Affix hub; specifications and internal details

[mig]

was the chain extremely tight? looking at the failure it seems that chainrings with un-used drillings in them aren't really suitable for fixed use.

[Dr H Tool]

Exactly, big mistake to use a TA touring crankset I had used in 1983 to tour France. I was chuffed with the serendipity of but the new chainring with, like you said unused grilling wasn’t up to it. I’m thankful it collapsed or!!!!!

Anyway all updated with proper components

[Dr H Tool]

Taken just before the incident. The replacement crankset is much better engineered so able to tension the chain a lot better, no snagging. I can’t wait for the Affix to be put on as the longer hills around here a pain to come down but the gradients mean you can sail up on fixed.

[Brucey]

the hub wouldn't change 'mode' itself. the movement of the ring is too much to happen by accident.

the fixed mode of the hub is merely 'okay.' it feels a little uncertain - not quite as solid feeling as a conventional set up.

IIRC the 'fixed mode' in the 'affix' hub uses drive transferred via an Al-Al 'pastrycutter' interface. This has some kind of a clearance from the start (else it would be impossible to ever change modes) but wear will only ever increase this clearance, hence the 'uncertainty'. I think this could be very greatly ameliorated using steel shim (beer can) and epoxy resin.

[Dr H Tool]

Over the past 45 years or so I’ve noticed that with increased fitness levels the range of gears used has decreased. Therefore it was a logical progression for me to go single speed. I would say that also meant less wear and tear and applying that logic to the Affix, unless you were on and off it at every hill the wearing down of the component would take ages and by that time you would be looking at scrapping it or as you say trying to resuscitate it,

[Brucey]

I think it would not be very difficult to improve on the affix etc, given a free hand.

[Dr H Tool]

Yep my thought especially now with Bluetooth. Plus it didn’t need ‘Push and Turn’ written on it, which is akin to a ‘Kick me’ sign on the back. I think it pretty obvious to the purchaser what it does or doesn’t do!

A minor issue really but impressed with it as it is and unlike anything electric which I prefer stay well clear of.

[rareposter]

I think it would not be very difficult to improve on the affix etc, given a free hand.

You could potentially argue that on pretty much anything ever made, the stumbling block is running into a cost / benefit ratio where you improve it by 0.1% but at a cost of £300 per unit extra.

And seeing as you can't buy them new any more, I'm not sure their demise was anything to do with how good (or otherwise) they are, it's more that the market for them is extraordinarily tiny - it's a niche within a niche and I'm saying that as someone who has owned a SS road bike for 20-odd years (and never once felt the need to ride it fixed!).

There are people (including me) who can admire the quirky engineering but have no use for it and there are about 27 people who might actually buy one and then the remaining 99.985% of the "people who cycle" will have no idea about it and wouldn't care even if they did know.

Plus it didn’t need ‘Push and Turn’ written on it, which is akin to a ‘Kick me’ sign on the back. I think it pretty obvious to the purchaser what it does or doesn’t do!

You'd be amazed at how necessary those sorts of instructions are...

[Dr H Tool]

A comprehensive reply Mr Rareposter. I can honestly say if you’ve ridden a Single Speed for 20 years and never felt the need to ride fixed you are missing a trick. Of course it depends on your objective but mine was the realisation that the guys I raced with back in the late 80s had an edge and it was down to riding fixed so of course I aspired to do it one day, albeit a bit late. I did do the velodrome but that is different. It was a baptism of fire and the local club members say it’s mad but after a couple of months of feeling like being punched in the stomach on climbs, bricking it on descents, feeling leg muscles I didn’t know existed and some upper body stiffness, bouncing in the saddle a few times I’m loving it and feeling at one with the bike. It is improving the experience of cycling hugely where I didn’t think it could after 40 years or so of cycling in most of it’s disciplines.

PS:- ) I suppose I’m not surprised most people don’t know what to do unless it’s written on the can.

[Dr H Tool]

The point I made earlier was that with a desire for ‘Souplesse’ I had already commuted on a restricted gear to practice, restricting it to a 65 inch even on a hilly route with a 32 inner as a safety measure. I felt it improved my cardiovascular system no end and I did other excercise for strength. I realised as I say that the fitter I got the less inclined I was to change down on inclines. Having the new frame made to measure was a no brainer as it was just like riding my old Neil Orrell frame albeit lighter. I had already started the not stopping pedalling, soft pedalling technique and it surprised me how quite intuitive when I got on the fixed it was. A bit of a side step from discussing the Affix but I find it interesting and as usual with cycling we find out mostly by ourselves how to do it properly with some help if we are prepared to listen.

[Brucey]

I think it would not be very difficult to improve on the affix etc, given a free hand.

You could potentially argue that on pretty much anything ever made, the stumbling block is running into a cost / benefit ratio where you improve it by 0.1% but at a cost of £300 per unit extra......

you would do that only if you are rather stupid. In the case of a fix-free drive I'd base it around a cheapish freewheel, modified to accept a novel (and largely backlash-free) locking mechanism, more pawls etc. This could be adhesively bonded to the hub in lieu of a lockring. A simple cable-operated control would allow the rider to switch remotely between fixed and freewheel modes via spring-loaded slip rings. The configuration would be arranged so that the default mode (ie. with a slack control cable) would be fixed. In freewheel mode, the slip rings would use about 1W or so (when freshly lubricated) which is probably OK given that the intended use of the freewheel mode is downhill.

The target retail cost would be around £125 for a basic kit (including a manual control to change modes), but closer to £200 for a complete kit (including remote control). Since the main wearing sprocket part is used unmodified, it should be possible to rebuild it (to as-new condition) without buying many expensive parts when worn.

[rareposter]

A simple cable-operated control would allow the rider to switch remotely between fixed and freewheel modes via spring-loaded slip rings. The configuration would be arranged so that the default mode (ie. with a slack control cable) would be fixed.

The idea of a fixed/free hub controlled by a "shift lever" is insane for the simple reason that activating the switch by mistake (or snagging / breaking a cable) on a long descent would rip your legs off. That's one of those things that a product designer (and the manufacturer's legal team) would look at and go "NOPE!"

Which is why the Affix is the way it is. And most of the point of it is that it saves swapping wheels (or turning a wheel around), so it doesn't need to be quick since no-one is going "ooh, I'll ride the next 500m fixed, then switch to free for a bit". You choose what you want for that ride and in the event that you do want to change halfway through, it's still quicker than turning a wheel around in the frame.

And in terms of my cost / benefit example, I was maybe exaggerating the figures for effect but the principle applies to anything. You could make it lighter / more durable / more efficient but it'll cost more.

Whatever you want to do to it in the comfort of your workshop is one thing; the factory-produced product as it is sold to the mass market (or in this case the very very tiny slice of a very tiny market) is perfectly adequate.

[Dr H Tool]

The attractiveness of it as stated in my earlier comment and very much in yours is that fact it alleviates the necessity to turn the wheel around. I was all for the flip/flop and spent a considerable amount of money on it, even bought a beautiful White Industries single freewheel. On realising that tightening the wheel nuts on the hop can lead to wheel shift I was very much attracted to the Affix and now I have one I’ll report on how I feel about it in a few months time.

Regarding cost it’s peanuts compared to the DTIs, AIs and all the other paraphernalia pushed at us by the bike industries. Besides descending doesn’t get one any fitter if that is the goal. I have my geared bike for that.

[mattsccm]

I am still trying to get the one i mentioned off the owner. When I do I'll let you know.

[Dr H Tool]

Yes do, you will be lucky as they are really rare.