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25 Jul 2011

Coroplast 'shorty' TF

My Pioneer is a great 'bent. It does just about everything. That's the reason I choose it to ride to Spezi with. For longer distances and headwinds there is a problem though, it's not that fast. Compared to what I'm used to, what my 'standard' is, it's slow into a 4Bft. headwind.

Coroplast is a nice material, but almost completely unknown in the Dutch recumbent world. In the English speaking world, it's used quite often. On the CV2011 campsite, my tent was pitched near Fards' tent. And, one we the things we talked about, was the 'magic' material. I'd already found a Dutch website selling it, but during CV the decision was made that I'd do something with Coroplast. You could say that Fards ignited this project.

First I thought making something for the Q451. However, that already is a quick little bike. The Pioneer is the bike that could use less drag. I ordered several sheets, and tried to think not too long about the high shipping costs of the large sheets. I know had them in black, which looks cool.

First I made a cardboard template for the back panel and the floor. The floor would rest on the luggage rack. The back panel would have a widest point of 46cm, matching my shoulder width. I cut the panels and bent flaps under a 90 degrees angle, using a hot air gun. Pop rivets with little washers kept it together. Than I could add the sides and cut those to size. I lowered the stress on the joints by heating the curved surfaces. The edges where sealed with Tesa Power Tape. You can also use hot glue to join it.

It looks alright, not a pretty one, but stalwart. It held in place with only 2 bolts, near the bottom of the seat. I kept it relatively short in order to make it easy to store in the shed. Normal sized TF's are sort of bulky.

The first thing I noticed during ride number one was how silent it is.The first ride was to the hairdresser, so I didn't do any tests regarding the aerodynamic qualities. It did give a hint of an advantage.

That evening, I went out for a ride. Curious about how good it would be and just to ride. After 15 minutes or so the idea came to do a simple roll out test. Here's what I did on my test location.

  • accelerate to 40kph
  • coast down to 30kph
  • measure how long that takes in seconds
  • 2 times, return run, that's 4 runs
  • repeat without TF.

The method is not very precise, not at all. But, the results, which I had to memorize, where clear and consistent enough to conclude that the TF really works. Without the box, it takes about 11.5 seconds to get from 40 to 30. With box, it takes about 13 seconds. If I than hustle the results a bit, trying to be as negative towards my own design as possible, the TF gives at least a 7-8% advantage. And for such a short TF, I find that's very good.

When I rode to work last Friday, the advantage was very welcome. A strong head/side wind, and still I could keep going at 29kph or so. For less than €30,- and a short day of work, I'd made my big practical Nazca significantly faster.

19 Jul 2011

Group ride at night

Last Friday I travelled down to IJsselstein. After work I rode to Meppel, took the train to Utrecht, and cycled the remaining 12km on my Pioneer. My Garmin Dakota knew how to get there. It turned out my destination is marked quite well. It's close to a 300 metre high radio tower. Speaking of radio towers, on of the first things I heard when I arrived at Maarten's place, was that 'my' radio tower had lost 200 metres.

The tower of Hoogersmilde. I ride past it so often. It's still there, but the top has collapsed. A fire caused the metal antenna to melt, snap and collapse down in to a field. That tower has been my source for FM signals all my live. Now, it's future is uncertain. The 100 metre concrete part is still there. With a little luck, that part is good enough to mount a new antenna on. We now miss a land mark and an icon. Listening to radio 1 and 2 can be problematic. And those are about the only stations I listen to. I dedicate this song to the tower of Hoogersmilde: Radio Gaga.

Back to the ride. Plan was to ride near the Lek river. Not before the sun had set, and we had something the eat. Maarten and Maaike had prepared ingredients to mix your own pasta salad, jummy. We left around 22:20h.

Since the invention of the high power LED, riding at night has become a relaxing experience. Navigation was easy, just follow the Gaucho. To my surprise, the headlights gave enough light for my camera to film some of the ride. We enjoyed the scenery and chatted a bit. There was a full moon, and every now and then, the clouds would move aside to show it. The temperature was right, the wind hardly there. Only downside was the length of the ride, just under 50km. Not really a problem of course, I just felt good enough to do more.



Afterwards there where waffles and hot chocolate. Both with whipped cream :-) And tea too, so plenty of fluids after a day total of 108km. The result of all this hospitality was a bedtime of 3 o'clock in the night. I slept 'till 9.

Breakfast was followed by a bit of music. Songs about tea and silver machines, subjects well known to many 'bentriders. I also did a little work on a Fuego and a Pioneer. By now it was almost noon. And I still had quite a ride to go. So I loaded my stuff in to my Radical Backbone, and said goodbye.

There was a 180km ride ahead of me. But the short night and my right ankle limited me in my performance. On Sunday I did some measuring and concluded that a reason for my ankle problems is that my feet are a bit to far away from each other on the Pioneer. You have time to think when you ride 185km in 2 days time, and I used some of that time to think about my right ankle. Now, if you paid attention, you now found out that I only rode 77km on Saturday. That's because I took the train from Putten to Assen. It had started to rain and I didn't feel like draining myself empty on 180km. That did cost me some money for a train ticket, but I arrived home feeling fit. The last 3km from the station in Assen to home where fun again.

A bike like the Pioneer is excellent for riding through town, on not so good roads, with quite some speed. The fat tires and rear suspensions soak up the bumps. And even though it rained, those 3km where fun.

10 Jul 2011

Das K, Probefahrt

Yesterday I took the 6:55am train to Venlo. I'd made an appointment with Beyss, the manufacturer of the Evo K in Straelen. The public transport did it's job well and I arrived in Venlo without any delay. From there, it was a short ride with my Cruzbike to cross the border with Germany and arrive at the Zeppelinstrasse.

I was very much on time. After 20 minutes or so, Daniel Fenn arrived in a K. After he had a close look at my Q451, we set up a K for me. Kojaks on the front and some foam to lift the seat a bit. I used the seat covers from my Cruzbike in the K for some extra comfort, and to be able to see the road in front of me.

As soon as I'd left the Beyss factory I tried to find some bumps in the road. Those bumps aren't much softened by the suspension. The good thing is that the K keeps on going in a straight line, not affected by the bumps. The seat covers made it all comfortable enough. Because of the supreme build quality, the body does not rattle at all. The noisiest thing is the rattling freewheel. A 23t TC idler under the front tip op the seat guides the chain to the rear wheel.

Getting used to the side stick steering would probably take a few hundred kilometre. But even so, I felt quite confident at 50kph, with a strong wind from the side. Achieving that same speed with a headwind was as easy as pie. Slowing down with the independent front brakes felt secure. That said, the high speed potential of the K does make me advice 90mm drums, instead of the standard 70mm.

To test it's usability on roads of lesser quality, I used some German urban cycle paths. It manoeuvres nicely, though something narrower than 35mm Kojaks on the front is wise. Minit's Tough could be perfect. There almost as wide, but significantly lower, giving you a smaller turning radius, which is a good thing.

I even found a tiny elevation. With it's super stiff construction and weight of only 18kg, this must be the best climbing velomobile on the market. You would need more than the 1x10 gearing that this K carried. A 38 and a 63 on the front, combined with a 12-27 on the back would make it more pleasant in every day life. A long cage derailleur could do that. A 63 combined with a 559 rear wheel, may sound odd, but with that combination, I'd often be cruising in 6th gear.

So, it's actually pretty good for normal use. Are there downsides? Yes, some. The rear wheel is not single side mounted. That makes the construction a lot stronger, but fixing a flat would take more time. Extras, like lights, indicators and rear suspension cost a lot. Luckily, vm electronics are not that complicated. The openings on the left photo can easily be closed with fibreglass sheets and magnets.

It's not perfect, but nothing is. The ride is divine, the quality outstanding. The K is wickedly fast and looks fantastic. With a few easy and small changes, this could be the best VM for a velonaut like me. In the more affordable 23kg version that is.

After the ride, we had some coffee, discussed my experiences and wishes with the K, and I got a factory tour. Daniel showed me the differences between materials and we put a few items on the scale. I saw rear forks, weighing around 400 grams. A set of rear drop-outs, weighing 30. And, very interesting, we testes a Milan entry hatch. This one had some cosmetic damage, making it good for a smash test. It was hit with a steel pipe, the size of your arm.  You can find more photos in this Picasa album.

After 4 interesting, fun and possibly, in the near future turning out to be expensive hours, I rode back to Venlo. Again, my little Quest surprised me. A small hill was easily climbed and descended without any hesitation. Manoeuvring  through an unknown city with several diversions, while looking at a GPS, was no problem. I believe I dreamed about the K in the night that followed.

Two days later, I took time to create a short video.