Tag: Tech

#365daysofbiking Gearing up

January 3rd – One of my bikes uses a Shimano Di2 hub gear – an Alfine 705. This is the original Di2 11 speed hub and has its own pros and cons, but on the whole it’s reliable and workmanlike, and apart from a somewhat fiddly oil change when the shifting gets lumpy, requires little in the way of mechanical attention during it’s lifetime.

Generally, the life I’ve found is about 15-25,000 miles. This hub has been through a lot, and more than 3 wheel builds, but I’m happy with the wheel it’s in now, which was why it was so annoying when it suffered a serious failure on Christmas Day. I lost about half the gears which just spun out when selected – 3,4,5, 9 and 11 I think. An oil change and filling with cleaning oil hadn’t helped at all. The hub was knackered.

There’s not much I don’t know about this system; I’ve been using it in different iterations for over a decade and I’ve got to know the tricks and fiddles and advanced maintenance procedures – both by reading manufacturer documentation and by trial and error. The internal mechanism of the hub is easy to remove and change for another – you remove the wheel, take off the changer mechanism, sprocket and disk brake. You then remove the non drive side cone and locknut, then unscrew the plastic retainer and oil seal on the drive side – I have the right tool for this but a strap wrench will do it fine too, but the key bit is it’s a left hand thread. Once it’s off, the whole gubbins will come out, the oil can be cleaned out and a new mechanism can be put back, or the old one repaired and refitted.

There was a snag. The 705 is no longer available, but there is a new version, the 7051. I didn’t want to rebuild the wheel. I scoured fleabay and the web for a 705. No dice. I found a brand new 7051 in Germany for about £250, which is a great price. I poured over Shimano drawings of the two hubs. I decided to risk ordering the 7051 and trying to swap the innards. If they didn’t fit I could always reassemble it and build a new wheel.

In time the hub arrived, and the good news is it fitted exactly the same. On the rare chance that anyone ever reads this wondering if it’s possible to swap the two, yes it is. I swapped the guts, but also the non drive side bearing and oil seal too – be careful popping that out as they’re easy to damage and if no longer flat, oil will leak from the cone.

The 7051 hub has an upgraded clutch, smother shifting and performs better changing under loading. I have to say, fitting it back was a dream, and it runs well. Once the factory stiffness had gone, changes are much smoother and there’s far less clatter when doing so.

The old hub mechanism I plan to dismantle to see what’s gone. Looks like I’ll be spending some time in the garage with the tools…

This post has been created on the off change anyone ever wonders the same thing: I would say this also applies to the non-Di2 cable variants too.

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#365daysofbiking Springtime:

November 30th – I wondered how long it would be before this set of Rockshox forks suffered the notorious ‘sticky lockout’ problem. A year, they’ve been fine, the control on my bars reliably allowing be to make the suspension solid on road, then active on rough terrain at the flick of a lever.

Usually, it’s as simple as a corroded cable. Not this time. The damper gate appears to be failing.

Spares on order, and for now, a spring and a cable tie to assist the mechanism over it’s reluctance.

This must be the fourth iteration of these forks, all excellent on the whole, but all suffering lockout issues.

Time for a redesign, SRAM…

#365daysofbiking The daily grind:

25th November – A mechanical job that should have been easy was far from it. Replacing brake discs resulted in a struggle with seized fasteners, the failure of a brake calliper and the discovery that the parts I thought I had in the spares box brand new for this eventually were in fact the wrong ones.

The front disc was so badly worn it was starting to warp.

For a job I thought would take 15 minutes and leave me bags of time to get out turned into hours and I was lucky to get time for tea…

Perhaps I shouldn’t leave it so long next time.

#365daysofbiking Rime and season:

November 22nd – First really cold morning of the year I think, with lurking black ice and hedgerows and verges adorned with a hoar frost. It was the kind of penetrating cold that hurts your throat and forehead, and even though I was wrapped up, on the morning trail, towpaths and cycleways the -2.5 degree temperatures were still a little raw for me.

Every year it takes time to re-adjust.

I was certainly glad of the ice tyres this morning.

#365daysofbiking That’s some hammock:

November 12th – Back in Redditch and an ageing Dawes Ultra Galaxy – a classic British tourer – caked in the bike shed.

I don;’t know who this fine stetted belongs to, but I noted the nurse’s lock and Brooks leather saddle.

However well ridden and looked after, though, one thing stands out: That saddle. The tension has never been adjusted, and that is more like a hammock.

Bet that’s an interesting ride…

#365daysofbiking Still amazed:

November 9th -One thing I never take for granted is my biking technology. From disc brakes to LED lights to tough tires, things are very much better in the saddle these days than the four decades or so ago I started to ride a bike.

One thing that would have blown my mind even in the 1990s is the current GPS bike computer technology available to me. I ride down darkened lanes, with the soft glow of a device on my bars indicating my position on a scrolling Ordnance Survey map. Overlaid on this are street names, and I get warnings of sharp bends and hazards. 

Of course, I know these lanes like the back of my hand, but when off-piste, it’s a godsend. If anyone had shown the young me this device, it would have blown my tiny mind.

Old hands scorn the modern technology, but not really is a wonderful thing.

365daysofbiking Ladies, please:

October 8th – This is a post that will hopefully confine us to a mild winter.

After suffering a spill in November last year on ice while riding summer tyres, I’m taking no chances this year and have the ice studs on now as we’ve already had a couple of heavy frosts, and I’m, getting too old for the falling off lark.

My rubber of choice for the cold months is Schwalbe Active Winter 30mm which has a good tread and several hundred tungsten carbide studs that bite into black ice and keep me upright.

They are a little noisy, and although not slow, not the nippiest tyres in the world.

Now I’ve fitted them, expect it to be warm throughout the winter…

#365daysofbiking Telephone man:

October 3rd – I stupidly left my camera at work, but took some shots with the phone camera over Clayhanger Bridge going to the village to undertake an errand on my way home. The phone is an iPhone XS and althoughhe range in the images is a little harsher than I’d like, phone cameras have come a long way considering the obvious limitations of the physical design.

I quite like these images, showing the the Brownhills Canal is also showing beautifully the colours of the season.

I also loved the sky reflection on the canal…

#365daysofbiking Spring has sprung:

September 13th – Spotted in a customer’s bike shed, and improvised, clever repair to a brake calliper with a broken return spring.

The return spring – present in some form in nearly every type of brake – forces the brake off once the lever is released.

Since the brake cable pulls the yoke awards the cable end stop to engage the disc brake fitted here, forcing the two apart will duplicate the effect of releasing the brake as performed normally by a return spring. The spring has clearly broken and instead of replacing the whole calliper, the owner has released the cable, threaded on a very stiff spring and re-assembled the cable. The cable retains the spring and the brake operates as normal.

Clever. I’m impressed.

August 16th – A dreadful morning commute in heavy rain to the railway station was a shock to the system, on slippery roads with a worrying amount of spray. Getting to the station, when the train arrived I found I was sharing the bike space with a hardy cyclist in shorts.

Looking at his bike, a respectable singe speed, I saw what can only be regarded as the worst bit of rear light positioning I’ve ever seen.

Almost lower than the rear wheel, on the seat post behind the seat stays.

I hope this guy doesn’t do anything engineering-based for a living.