right, and everyone else is wrong. Am I allowed to have my own opinion, please sir?

In MY case I feel that on my not particularly lightweight XL steel hardtail, with Marz 350cr forks (not the lightest put there) the weight centered in the back wheel gives quite a nice balanced ride.

People always moan about the weight of in gears being all in the back wheel, but with normal gears you have the cassette and rear mech in the same place. Personally I think a lot of it’s psychological 😉

Me too I loved all the extra snakebite punctures I got when i had a ‘Hoff hub…

Probably more down to a poor/heavy riding style. As I can’t say I’ve noticed the same issue.

That’s a very large chip on your shoulder there tom.
I’ll just leave you to it then as you seem a little sensitive to any opinion other than your own.

Nah, just the bollix you spout.
Happy Easter 😘

Yes it’s total bollix that the same bike on the same trails punctured more with a hoff than without isn’t it.
I also bet that it only dragged more just to disagree with you you great big bellend.😎
I love the idea of hub gears but the Hoff was quite franky a bit shit.
Which is a real shame.
Kind of put me off trying a Pinion which seems to be a much better idea but not going to splash cash on a frame that can’t be changed.

singlespeedstu

I love the idea of hub gears but the Hoff was quite franky a bit shit.

It’s not really, it’s just you are a singlespeeder. 🙂

I think I know what you mean though, I’d be just as happy with the Rohloff if it was a 5 or 7 speed but spread over the same range.

I think longterm SSers would be more comfortable with larger gaps. I find the Rohloff’s gaps too small so usually change up/down 2 or 3 at a time.

The gearchange however is shit.

Sorry Tom but I had totally the same experience as Stu with the added issue that my supposedly indestructible hub had to go back to Germany twice in 2 years to have new bearings fitted as it developed play in the hub . SJS cycles told me that this couldn’t happen as there were loads of bearings working in an oil bath . To their credit Rohloff fixed the issue both times at no cost and sent me a very apologetic letter when the wheel was returned .

there’s a really lightweight way of shifting gears that been around for ages, I forget what they’re called, beraillieurs or some such…

more seriously, I imagine they’ve probably taken all the weight they safely could out of them already. Use an old one!

there’s a really lightweight way of shifting gears that been around for ages, I forget what they’re called, beraillieurs or some such…

If turd-polishing was an Olympic sport…

TBH you don’t use an SA hub (or similar) for weight savings, it’s not really top of the intended target market’s priorities at least not as SA would see it (IMO).

It’s an ideal utility bike gearing solution, that they got almost bob on about 100 years ago, as with mechs since then it’s been minor refinements.

Mechs for all their dangling about in grime next to rocks are still the most efficient solution, offer the widest/finest range (or at least can be setup to) and are relatively cost effective, hence their continued prevalence.

I still like a bit of epicyclic magic though.

I’ll +1 stus total bolocks.

Every issue he had ive also had with mine….

Hateful thing.

Well who knew that different people could have different experiences ☺️
My issue with Stu’s comment, wasn’t that I disbelieved he’d had issues, just that my experience is different to his.

I’ve probably jinxed it now, but I love my Alfine. With minimal maintenance it just works well.

Wasn’t there a thread on here some time back where somebody weighed a bike before and after an Alfine conversion, and weighed all the components. The difference was only 100g or so.
I imagine with some of these massive 48-50t cassettes the difference might be even less.

Found it…Alfine weight thread

Is there any topic that the big hitters won’t ruin?

Is there any topic that the big hitters won’t ruin?

To be fair the topic had virtually no potential anyway . Seems like Tom likes his alfine whereas Stu , me and Trail Rat ( assuming he’s talking about Rohloff don’t like Rohloff hubs . No disagreement as we are not comparing like with like and the Alfine may well be a great bit of kit.

Well to be fair I had/still have a rohloff an alpine and a stumey archer 3 speed internal 9speed free hub.

The best of the three functionally.the sturmey archer.

But none of them compare to the balanced of the same bike assembled with regular derailleur gears .

When I got my first set of suspension forks (circa 1997) I remember thinking that it threw off the weight distribution of the bike.

Do you find when you switch from a suspension fork to a lighter rigid fork it messes up the weight distribution in the same way?

Well there’s circa 400grams between my sids and my rigid fork but your right I rarely notice it as it’s much easier to correct for such a small amount at the front of the bike due to the ability to move mass around relatively easy to balance for it because your mass is rarely directly over it and to an extent alot of the correction can be done through angles and bike design.

It’s a little different to 1.5kg difference directly at the centre of the back wheel where moving mass around quickly takes alot more effort because the bulk of your mass is situated across it alot of the time.

No one really designs for a rohloff at the back. You just sort of bodge it in. Even the thorn frame I had that claimed to be designed for a rohloff (by way of a big sticker on the stay)actually had no features other than the OEM plate and an ebb that made it any more rohloff specific than my ragley td-1 – which had a sliding OEM plate drop out

But they have their places. The alfines on my wife’s commuter and the rohloffs on my winter mud plugger – which incidentally is a fat bike and masks the weight issue marvellously

When I check the weights of an slx hub, cassette, and derailleur the total comes to 1425g. The Alfine 8 comes in at 1680g with another 145g for the fitting kit. You have the weight of the sprocket but let’s say you can offset that by the shorter chain needed. This means the difference is 400 grams.

Don’t forget that you can get away with a lighter rim and spokes because you don’t have any dish on the wheel. All 32 spokes are able to share the load rather than just the 16 on the drive side. You can probably save 150g in the wheelbuild.

Therefore, for an Alfine to match slx in terms of weight, you need to reduce the Alfine weight by 250g.

I doubt shaving grams had anything like the same focus when they were designing the Alfine compared to when they were designing the SLX so it’s not outside the realms of possibility a hub gear could be made to match a derailleur system if there were a demand for it.

I don’t think that the weight is the real issue with hub gears , if they could make them with no noticeable drag then they would be more popular .

Honestly if the Rohloff could be lighter without sacrificing reliability (or making it even more expensive) they’d have done it, they know fine that the weight puts off a load of potential customers.

Back on the topic of SA hubs….

The 135mm dropout / disc version was (still is?) achieved with a regular hub shell, longer axle and pile of steel spacer nuts. So if you’ve got a narrow spaced frame you could lose a chunk of that. Also stronger as the axle less likely to bend.

Mine also uses a short but regular freehub spline rather than the old style 3 lug Sturmey sprocket – so easy to fit a lightweight aluminium singlespeed sprocket. You can also flip it over to even-up the (very rapid) wear 🙂

Just put an SA 3sp in my Ss road bike. About 600 g extra

cookeaa

…Mechs for all their dangling about in grime next to rocks are still the most efficient solution, offer the widest/finest range (or at least can be setup to) and are relatively cost effective, hence their continued prevalence….

Although the derailleur was invented by Satan, I must admit the  XTR mech is a beautiful piece of work. I could fiddle with it all day, and admire it on my desk.

But I’m not the sort of mechanical savage who would drag such a fine piece of precision engineering through gritty mud, winter salt spray, or derange it by banging it off rocks or dragging it through heather. (And too tight to buy a new one every year.)

As an ageing singlespeeder, the occasional assistance of a few extra ratios has appeal. I have an assortment of hub gears, Rohloff, Alfine. S-A 5spd, and S-A 3spd.

Of these the 3 speed Sturmey is my first choice. I can do a 200km audax on it or follow sections of the HT550. Basically 3 speeds are enough for my needs at this stage in my decline.

However, seeing as I’m used to having virtually no weight at the back of my bike, it would be nice if what was to be added could be kept minimal.

I’ve just built a gravel bike (Highland version of gravel 🙂 ), and it would be nice to have a S-A 3 speed with the rotary change on it, but these seem to be available only in the USA (or at least the 32 hole version). The ordinary version has the change mechanism almost as exposed to damage as a derailleur.

Rather than put the Alfine on it, and upsetting the balance, I’ve dingle speeded it (42/19 and 39/22) to get gearing of 64″ and 51″

If anyone knows where I could get a Sturmey RS-RK3 32 hole (that’s important) I’d be most obliged. 🙂

In the meantime, I’ll dream of ways to lighten it.