Donkey Lane and traffic jams

Why do people sit in traffic on the Calder Road when there’s an existing segregated cycle route from Currie to the Gyle?

When ‘almost’ is not much good at all…

Not far from our new house lies the curiously named “Donkey Lane”, a cycle path linking Currie with the Riccarton campus, Hermiston Gait and the Gyle, not to mention the west end and Lothian Road (via the canal).

Donkey Lane allows you to avoid the sort of daily rush hour traffic which I’ve attached in video for contrast. While you read this article, you may want to play that in a second window alongside (or if you really have the patience… it’s embedded below)

Now, back to Donkey Lane:

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The adjacent residential street, recently and extensively resurfaced…

Considering the huge queues that pile up every day along the A70 and down at the Calder roundabout, you’d think that this would be a popular facility- it takes me an hour to drive to our swanky office on the shore, yet I can bike it in roughly half an hour…

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Unfortunately most people don’t get any further than this – the entrance.

In reality, almost nobody uses Donkey Lane. So at least we aren’t alone there.

We house-shopped based on good school catchments with a linear segregated cycle route into town, so it’s a surprise to admit that we are driving more (vastly more) than when we lived in the south of Edinburgh in a flat which more or less pre-dated our interest in cycling.

Or is it?

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Donkey Lane is a public right of way but is in private ownership, and self-evidently receives no significant maintenance. In summer it’s horrendously overgrown, and for the other eleven months of the year it’s clearly a sort of linear swamp which can only attract the most dedicated masochist.

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There’s a serious upside to using these paths – it’s unusual for even one car to overtake me cycling between Currie and Leith, eleven miles away. And I’m saving 30 minutes each way over driving!

Unfortunately, after initial enthusiasm I have to confess that getting covered head-to-toe in mud and destroying hubs like they’re going out of fashion (despite full SKS guards) can get a little tiring.

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With the council looking to add 10,000 homes or so to this side of Edinburgh in the next few years, and constant hand-wringing over road capacity, you’d think paths like these would be massively low-hanging fruit.

On an average morning I can count a hundred cyclists between Wester Hailes and Leith on the segregated path network. If they all drove, it would be like one extra car every 20 seconds!

There’s only one cyclist who I see (on a blue moon) travelling via Donkey Lane, despite Currie having no shortage of well-off, well-educated people who are (for better or worse) the sort of people who seem to be candidate cyclists today. Instead they all sit bumper to bumper on the A70…

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There’s something of a heated debate on CCE just now about plans to properly surface a couple of East Lothian’s old railways, which has naturally been opposed by the usual competing interest groups.

No doubt the same argument can be made for Edinburgh paths like Donkey Lane and the Water of Leith – but we should be clear that we’re trading a lot of extra idling diesel engines to benefit a minority who prefer their paths filthy.

Cycling is itself a minority pursuit, so I suppose it comes down to whether we want to get people out of their cars at the expense of people like riding schools, whose horses understandably prefer a natural surface.

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You only have to stand on NEPN for a few moments to be passed by dozens of people who’ve left their car at home. Here almost everyone drives despite having a choice of segregated cycleways, because getting covered in mud (and needing expensive lights to avoid rocks and roots) is a hefty disincentive.

Does having a mud surface prevent speeding riders? Well, it is on Strava at 24mph… but would you rather have a 24mph cyclist on a deserted path or a load of 40mph drivers going past your local primary school?

Would you rather queue as in the video or have 10-20% of those vehicles cycling instead?

Evidently, it’s not enough just to have a muddy chute, because people aren’t going near it.

I raised this with our councillors and two of them were good enough to obtain a response:  “Donkey Lane forms part of the Council’s long term proposals to create a ‘family friendly’ cycle network across the city and we plan to focus on its development once the shorter term priorities have been delivered”.

I’m not holding my breath, considering that it took ten years from the Land Reform Act to sort out the *signage* for cycling in the Meadows… but I am looking forward to getting back out of the car some day. 🙂

ICE VTX Review

The new VTX is the top of the line racing trike from ICE. Just how good is it?

Hold on tight: the best just got (much) better

At first sight of the marketing blurb which accompanies the VTX I was sceptical. “It looks much the same as the Vortex to me,” I thought. “Beyond a few cosmetic tweaks to make it seem worth the upgrade, will there really be much difference?”

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I must admit that I wasn’t completely convinced by the ICE Vortex – a trike so uncompromising that I had bruises over my vertebrae after just a few hours hard riding. Sure, it was fast (for a trike), but given the type of roads I have to ride on, I couldn’t really imagine owning one.

I’m happy to say that my suspicions were completely wrong. While evolutionary, ICE have made a very significant upgrade in the VTX – no less of a speed demon but one which is significantly easier to live with.

I’ve also been able to take some power-based performance measurements for the first time; scroll down for details.

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All change at the back

The headline upgrade comes in the form of the new rear frame section, which employs hydroforming in an attempt to create a more compliant ride, without sacrificing drivetrain efficiency or cornering performance. The seat bracket has also been relocated to further reduce the transfer of road impacts.

I deliberately took the VTX for a session on a local tarmac road which has started to fall apart, and I could hardly believe the difference – despite rattling at full speed over inch-deep cratered moonscape, I still felt pretty comfortable in the seat and the trike was easy to control.

On my maiden ride with the old Vortex I had to stop every five minutes to tighten something… was this my first hint that the VTX was actually a step-change? No – I was convinced of that immediately.

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Handling

The ride quality of the VTX is head and shoulders above anything else I’ve tested. The whole trike feels beautifully poised, and can be flung around the road with one-handed abandon.

Conducting virtual elevation tests one frosty morning (where braking is an absolute no-no) I found the tail drifting out on the sharpest corner and it was no worse than entertaining. I settled for imagining I was Steve McQueen, started pedalling hard and everything eventually straightened out!

Speaking of brakes – as with all ICE trikes, brake steer is non-existent on the VTX (we live on a steep street, and I took the demo to skidding point with one hand without the slightest inclination to pull to one side).

The whole trike feels incredibly refined and leaves you in no doubt that you are riding a top quality machine.

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Power tests

I decided to take a different approach with the VTX and perform some virtual elevation testing to measure its performance. See here for an informative PDF by Robert Chung.

The general idea is that if you know CdA (aero resistance) and Crr (rolling resistance), along with weight, air density and so on, physics will tell you *exactly* how fast you will be going for a given power input.

If you compare this theoretical speed with actual speed and it turns out you’re going slower, the only answer is that you are going up hill (and vice-versa). A virtual elevation profile can thus be drawn up by charting these deviations in speed as changes in height. You have to do some guesswork with the CdA and rolling resistance until the virtual profile matches the real altitude profile, but then you’re done.

Unfortunately, having the trike for weeks which turned out to be some of the wettest and wildest on record made it difficult to gather a compelling set of data due to wind interference (wind slows you down, which looks like you’re going uphill).

However, with that caveat, I came up with the following approximate values: CdA: 0.350, Crr: 0.01

(Note that the trike and my body / clothing are indivisible, and the rider makes up a good chunk of the above figure!)

I performed a series of laps in a built-up area where only one leg was exposed to a (very light, almost un-noticeable) headwind. I was able to create the expected virtual elevation with the above values:

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Obviously, the altitude increases with each lap, but the thing giving me confidence is that the profile is exactly correct on the three sides which were sheltered from the wind. The one wind-impacted street (which connects the descent with the start of the next lap) slopes down in reality, but doesn’t slope down enough on the VE chart, due to the headwind making it slower, thus “flatter”.

It’s pretty interesting stuff. I rode the laps at differing speeds, and it looks like you can see the trike scrubbing in the hardest corners (as it slows me down, it makes the elevation a little steeper than the road really is, giving some variation in the exact profiles).

I was almost out of good weather, but had one opportunity to validate these numbers by climbing a local hill between two spot heights measured by Ordinance Survey. As you’d hope, the virtual height I climb to in the plot below (blue line) ends up at *exactly* the expected height (denoted by the vertical green bar at the finish, which is neither too high or too short to meet the blue line):

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If I’d been thinking ahead, I would have climbed the hill several times at different power to further validate the figures, but it was just a snap decision when I happened to be there.

Just to point out – the blue line above is completely synthetic based on Watts at the rear wheel and estimated Cda/Crr numbers. My power varied plenty on the climb, and yet the plot captures the ramp up then steady gradient which exists in real life. Neat.

Knowing the ballpark CdA and Crr allows a direct comparison between the VTX and other bikes/trikes without arguing over routes and weather conditions. For a great example, refer to this post by techathy on BROL, plotting the Vortex against the Challenge Fujin and a regular time trial bike.

(I believe his Vortex has a aerodynamic tail of some sort, so as expected it’s a little more streamlined than the VTX was for me.)

As you can see, unfortunately the VTX isn’t as rapid as a time trial bike, let alone a lowracer. But on the other hand, you can’t spend much time riding in the TT tuck (certainly not an entire leisure ride) and if you do, you can’t see much of what is going on. The VTX is extremely comfortable and you can look around 🙂

Note the significant difference in speed at 200W and above – 4mph slower than the Fujin or DF time trial bikes (but “only” 2mph slower than the more common DF ‘hoods’ position).

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Contrast the profiles of the VTX and the Sprint 26X (with extra laid-back seat!) – from the Laid Back Flickr stream

I was asked specifically to compare the VTX to the Nazca Fuego, a low(ish) and not insanely reclined two-wheeler. My gut feel is that over mixed terrain the Fuego is faster, but the VTX is close, unlike the Sprint or Adventure – the VTX is a similar weight and the drivetrains are not dissimilar in perceived efficiency. When I’ve been able to perform virtual elevation testing with the Fuego I’ll produce a specific article on this, but for now, I’d say anyone swapping from a non-racing two wheeler to the VTX won’t be overly disappointed…

Construction in detail

Much of what I wrote in the Vortex review applies equally to the VTX, so that may also be worth your time.

To allow for a lower and more reclined seating position, the VTX continues the set-back seat position of the Vortex, and this can make it slightly more challenging to get into. For the vast majority of prospective owners this is just something you’ll get used to in a few minutes, but I was reminded of it repeatedly whenever someone wanted to sit on the trike and see what it felt like!

It’s hardly made of paper, but a heavy enough collapse onto the seat (especially if you took the carbon option) might not be the best idea.

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The VTX is fitted as stock with a triple chainset (compact double on the VTX+ for the mountain goats), and although I hardly used the smallest ring, you should be aware that the 700C driving wheel is so much bigger than the 20″ drive wheel on other trikes that it makes each chainring the equivalent of the next size up.

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In other words, the small ring on the VTX is like the middle ring on a Sprint 20, and the middle ring on the VTX like the big ring on a Sprint 20 – so with the VTX big ring, the sky’s the limit!

(Unfortunately you still have to pedal 😉 )

Below is a close-up shot of the new rear frame member. It’s fully rigid and the tubes are highly profiled and bowed to improve comfort and handling. Note the upper seat mount is just visible right up next to the power idler – nowhere near your shoulders, and the difference is really dramatic.

Note the fine detailing around the dropouts, which have been extensively relieved and look fantastic.

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Here’s another view. You can see that this model came fitted with a rear mudguard. The month I had it prior to publication was the wettest December since records began and I doubt I would have ridden at all without it!

By way of contrast, the lack of front mudguards will only get you wet if there’s a cross wind at just the wrong angle to steer the spray into your path… a compromise that seems worth making to avoid increasing the VTX’s frontal area any further.

Note the new headrest. Even that is a significant step up on the Vortex (i.e. I actually used it from time to time!)

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The new seat pad is excellent – my back didn’t feel at all sweaty even on the hardest ride (note, it is winter at the time of writing so not the sweatiest time of year!)

Most importantly, the seat holds you securely when corning hard and it stays comfortable even when you’re being pounded by a broken road. A great improvement.

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Front of house, the VTX comes equipped with the ubiquitous BB7, made razor-sharp by the tiny length of the cable run. Braking one-fingered is natural… quite a revelation compared to my grimy collection of well-used winter bikes!

The VTX+ has an upgrade to hydraulics for minimal maintenance and even greater bite (though you have to wonder who would find the brakes on the base model inadequate…)

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The handlebars and stem come in one piece – this makes them light and stiff, but I suppose may not suit every rider. Personally, I kept rubbing the mirror t-bar extension off the tyre when cornering in tight spaces… user error?

The shifters are SRAM and work crisply and flawlessly – shifting on the VTX is instant as you’d expect from anything which costs as much as this. Just be aware that as with the original Vortex, adjusting the boom will throw off your front mech completely, because the gear cable runs to the boom without an outer housing.

The rear mech had an amazing feature where you could push in a pin to lock out the spring and work on the drivetrain (or remove the wheel). This blew my mind and all my SRAM rear mechs are now destined for upgrade-land…

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The VTX (reviewed here) doesn’t have quite the same quality of finishing kit as the VTX+, but I’d be amazed if anyone took it out for a spin and felt dissatisfied: every detail has been attended to and as a complete package this is one of the sharpest rides in town.

Conclusion

Speed-wise the VTX is streets ahead of any other trike I’ve ridden, and should not disgrace itself in the company of two-wheelers if you normally ride strongly. That said, the inherent penalties of multi-track mean that it won’t leave any two-wheeler in the dust, either. In return you get an insanely fun machine to ride, given twice as much space by passing motorists, and everything else that’s unique about trike riding!

As always, I haven’t talked about price. While it’s a fact that the VTX is significantly more expensive than some other trikes, there’s no question you are buying a quality machine.

The handling is perfect, the seat very comfortable even after many hours, the complete package is light and has excellent finishing kit… it really is quite easy to recommend. ICE have little to fear when it comes to losing their crown.

There’s a demo currently available at Edinburgh’s Laid-Back-Bikes, but I suspect it won’t hang around for long!

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