I mentioned at the end of my previous blog article on the Raspberry Pi that I had a DAC board in transit. Well it has arrived, I’ve fitted it and after a few trials and tribulations, it is set up and working well.The attraction of having an onboard DAC in the Pi is really one of neatness. It also frees up one of the USB ports that I would otherwise use to feed a USB DAC (for example I can boot the Pi into Squeezeplug, and use the Pi as a Logitech Media Server with Squeezelite as a player). The case that I’m using for the Pi doesn’t really offer a lot of room for manoeuvre when installing additional boards, but in the end I bodged together a neat enough solution.The HiFiBerryThe HiFiBerry DAC is a small printed circuit board about half the area of the main Raspberry Pi board. It attaches to a set of 8 connecting pins - the onboard sound connector P5 - you have to solder an 8-pin header to the Raspberry Pi main board first.I’d ordered the board with two RCA connectors, but no headphone style jack plug. The RCA connectors were three pin sockets, obviously intended to be soldered to the board. It was immediately clear that this would mean the Pi would no longer fit in the case, so I decided to connect the RCAs via wires to the board, and mount the RCAs in the lid of the case. The board came with the GPIO and P5 sockets already soldered.AssemblyStep 1 - I soldered the P5 header to the Raspberry Pi board. This proved pretty easy. The P5 sits right next to the GPIO connectors.Step 2 - I soldered four wires to the output terminals intended to output to a 3.5mm jack. Two from GND to the GND tag of the RCA sockets, and one from the L and R channels to the appropriate tag of the RCA sockets.Step 3 - I drilled two holes in the case lid. I also needed to remove some bits of plastic from what appear to be strengthening ribs in the case lid to allow it to fit over the HiFiBerry board. I fixed the RCA sockets into the holes, which needed a spot of araldite to hold them firm.Step 4 - I mounted the HiFiBerry board on the P5 connector - it also slots onto the GPIO header for added support. The card came with a polythene pillar and screws to further support it in place, so I fitted those.Step 5 - I assembled the case back together, inserted the SD card and booted the Pi.[caption id="attachment_2499" align="aligncenter" width="300"] Upper side of HiFiBerry board[/caption]You can see the wiring I added to connect the RCA sockets to the board. Obviously, the sockets supplied are intended to be soldered to the board in the positions labelled 'Left' and 'Right'.[caption id="attachment_2501" align="aligncenter" width="300"] The underside of the HiFiBerry board[/caption]There's not much to see on this view of the HiFiBerry - other than my soldering, and the two connectors that attach the board to the Raspberry Pi - the board came with these already fitted.Using the piCorePlayer web interface, I selected the option for the HiFBerry DAC, determined the ALSA settings for the HiFiBerry and entered them, and saved the whole setting to the SD card. Then I excitedly hooked up the phono cable to my amplifier, booted the Pi and sat back to listen to the music.Well, I could listen to the right hand channel, but the left channel was sadly absent!A problem!Clearly I’d done something wrong! I referred to the forums on the HiFiBerry site. Most people having this sort of trouble had evidently made minor cockups with soldering, though there were hints that some cards may have been defective. A quick email elicited a rapid response suggesting I check the connectors for evidence of shorting out. I did this, finding no problems. As an aside, I found Daniel at CrazyAudio very responsive and polite in the face of a neophyte solderer asking questions.A little while later, it occurred to me that the two non-ground pins of the RCA connector might not be equivalent - in particular, it wasn't easy to see how they connected within the socket. I plugged in an RCA plug into the L channel socket and used my multimeter to determine if the signal wire from the plug actually made electrical contact with the tag to which I’d soldered the wire from the board. It didn’t, so after a bit more investigation I detached the wire and soldered it to the third tag of the connector. At this point the Pi was properly outputting audio from both channels!Triumph!So, how does the Pi perform as a media player with the onboard DAC? First impressions are that it compares well with the two external DACs I have available, though both are budget items (a Cambridge Audio DACmagic 100 and DACmagic XS). More on this later, though I'm not really a serious audiophile and I've no way of doing a proper blind test.

I’ve been something of a retro-Luddite when it comes to gear-shifting technology. Party this is because I had several 9 speed race wheels, and I wanted to maintain interchangeability between bikes, and (I am embarrassed to admit) I found it difficult to figure out which parts I'd need to buy to set up a TT bike with Shimano Di2.Enter SRAM’s new electronic gear system, eTap. For road bikes, this is a pretty straightforward system. Each brake lever has one gear change switch, and it operates the derailleurs wirelessly. Satellite shifting switches (the ‘’blips”) allow shifting from the top of the bars or clip-on aero bars. The right hand control shifts the rear mech up, the left control down. Pressing both controls at the same time changes the front mech either down or up, depending on which position the mech is currently in.This spring, SRAM released the eTap Aero, intended for use on TT and triathlon bikes. I decided it was time to (a) get modern, and (b) get 11 speed. So I set my Wiggle profile to email me when the eTap aero was available. Ages later, I got an email saying it was in stock. I popped over to the Wiggle website to find four sets were available. I ordered one, along with an 11-speed Dura-Ace cassette and an 11-speed SRAM chain.The box.A few days later a vast box arrived at work. The post room called saying they thought a wheel had arrived for me! Inside was the cassette and chain, and an enormous and very heavy black and red box that just exudes quality.[caption id="attachment_3638" align="alignnone" width="474"] This image shows the six smaller boxes (sourced from the Slowtwitch forum, and edited)[/caption]Inside that were six smaller but equally robust boxes containing:

1. USB battery charger. This comes with all sorts of wall socket adapters, and is for charging the derailleur batteries.
2. The rear derailleur,  with the battery detached. The red part covers and protects the attachment point of the battery: there's a complementary part to protect the battery - the front derailleur comes with identical parts.
3. The blipbox. This is quite small, and has a Garmin style twist mount, there are several included. Neither mount with self adhesive pads matches the curvature of the top plate of my aerobar, so I used the normal Garmin mount held in place with stretchy bands (but see below).
4.  One USB stick for firmware updates. Just the USB stick. Nothing else other than a few scraps of paper.
5.  The front derailleur. This has the battery detached for transport, and a buch of weird little wedgy things, about which more later. Also, it has a horribly alarming sticker saying you MUST read installation instructions before using it. You need to retrieve said instructions from the SRAM website.
6. Two sets of 'blips' (i.e. four blips in total). These are the switches that connect to the 'blipbox', which actually controls the derailleurs wirelessly. So, not much in that box.

Underneath these six boxes is a set of brake cables (inners and outers), the presence of which completely mystifies me. I assume that the eTap aero set would be bought either to upgrade a TT bike (as I did) or for a new build. Neither scenario would seem to require a set of brake cables to be supplied, though no doubt they will come in useful in due course for another bike project (my TT bike has hydraulic brakes).Sadly, no Haribo gummy sweets were present.InstallationI began by fully charging the derailleur batteries. Because the front and rear derailleurs use exactly the same type of battery, if the rear runs out of juice, you could always swap in the front mech battery. The instructions provided observe that when the battery is detached, both the battery and derailleur need to be protected by the plastic parts supplied to protect the connection parts. I believe the system is activated by motion sensors, and the recommendation when transporting the bike by car is to remove the batteries to avoid unintended discharge.Installation turned out to be stupidly straightforward. In fact, the biggest hassle was feeding the blip cables through the base bars, but a little ingenuity sorted that out. Pairing the three components (rear and front mech, and the blipbox) took less than 30 seconds. On my TT bike, the wires from the blips pass through handlebar setup internally, using the pre-existing slots cut for gear and brake cables (the P5's hydraulic hoses are entirely internal). Deciding where to place the blips on the base bars and aero extensions took a few minutes, before I taped the bars. And then a test. Well, the controls worked well, though the rear mech wasn't quite aligned with the sprockets. A quick perusal of the manual showed how to fine-tune that. Then all was done.You might be wondering about that alarming sticker on the front mech. I can only assume that refers to the funny little wedge pieces that apparently brace the mech against the seat tube of the frame. It's not obvious why these are needed, but I complied.UsageSo, I'm using a Campagnolo Record chainset with TA rings, SRAM mechs, SRAM chain and Dura-Ace cassette. Does that combination work? Well, on the basis of riding out to a 10 mile time trial, riding the event, and riding back, I'd say so. Shifting was very smooth (I might even suggest too smooth - I did miss the positive click of my old Dura-Ace levers), and I found the usage of the blip switches really very intuitive. I made no inadvertant gear changes, though to be frank I didn't do many changes with the front mech.Battery life presumably depends on the number of shifts you do. The blipbox uses a CR2032 cell, which i supposed to be good for over a year. Each derailleur has a rechargeable battery supposedly good for 1000km/60h of use. The system uses the same battery design for both mechs, so they are interchangeable.In the week following my first ride with the system, I revisited the mounting of the blipbox. Its garmin mount section is threaded for a screw, so I drilled the top plate of my aero bars, and fix it in place that way. It's a fair bit neater than the elastic bands!I rode the system in the NBRC Hardriders club '20', and did have some hassle with my mongrel transmission - the chain didn't want to seat properly on the inner ring. Hopefully I can sort this out without resorting to a new chainset.Worth it?Well, it's nice. It works well (faultlessly so far on my limited riding to date). I now have 11-speed on this TT bike. It doesn't require any guddling around persuading cables to pass through the frame. I am pleased with it. But does it represent a major performance improvement over the old style mechanical Dura-Ace it replaced? Well, I'm not sure, though I very much like having a second set of controls near the brake levers. I can say, though, that were I to spec out a new road bike, a SRAM eTap group would be high on my "to buy" list.Longer term, I'll do an update on performance (part 2!).

In Part 1 I described the hardware I use for cycle training indoors. In Part 2 I’ll describe the principal software package I use for indoor training, TrainerRoad. Part 3 will cover the other software I use, and Part4 the software I use for monitoring my progress (with some hardware comments).

There's a wide variety of apps out there for use with smart trainers. For some of these I'll only give a brief description in Part 3, while others I'll keep my comments very brief as I haven't used them extensively enough to form a valuable opinion.

Part 3 of this series is somewhat delayed by Christmas and associated shenanigans such as the traditional Christmas Cold, which really flattened me for a couple of weeks.

A supremely comfortable saddle for touring use. Possibly my oldest bike component that is still in use (even if only occasionally).

During a recent garage clearout, I unearthed this saddle. It's clearly seen better days - the surface of the leather is a bit cracked and the rivets are a bit green! These photos were taken after I applied some Proofide.

In which I review the power meters I've been using over the last few years. All of these seem to be accurate and consistent in their data. This is a brief review of the four systems I currently use - and to cut to the chase, of these four power meters, which would I recommend as a power meter on a new bike build?

Given that two of these power meters are discontinued, the choice comes down to the SRAM Red chainset or the Assioma Duo pedals, and from the viewpoint of easy transfer between bikes I'd recommend the Assiomas (which can also be bought in a version to be fitted to Shimano pedal bodies). I should add that all four of these power meters have been absolutely faultless in use.

Hed H3 wheels are  probably Team Grumpy’s go-to wheel - they are pretty close to being indestructable (but not invulnerable) - they aren’t likely to go out of true as there aren’t any spokes to break or lose tension. 

In use, I’ve always found them to handle well except in the windiest of conditions (see for example the 2018 edition of the Duo Normand when I ended up using a regular spoked wheel). In comparison to very deep rimmed spoked wheels, they seem to be more of an all-rounder aero wheel for time trialling.

A few months ago, I reviewed the Shand Stoater bike that I’d bought as a problem-free commuter bike / tourer / winter bike - it’s equipped with a Rohloff hub gear and a Gates carbondrive belt rather than derailleur gears and a chain. Since then, I’ve used the bike a couple of times a week as a commuter (the rest of the rides to work are on a tandem), and out twice a weekend for club runs and the like. In that time, the only mechanical problem I’ve had has been a repeated puncture caused by a tiny black thorn in the rear tyre - so small and black my ageing eyes couldn’t spot it. Other than that, it’s been great fun to ride - and even dealing with a rear wheel puncture has been a lot less messy than with a chain.

This is a longer term follow up to the previous postings on my experiences with the SRAM Red eTap Aero derailleur system. I was an early adopter, buying the eTap aero kit in early 2016. A bit of a glitch occurred in November 2016 when the BlipBox malfunctioned, and this was resolved later that winter.

Until recently, the system has functioned flawlessly, and indeed I've liked it so much I sourced parts (mostly via eBay) to fit out my P3C bike with it as well. As you'll see in this report, I've had a recurrence of the BlipBox issue, and this caused me to look into buying a replacement, which turns out to be not only expensive, but near-impossible through my usual retailers.

This is a longer-term update: I've ridden with the eTap Aero group on my Cervelo P5 for pretty much the whole of the 2016 season, from mid-March through to my traditional season closing event, the Duo Normand in late September. During this period, the set has performed flawlessly. Until the end of the season, that is - see the end of this report for more on that.I did find that the old style Campagnolo Record chainset, which was 9-speed and with a pair of third party TA rings, wasn't ideally suited to the 11-speed transmission. In fact, I found that the chain tended to drop between the rings. So in the end, I decided to buy buy a newer model. I like the Campag Ultra-Torque system, so I stuck with Record - though the new four bolt rings seem to a bit more inflexible regarding third party chain rings. Still, 53 x 11 ought to be big enough for anyone!One of the particularly annoying things about the (frankly rather expensive) eTap Aero set was the lack of sensibly designed switches for the ends of the handlebar extensions. Initially, I mounted the blips on the underside of the extensions, just down from the ends of the bars. This has the effect of requiring a distinct movement of hands to effect a gear change, which wasn't ideal. So I mounted the blips by virtue of classic bodging into the ends of the extensions. This worked well, and served me well until the end of the season, by which time SRAM had finally brought out *proper* extension-end switches, called **clics**. Mind you, these are unreasonably expensive for components that by right ought to have been part of the group to start with.Above: modified blip switches, mounted in the ends of extensions. This bodge involves bits of bar plug, tub tape and black insulating tape!Below: The real McCoy - expensive SRAM clic switchesDuring use, I had no issues with batteries running out. The Garmin 520 I use links well with the eTap system, with display options such as current gear selection (which is surprisingly useful) and battery status. the Instruction leaflet cautions agains transporting the bike with batteries attached in case they discharge - the gear mechs are motion sensitive. In use, i didn't find this an issue for drives of up to an hour to an event, and even the 12h journey to Normandy for the Duo Normand.I do have a problem with the eTap system to report. In November, shortly after the racing season finished, I noticed that one of the inputs to the blipbox was no longer functioning. By switching blips between the inputs, I concluded that the input rather than the blips was at fault. I arranged a return to the mail order supplier in mid-November. At the end of December, I am still awaiting a replacement blipbox. This rather unsatisfactory turn of events somewhat reduces my enthusiasm for the eTap system. It's not clear whether the issue lies with the mail order supplier or with SRAM (who may have supply problems). More later on this.

Just a brief update on my last posting about the SRAM eTap Aero kit. I now have a fully functional eTap set up on my main time trial bike, almost two months to the day that I first reported the defective blipbox to the mail order retailer.Since mid-December, I've periodically communicated with the retailer by email (though it's not been obvious who to email) and via Twitter direct messaging. I've also contacted SRAM via Twitter and then email, to try and get a handle on where the problem has been. As far as I can tell, there have been supply chain problems somewhere along the line, though there seem to be some startling communication problems within the retailer.Anyway on Tuesday I received an email telling me the replacement blipbox had been packed and posted for next day delivery. About half an hour later, I received a second email (from an other person at the retailer) saying that the blipbox had been listed as present in a consignment, but that it was missing, so a further delay was to be expected. I replied, querying this information, and got another email saying they'd got it wrong, and the blipbox was indeed out for delivery.And it arrived, first thing the following morning! That evening, I fitted it, paired the gear mechs, and all is now fine with my time trial bike. The whole sorry tale has been a bit of a saga, and I am at least rather pleased it happen out of the main racing season.

2013 was a bit of  a mixed bag for me cycling-wise. In terms of results, my racing was decidedly sub-par. We didn't have our usual cycle tour in Scotland. But I did at least hang in there and not give up!Time Trials. Once again, illness and injury really hammered my season, and I found form very difficult to come by. I suppose my advancing years didn’t help! Things were looking really good up until Christmas 2012, when I fell ill with a horrid cold that left me with a hacking deep cough that took an age to shift. Then when it did shift, I put my back out (once again) that set my training back to at least April. Most of the year seemed to be spent desperately trying to get under the hour for 25 miles, which was not good at all! I didn’t race at any distance above 25 miles this year, and in fact rode only a few open events, probably my lowest number in any season in the last decade.Once resumed, training seemed to go pretty well, though I was still far from fully fit when Team Grumpy regrouped for the 2013 Duo Normand. We were therefore rather pleased with our second place in the Corporate category since one of us was rather unwell, and we had no realistic chance of beating the eventual winning team anyway.New tandem. Following our second front tyre blowout on the Dawes touring tandem, and taking into account the bike’s age, we decided to take the plunge and fork out a wad for a new Thorn tandem. This was quite a big step, and we made the most of it when specifying the kit for the tandem. Notably, we plumped for S&S couplings, which means we can transport the tandem inside our car (albeit with the back seats folded down) rather than on a roof rack. You can see my multi-part review of the tandem elsewhere on the site (Part 1; Part 2; Part 3; Part 4; Part 5). Suffice it to say that six months down the line we’re still happy with the tandem, though the flat stoker bars had to go. Needless to say, the Dawes hasn’t been disposed of, and we now house three tandems!Changes to our work calendar meant that we had no Scottish cycle tour this year, but two trips to Normandy compensated. We took the new tandem to France and had a great time in very nice (some would say too hot) weather. Plenty of excellent food, too.Team Grumpy. As far as I can recall, the 2013 Duo Normand was the only 2-up outing for Team Grumpy in 2013. We did regroup for the Port Talbot Wheelers ’25’ in early March (our usual season-opener), but unfortunately my back was so painful I could barely stand. Unsurprisingly, we didn’t ride. Anyway, given Team Grumpy’s lack of form, the Duo went pretty well, indeed better than we might have expected, particularly given the aftermath of a nasty cold suffered by one of us. We to second place in the Corporate category (behind a team that we frankly had no chance of beating, barring misadventure).New kit. For the last few years, I’d been using the ‘poor man’s power meter’ - the Polar system that uses chain tension and vibration to estimate power output. When it worked, it did well, with consistent data values (though perhaps on the high side). Unfortunately it was so unreliable as to be pretty much useless on a day to day basis. Eventually I cracked and coughed up for a Hed Disc with a Powertap hub. I selected this over other systems for several reasons. Firstly, I wanted an ANT+ power meter so I could hook it up to my Garmin Edge 500. Secondly, I wanted something that could be easily transferred between bikes. Reading up on the ANT+ Garmin pedal based system led me to believe that switching the pedals between bikes might not be so straightforward, and the crank-based systems aren't really an option for rapid shift between bike.The Hed disc wheel was quite pricey, but is so much easier to use than the Polar system. It delivers data to the Garmin Edge 500 via ANT+, connects reliably and calibrates easily. I’ve been using this not only for time trials but for turbo training as well (it’s effectively a spoked wheel with bonded on carbon sheets). I still don’t believe that training to specific power levels is necessarily the best way, and actually think that training to a measure of one’s physiology is smarter - i.e. heart rate.

Astonishingly, two weeks after I placed the order for the new tandem, I received an email notifying me that it had been built and was ready for dispatch. I say 'astonishingly' because I'd been led to believe it would take about 6 weeks for delivery. And so I took delivery of an enormous and unwieldy box.

Can anyone explain why tubeless tyres are such an advantage for road bicycles?  The push towards tubeless tyres is exemplified by this review of Easton tubeless aero wheels at Velonews. Early in the review, we see this:

Cars, motorcycles, and mountain bikes use tubeless clincher-style tires almost exclusively. Road bikes are one of the few wheeled vehicles that still rely on tubes to hold air. And tubes go flat.A clincher rim with a solid spoke bed (and a few design tweaks to help the tire bead seat against the rim) is capable of running tubeless with minimal changes. A special valve, a tubeless-specific tire, and a little sealant are all that is required. Nipples thread into the inner diameter of the rim. And if anything goes wrong with the tubeless setup, these wheels can be used as standard clinchers as well.The EC90 Aero 55 clincher was designed to run tubeless without the additional headache and pieces involved in converting a standard clincher. More shallow aluminum (read: not aero) road rims wheels are adopting this construction, and the EC90 Aero 55 is the first aero wheel to do so. Tubeless specific tires are thicker than standard tires, so rolling resistance is a factor when deciding to use a tube or tubeless setup for a race, although practically eliminating flats is a very appealing advantage.While tubeless road wheels haven’t yet exploded as they did for mountain bikes, nearly 30 tubeless tires are currently available and the number is growing.

I really wasn't aware that mountain bikes almost exclusively use tubeless tyres - is this an American thing? Apparently the fact that tubes puncture is a reason to go tubeless - but to puncture a tube, the tyre has to be punctured first. And it seems as though the response to puncturing a tubeless tyre is to put a tube in, and that'll presumably be mucky with the sealant that's needed!  Oh and only a few tyres are available, and they tend to have higher rolling resistance.I can't help feeling that tubeless road tyres are a solution in desperate need of a problem! On the other hand, I presume Easton figure there's a market out there for high spec tubeless wheelsets.

This is merely a brief addendum to the previous four parts of this tandem review, and really addresses any additions and/or modifications to the original spec of the tandem as delivered. While I think this tandem is a real tandemist's tandem - by which I mean that the frame and component choice have been really well chosen - I do think that fine-tuning even such a high quality tandem is inevitable.

A few years ago, I decided to have a play with using a power meter in my training. Because I wasn't too sure about how useful I'd find this, I went with the cheap option - a Polar CS600X with WIND speed and power/cadence sensors. This worked reasonably well - at first - but I've had no end of problems with reliability. Mostly this seems to be because there are several essential components in the WIND power meter system: the power supply, the chain tension sensor, the cadence sensor and the chain speed sensor. If any one of these elements doesn't work, you see no power or cadence reading, and there is virtually no diagnostics available to figure out where the problem lies (except if there is no power). And what is particularly annoying is that the setup can work fine one day, and the next (with the bike not moved from the turbo trainer) it doesn't the next day.Anyhow, enough was enough, and I decided to move to one of the more 'serious' power meter systems. I was looking for something that could be moved from one bike to another, that used ANT+ (I am so fed up with the Polar proprietary system), and that would be reasonably robust. I thought through the following options:1. The Polar Pedal system. Not ANT+. Seems from reviews that the pedal installation is fiddly so not easily switched from bike to bike.2. The Garmin Vector system. Despite winning a product of the year award from a bike magazine a few years ago, this hasn't been released to the public yet and remains effectively vapourware. It also uses an undesirable (to me at least) pedal system - Look Keo - and may well be prove to be a fiddle to install the pedals as with the Polar system. At least it is ANT+. I should add that I've not got anything against the Keo pedals, but I've no desire to add Keos to collection of pedals that includes old-style Look, Campagnolo Pro-Fit, Shimano SPD and Speedplay!3. The Brim Brothers system where the power meter is within the shoe plate - seems attractive, but what's the release date? At any road, the system seems to use Speedplay shoe plates.4. SRM - the industry standard crank based system. Clearly the system to have above all others, but it's expensive and not easy to switch between bikes. It is ANT+.5. Other players come and go...6. Powertap. This is what I plumped for. I went for a Hed Jet disc wheel with a Powertap G3 hub. This is a spoked wheel with a permanently bonded carbon fibre cover bonded to the rim and hub. It seems to be a robust construction (though the skin is pretty thin and flexible), and I am proposing to use it while turbo training as well as on the road.So far, I've had the device for a few weeks, and I can make a few observations. Firstly, the ANT+ system is a godsend, particularly as it relates to the Garmin 500 computer that I use. I've only used the wheel for a couple of events, as bad weather and a combination of leave and working away from home have interfered. I can observe that typical wattage is considerably lower than recorded on the old Polar system. But that's kind of what I expected, and I am only using these data internally as there's little point in comparing with other riders or power meters. I'd add that the Garmin 500 offers quite a bit of versatility in how data are displayed. I've decided to set one of the screens to include Power, Power (3 sec average) and Power (30 sec average). This offers not only an instantaneous power value, but a rather smoother and stable figure. The Garmin's data are easy to import into Golden Cheetah.As a disc wheel, the Jet disc is different to disc wheels I've used in the past. My first disc was a Hed with a screw-on hub - this had a rather cardboardy feeling carbon structure and was hollow and symmetrically lenticular. This disc was sold and replaced with another version with a cassette (currently adapted for fixed gear use). I've also got a Corima disc, which appears to be a foam core with carbon skin, and is flat-sided. The Jet disc wheel is essentially a spoked wheel with a thin carbon sheet covering the spokes - sort of a fairing. It has therefore got something of an asymmetric lenticular appearance because of the wheel's dishing. The skin feels a bit flimsy, particularly around the valve hole, but has stood up to use rather well so far. The skin is firmly attached to the hub and is bonded to the alloy rim. I chose a clincher version, as I've pretty much abandoned tubulars for all but the best of road conditions - around where I live I was suffering too many punctures in recent years. I imagine that a 'normal' Jet disc would be quite light though with a Powertap hub, even the lighter G3 version, the weight is a little hefty.Expect a longer term review at the end of the 2013 season.

I can safely say that since I took up cycling again in 1990, I've not experienced such a dreadful start to a season as this year. Following a horrid cold (and subsequent post-viral fatigue) that effectively took me out of training for nearly a month to late January, by the end of February I had dragged my form back to where it had been in December. Then, I ricked my lower back again. This had the effect to making climbing on a bike sufficiently painful that I was unable to train for at least three weeks.During that period, I tried a race (the NBRC club event in early March) only to find myself housebound with backache for a couple of days), and failed to start the Port Talbot Wheelers 2-up 25 in mid-March. Following that, the NBRC club event at Astwood was thankfully abandoned due to snow - thankfully because I might well have been tempted to try riding it.The final club event of March was the so-called 'Hardriders 22' - this was held on a cold morning with a heavy frost. I rode out to see the start, but declined to race as I was a bit worried I'd aggravate my back injury which by this time seemed to be on the mend. Indeed, in the last week of March I've been able to resume training, albeit restricted to the joys of the turbo trainer.Talking of turbo training, for some time now I've been using the Polar chain tension power meter to keep an eye on my training progress (see the review in six parts). Unfortunately this has been going through something of a hiatus after I unshipped my chain at speed, and it has proven rather difficult to coax the unit into working again. The explanation is that debugging problems with the device is rather complicated as the power unit is complicated to both set up and keep working. Complicated because there are three separate components:1. The main sensor/transmitter. This picks up vibration in the chain, so needs to be the correct distance from the chain, but also positioned correctly on the chainstay. This requires judicious positioning in 3D for it to work consistently. The second function is to collect cadence data from the magnet on the crank arm. So the position of the sensor on the chainstay needs to take proximity to the crank arm magnet into consideration. If either of these don't work, no data is sent to the head unit, with no indication where the problem lies.2. The chain speed sensor. This is mounted on the rear derailleur, and the instructions aren't terribly clear on its exact positioning. As I discovered yesterday, if it isn't just right, no chain speed data are obtained. If it's incorrectly positioned, the system may work in some gears only. The chain speed sensor is connected to the main sensor by wire - this connection can fail. If this doesn't work, no data is sent to the head unit, with no indication where the problem lies.3. The battery pack. Batteries can wear down, and the connection with the main sensor can fail. If this doesn't work, no data is sent to the head unit, with no indication where the problem lies.So, you can see that there are several points of failure, with no real diagnostics in place. If any point fails, the main symptom is that no power or cadence is displayed. This is the main reason I'm dissatisfied with the system. The most recent problem related to the position of the derailleur mounted chain speed sensor, which isn't something that I'd suffered before, and frankly it hadn't occurred to me! I'd think about reliability issues with any power meter system that I were to consider buying in the future. For the time being, I seem to be able to get along with the Polar system and I'm not inclined to change just now - though the cleat based system from Brim Brothers looks interesting (but may ultimately never be released).So, to end in an optimistic frame, I'm hopeful that I've turned the corner and training can resume. I may even unwrap the CTT Handbook.

Back in January of this year I posted an article (Unreleased products top cyclingnews.com 2010 tech innovation poll!) pointing out that two 'products' that had been awarded a best product award for 2010 had yet to emerge onto the market.  Well, bikeradar.com now reports that the Garmin (formerly Metrigear) Vector pedal-based power-metering system faces release in March 2012 (Garmin Vector pedal power meter available in 2012).  Not bad for a product that won an award for technical innovation in 2010.Somewhat annoyingly for me, the device now uses Look Keo pedals, rather than the originally slated SpeedPlay system (none of my bikes have Keos, but two do have SpeedPlay).  No word currently on whether Polar's parallel system, which is also based as far as I know on the Keo pedals, will see retail shelves in 2012.The Garmin system does look pretty neat compared with crank-based systems.

This is a listing of my favourite iPad apps:Dropbox - Absoutely invaluable for shifting files too and from the iPad; synchronise files between iPad and other computers; useful for collaborationsSqueezepad - Excellent and easy to use interface for Squeezebox Server.  Logitech's series of Squeezebox audio devices are really rather a nice way of managing and playing digital audio files.iAnnotate - read and annotate pdf files.  Aji Reader Service can be used to synchronise pdf files between Mac or PC and iAnnotate.  I use this to synch my pdf collection which I manage on the Linux and Mac notebooks using Mendeley.  Unfortunately the current version of the Mendeley iPhone/iPad app leaves quite a lot to be desired.iWork - three iWork applications have iPad versions: Pages, Numbers and KeynoteSkype -VOIP telephony via the iPad.  No video of course, but the rumoured second generation iPad may have video.  Works well on my WiFi model iPad.The Feed -Interfaces with Google Reader to help keep on top of your RSS feeds (I usually follow around 120 or more feeds).Tweetdeck - Not quite as full-featured as the desktop version, but still pretty good for emitting thoughts into the twitterverse.  Has a useful browser panel.Headspace - A kind of hybrid task manager, planning, to-do list app that is really quite versatile.  Three dimensional effects!Wolfram - Very useful if your web searches aim to pull out numerical analyses.  Reasonably good value when I got it on special offer, but I guess one could always access Wolfram Alpha via Safari.  A bit too focussed on American data.Notes Plus - very versatile note taking app, with diagrams and text.  No character recognition - for this try WritePad.  Works best with an iPad stylus.Quickoffice - read and edit MS Office documents.Penultimate - a neat and easy graphic note-taking app.  Works best with a stylus, otherwise you're finger-painting

I am wondering if I am turning into a Mac Fanboi...I recently bought my first Apple computer (I don't really include iPods or iPads as computers), in the form of a 13" MacBook Pro.  This purchase came shortly before the release of Ubuntu GNU/Linux 10.10 (Maverick Meerkat), of which more later.  Over the years, I've had computers running Windows 3.1, 95, 2000, Me, XP, Vista (possibly my least favourite) and most recently Windows 7.  Since about 2000, I have been using Linux, starting with an ancient version of Red Hat, then Mandriva, and for some years now, Ubuntu.  In fact I've rarely used Windows except for specific applications in several years now.  The Windows 7 desktop PC was bought and promptly set up to dual boot; the Vista notebook (a Sony Vaio) was so woefully underpowered for Vista that it was first used as dual boot with Ubuntu, then the Vista partition scrubbed.The trigger for this purchase was my experience giving a presentation at a conference recently.  I had an 8 minute (!) presentation to give: this was straightforward, except I wanted to include a brief video.  My Linux notebook running OpenOffice.org flat refused to project the video, using Powerpoint 2003 via Crossover Office, I couldn't even embed the video.  Switching to my Windows 7 desktop PC and its trial version of Office 2007, I was delighted to be able to embed the video and get it to function.Of course I needed to check the presentation at the conference.  Powerpoint 2003 on an XP machine wouldn't run it.  Powerpoint 2007 on the projection system wouldn't run it.  Powerpoint 2008 on the Mac presentation system wouldn't run it.  This was less than 24h before I was to deliver the presentation.  I ended up processing the video on the Linux notebook and regenerating the presentation on Mac Powerpoint 2008.  Nerves of steel I do not have, so this was undesirable pressure.I've had the MacBook Pro for a little over a fortnight now: other than iWork (which I obtained at a significant reduction), all the software I've installed has been open source: Firefox, Chrome, GIMP, Inkscape, Mendeley, OpenOffice.org, and FileZilla to name a few, thereby recapitulating quite neatly my experiences with Linux.  The hardware and build quality of the MacBook is second to none (it's annoying to have to buy an adapter to make a presentation, but the power brick is so small as to be genuinely portable).In the meantime, I've updated a venerable Sony notebook and a Dell desktop to Ubuntu GNU/Linux 10.10, with no issues.  No astonishingly obvious changes visible so far.  Gnome-Do doesn't seem to play with Docky; the Ubuntu Software Centre is a bit easier to use (but I don't use that very often); Trash is renamed "Rubbish Bin" in dialogues, but not on the desktop.  I dare say a bunch of other stuff will become evident in the coming weeks.