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Plans for Moz's second Kotzur Bike

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clockwork banana I have decided that I "need" a new bike, and that I don't want to build it myself. What I want is pretty much s 20" wheel low recumbent set up for commuting but that can be used for touring as well. The Clockwork Banana that Wayne Kotzur built for Ken Rubeli seems to be a good start, but naturally I'll need to make some changes.

After touring Western Australia on the tandem trike I decided that for touring trikes are a little bit too much like hard work for my liking. Just pushing three wheels seems to be harder than strictly necessary, and this was reinforced by a couple of people I talked to who had nice new Greenspeeds to tour on, so it probably wasn't just my bad design.

I sat down and thought about what I want, as I do. Rather than go into the huge detail that I had for the tandem, here's a summary.

Wheel size The front wheel of a recumbent bike really needs to be 20" or less, and for touring having one tyre size makes life easier. So 20" wheels both ends it is, even though that makes gearing slightly harder. If possible I'll get the rear wheel built non-dished to give a little more strength.

Bike design I like the SWB design , and under seat steering for touring. But for riding in traffic above seat steering is much better. Fortunately Wayne offers both and you can swap (provided you get the fittings for USS to start with).

Seat angle After riding my first Kotzur bike for a while I decided that a 40° seat is too steep, so I put 30° seats on my tandem. While in Perth I rode Beatrice which has a 30° seat angle. I could ride it, and I think I'd like it.

Suspension Obviously essential. My first Kotzur lacked it and I think that it's pretty important for touring on less than perfect roads. Wayne has also come up with a pretty nifty way to put elastomer suspension into the rear wheel, so naturally I have to try that. It gives a centimetre or so of travel, just enough to even out a bit of road noise. As a bonus it can be used to fold the bike up if required. Perhaps this one will go into a suitcase (if I owned a suitcase).

Brakes I used Hayes hydraulic disks on my tandem, and after 6 months I begin to see why I had so much trouble finding people who'd maintained them. I asked probably 30 riders who had Hayes brakes (by stopping them in the street) about how hard maintenance was on them. No-one knew. And now I know why - you don't maintain them, they just keep working. Oh, and they also work better than any rim brake I've ever used. So the new bike has to have hydraulic disks. Since I have a spare Hayes front disk (bought it in a sale, you know how it is) I'm going to get another one and that way have some redundancy (if the front brake does fail I can swap the rear in and still have one brake, but at least it's on the front).

Gearing After having the disks I'm becoming attracted to low maintenance systems on the bike. So because I can, I'm going to try a Rohloff 14 speed hub gear on this bike. If necessary I can go back to using a 9 speed derailleur system, the rear wheel off my tandem should be compatible with the bike. Although the lack of a front derailleur post might be a bit annoying, but I can always use a Mt Drive or get a post added if it comes to that. Unlikely I think.

Racks When it comes to loading, I'm a complete idiot. If I can lift it, it goes on. Much like Evan, who rode 5000km with probably 60kg of gear on his bike and added Antionette on the back at times. I like Evan's under-seat rack, but it is a bit hard to get stuff out of the middle section so perhaps similar but not identical would be better. And Evan kept breaking spokes, I think because of his dished 26" rear wheel. Another reason to get a 20" one. I'm sure Wayne will understand.

When Ken toured NZ with Owain, Owain had a new TriSled bike. This has a pretty wide rack (250mm or so) and gave huge air resistance problems because Owains panniers stuck out and up well outside Owain. I'm pretty convinced that I want to fit a tail box to avoid that, but also that I don't want a wide rack since I don't put boxes on top of it. So perhaps go the other way, and have a tapered rack the width of the rear axle at the bottom but only just wider than the tyre at the top. To make things more compact, I'm also thinking of making the rack integral with the rear triangle, so that it's unsuspended.

Trike and trailer with furniture
carrying stuff

Evan's bike loaded up
Evan's bike

rack plan Drawing details
Blue lines are the rack, the rest is bike bits.
A: seat back
B: suspension pivot
C: suspension elastomer
D: pannier support loop
E: light mounting bracket
F: note narrow spacing between rack and 50mm tyre.
Numbers are the mounting points for the tailbox which I want to build later.

Ortleib front pannier sitting next to my Trisled Panniers I use some yellow homemade panniers that are similar to Ortleibs but slightly larger and without the tendency to fall off the bike that Ortleibs have (Hint: if you own Ortleibs, buy a second set of clips for each one and install them. Four clips per side will work, it's what I used on mine for 5 years before I sold them). Anyway, the rear panniers are fine and should work with the rack idea above, but what about moving weight forward? The banana picture above shows precious little space for that, but I'm taller than Ken so the bike will be longer and should be able to fit a bag between the wheels. I'm keen to just have hangers there and tie one of my Ortleib front panniers under there, rather than having a rigid rack. By putting a couple of D rings or something on the front of the seat I should be able to hook the pannier on, then use a strap to hold the back of it up. That gives me under seat storage (USS) for very little weight penalty. If it works. The picture was to give Wayne dimensions for the pannier.

Tailbox I intend to build a hard-shell tailbox at some point to reduce air resistance and also make touring easier. Why use panniers when you just have a big bin on the back of the bike? Initially I plan to make a coroplast box for the bike, but once that shape is right I'd like to make something out of stronger plastic or fibreglass that I can use instead of panniers. It will need to be waterproof but that shouldn't be too hard I hope. A tailbox gives a couple of kilometres an hour of "free" speed if the experiences of Tony and Ian are anything to go by.

Lighting The advantage of a bike is that I can get a dynamo hub. So I'm going to try it. Evan had a Schmidt hub on the WA ride and it worked really well. Schmidt's homepage is in German only, www.nabendynamo.de but there's some good info at www.peterwhitecycles.com in English. I like the idea of two 3 Watt lights on the front so might try that. Right now I'm infatuated with the new giant bike lights I found at Jaycar, same price as a standard LED bike light but about 5 times the size. 18 LEDs, 4 AA batteries and it's BRIGHT! They're about 170mm long by 100mm high.

Steering One problem I had with my last Kotzur was my tailbone hitting the steering pivot. It stuck up a centimetre or so above the frame tube, and my tailbone stuck downwards. This also ties into wanting to sling a pannier under the bike as Evan does, but without compromising ground clearance or seat height too much. Perhaps making the pivot attach to a flat bit of steel that sits on top of the frame tube, then attaching the bars under this might reduce the space used. The other issue Evan has is that he keeps breaking handlebars. With USS you can either have short straight bars that really are under the seat, or curved bars that go out and up, but are then the widest part of the bike and also what it falls on if it falls over. Making the flat plate out of spring steel and using CroMo tubing might help there, but I'll have to see what Wayne says to the idea.

Transport Packing the bike up into a bike box needs to be possible, and ideally should be doable using touring tools in an airport or bus station. If the seat is removable then the whole bike should easily go into a bike box (including one or more panniers) which is ideal. Without much gear I expect to be able to pack it down more, perhaps even to suitcase size if I ever feel the need.


Tony and Ian's Tailboxes

These two commute from Newtown to Paramatta every day, much as I used to do. Ian has a SWB ASS recumbent, and Tony had a mountain bike. Since Ian is considerably fitter than virtually anyone to start with the extra advantage of the recumbent was a bit over the top. So Tony bought a recumbent from Ian, and soon decided that he needed a tailbox. Ostensibly for the HPV races that were coming up. But once he had it on the bike Ian pretty quickly noticed that it gave Tony a definite advantage. Rather than being a couple of kph slower that Ian, Tony was now a couple faster. Something must be done!

These days you can see two guys with short wheel base recumbent bikes and tailboxes riding to Paramatta most days of the week.