[Closed] Why isn't a combined freehub/cassette unit available?

1) It would make it more expensive and you would be throwing one away before the other was finished.
2) How much weight?
3) XD driver has fixed that
Also it would require a a standard freehub body for all hubs.

They've been available for many, many years 🙂

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Hope did it (prototype).Now they don't.

Also it would require a a standard freehub body for all hubs.

You mean it would lock you into using one particular manufacturer? Oh yeah they hate doing that lol

They've been available for many, many years

Not sure I understand your meaning here- that's a picture of a seperate cassette and freehub. Are you saying that they frequently seize up and can't be seperated? 🙂

Not sure I understand your meaning here- that's a picture of a seperate cassette and freehub

No, it's not.

they're called "freewheels" look them up

that's a picture of a seperate cassette and freehub

I wonder if maybe he means with the wheel bearings included, unlike a traditional freewheel

they're called "freewheels" look them up

Semantics, or stupidity on my behalf, you decide. 🙂

That's block. Freewheel is either a verb or maybe a single sprocket.

A freewheel can be single or multi speed.

Here's the hope prototype mentioned above...

https://www.bikerumor.com/2010/10/11/interbike-2010-trick-one-piece-cassettefreehub-and-other-goods-from-hope/#more-23380

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Here's the hope prototype mentioned above...

Yep, that was the sort of thing I was thinking of! 🙂

We defo need to petition hope for a production run on that.

Freehub bodies and cassettes wear at different rates, so this would add further expense for no real gain, and tie you into specific freehub mechanisms.

What I would like to see is interlocking sprocket carrier spiders integrated into the freehub to which the sprockets attach to directly, then can just replace the individual sprockets as they wear out.

Shops and distributors already have too many skus to ensure availability of. You'd also end up with a mix of fresh and worn cassette sprockets.

Not sure I understand your meaning here- that's a picture of a seperate cassette and freehub. Are you saying that they frequently seize up and can't be seperated?

Youngsters these days eh? 🙄 😆

These [url= https://tinyurl.com/ya3vemey ]guys[/url] amongst at least two other brands that I can think of do shimano splined one piece steel cassettes that prevent biting into crappy soft aluminium freehubs.

In my opinion the SRAM XD freehub is great but I'm surprised that SRAM don't do a range of XD road casettes yet.

TBF, the good old screw on, BSA threaded cassette/freehub that's been about for donkeys years could do exactly what the OP it on about, and could be designed to allow sub 11t sprockets as XD does, you would simply have to look at coming up with a new tool interface...

But then I don't really see much wrong with the HG cassette/FH design, and being limited to an 11t sprocket TBH.

Of course "real" blocks only had 4 or 5 sprockets. A nice straight through 13-17 was a proper job.

Of course "real" blokes only have 1 sprocket. A nice straight 16-19 is a proper job.

TBF, the good old screw on, BSA threaded cassette/freehub that's been about for donkeys years could do exactly what the OP it on about, and could be designed to allow sub 11t sprockets as XD does, you would simply have to look at coming up with a new tool interface...

I presume it's because the smaller sprockets end up under a fair bit of twisting load, the XD driver is a bit more supporting.

The problem with the screw-on system is the drive side axle bearing is far away from the dropout, the shimano freehub allowed the bearing to be spaced much further apart so axles don't bend.

so axles don't bend.

^ He means like a freewheel. Brings back memories of bending axles every other weeks on my Peugeot Ranger circa 1987.....

Cinelli bivalent
http://velobase.com/ViewComponent.aspx?ID=d227f009-3105-4ce6-a63e-0fbf626a634d&Enum=110

https://www.bikerumor.com/2014/11/25/d-fix-rear-hub-reinvents-wheel-removal-remove-the-wheel-leave-the-cassette/

Well that's a little different

An xd hub body still has the bearing away from the hub flange

But with modern hubs and axles you could go back to screw on freewheels without failures. And you could always get screw on hubs that did not bend/snap the axle under the largest cog just they were costly. Mavic pmp Royce hope etc all used to make good screw on hubs with sealed bearings

The problem with the screw-on system is the drive side axle bearing is far away from the dropout, the shimano freehub allowed the bearing to be spaced much further apart so axles don't bend.

Well that's a fair point, but XD doesn't generally offer axle support under the 10t sprocket, and most push-on cassette FH Bodies (like Hope) don't actually offer any real wheel support with those FH mounted bearings, and everything seems to be going to 12mm diary axles too now.

A "new" screw-on cassette form could be designed to provide bearing support at the end of the axle and work with larger axle diameters...

So my reasoning is this:
1) Cassettes have become sooo expensive anyway
2) It would save weight
3) It would stop that annoying 'cassette biting into alu freehub' business

Yeah, but no.

I used to sell Sachs freewheels and build them for timetriallers. The screw-on attachment could be a PITA, and freehubs and cassettes were actually lighter. I'm sure you could do it differently now, bit the freehub / cassette is still a pretty good system, especially as there is bearing support at the outer cogs where the most torque is generated.

Is that 'cassette biting into alu' really a big deal?

then can just replace the individual sprockets as they wear out.

I'd love this. I seem to remember someone trying it 20 odd years ago...?

But yes. The cassette system was an innovation - that's why it's called a cassette as opposed to an all-in-one system.

Is that 'cassette biting into alu' really a big deal?

I'd love this. I seem to remember someone trying it 20 odd years ago...?

But yes. The cassette system was an innovation - that's why it's called a cassette as opposed to an all-in-one system

Back on Shimano 10 speed you almost could ... if you used a 3rd party expander then of course that's replaceable on the XT 780 stuff and then anything else not on a spider... (replacing spiders seems non economic as it seems 80-90% the price of a new cassette )

https://www.sjscycles.co.uk/cassette-spares-shimano/?groupset=deore+xt

"3) It would stop that annoying 'cassette biting into alu freehub' business"

Softer aluminium, so the cassette sprockets could dig in to the freehub.
This would be a combined freehubcassette. Then when the sprockets wear out take the combined freehubcassette off and put a new (soft) freehub on and a new cassette and the jobs a goodun.

Screw-on freewheels have the problem that the right-hand bearings are very far in, so axles bend easily - but the Sachs Helicomatic system was very clever:

http://www.borgercompagnie.com/helicomatic/history.html

the ALU freehub damage comes from steel cassettes biting in. an aluminum cassette gets round this, but its more expensive. Iirc, the sprockets on that hope prototype were replaceable. It must be better than a screw-on freewheel 'cos you keep the axle strength.

the ALU freehub damage comes from steel cassettes biting in. an aluminum cassette gets round this, but its more expensive. Iirc, the sprockets on that hope prototype were replaceable. It must be better than a screw-on freewheel 'cos you keep the axle strength.

As do spiders by spreading the load ... but then the cogs themselves can't be replaced individually so a bit swings and roundabouts.

All of the free hub biting damage issues can be fixed with steel ribs/inserts on one or more of the splines though, like on some Novatec (and American Classic?) hubs, in engineering terms it's a non-problem as it's so easily fixed, I can only assume it's a patent issue stopping other manufacturers adopting it for their alu free hubs.

As do spiders by spreading the load ... but then the cogs themselves can't be replaced individually so a bit swings and roundabouts.

Nothing (other than cost) stopping individual sprockets being on an alu carrier to spread load and still be replaceable. The higher end Campag cassettes have carriers with pairs of sprockets on, which is almost close enough, but then they also have deeper splines on their freehub/sprocket interface anyway...

Shimano ones used to be bolted together with long bolts with a tiny head.

if they make them to be on a single carrier it wouldn't be a problem at all

Good point, like in the days of old.*

*Mid-90s.

Folks on here constantly moaning about new 'standards'.

Folks want a new standard that is more expensive for no benefit.

Bizarre.

Nothing (other than cost) stopping individual sprockets being on an alu carrier to spread load and still be replaceable. The higher end Campag cassettes have carriers with pairs of sprockets on, which is almost close enough, but then they also have deeper splines on their freehub/sprocket interface anyway...

About half the sprockets on the XT 780 11-36 were actually replaceable (and at a fairly reasonable price)
If you then used an expander then that was also replaceable.

But its down to cost.... the bigger sprockets are heavy in steel and fragile in alloy and presumably horrendously expensive in titanium so do you want a cassette that's all replaceable but costs £200 or semi replaceable and costs £60 ??

Equally the Novatec freewheel replacement including bearings is £35-£40 so cheaper than a cassette...
(Prices for the D772 on my kids bike)

In many ways its like BB's ... the Deore External is £15 ish (less than new bearings for a Hope one) so its a matter of light/strong/cost again.

As Nober say's we all moan about forced new standards ... so if SRAM/Shimano are essentially defacto standards then I've no problem with other companies making non-standards... (for debatable value/benefit)