A noobs guide on how to (not) build a cargo bike

I live in Norway, a country best known for getting filthy rich by selling filhy energy, and for polar bears roaming the streets. The latter is mostly a myth, but the winters can get quite harsh, and winter tires are mandatory. For cars by law, for bikes by necessity.

Clawed paws, spiked tires. Photo: Wikimedia Commons

I commute by train and use a Brompton folding bike for getting to/from the station in both ends of the train trip. For those familiar with it, the Brompton is a lovely bike, in particular when folded up behind the train seat. It’s a great ride on paved roads and extremely nimble in the city. On icy dirt roads in pitch dark, it’s another story. The only spiked 16" tire available is the Schwalbe Winter HS396. Big thanks to Schwalbe — it has made it possible for me to turn my Brompton into an all-year bike, saving bundles of time.

Unfortunately, the tires must be inflated to 5+ bar in order to (hopefylly) avoid having the spikes work their way through the inner lining. And riding on a sparsely spiked 30–349 tire at 5.5 bar on bumpy ice is not a great experience, put mildly.

My Brompton in it’s usual winter maintenance mode — awaiting a new tire.

I also don’t drive a car. Living in a small town where there’s at least two cars parked outside of every house, most people probably think I’ve committed some severe traffic violation and lost my drivers license permanently. Truth is, I don’t feel like getting it, and egoistically leave all the driving to my wife.

What it all boils down to is that I’m an all-year transport cyclist and I frequently need to carry stuff, be it two cartons of milk, or a 10" miter saw. The Brompton is simply no up to the task, especially during winter — I need something robust, with a medium/large cargo capacity, more riding comfort and better winter handling.

I started looking around, and quickly got pointed towards the Cargobike Magazine. Here I found an article on Sverre André Muldsvor’s endavour with a modified Surly Big Dummy, a Surly Bill trailer and a pile of logs. I also looked into a few alternatives, such as Benno Bikes Carry On. While truth to be told the latter is probably a better fit for me, its smaller wheel size means the selection of winter tires is less than great. And.. well, I now have better understanding of men buying big, black SUVs with oversized tires.

The Land Rover of cargo bikes. Photo: cargobikemag.com

Anyway, quickly found that Oslo Transportsykkel sell the Big Dummy, and popped by to get one. Alas, even their demo bike was gone long time ago. Late November is not the best time to go shopping for new bikes. But elsewhere I was told that Big Dummy frames could be ordered from abroad, and I could then assemble my own bike. But there’s no way.. I don’t have the time, the competence, the workshop and so on. Dumb idea — forget it!

Instead I started reading Cargobike Magazine again, drooling at all the cool bikes and nifty solutions. Until, pretty deep down in their archive I stumbled across an article about Per Bjarne Løvsletten who built his own Big Dummy from scratch. Just for fun (I think), I started making a list of all the components I would need to buy. Originally this was defined as “needed in order to make the bike roll, and that I could not strip from another bike I owned”. During the process, it transitioned into to pure “want”. This involved a lot of rationalizing, of course. Like “€200 is a really good price for a hand built Mavic XM 719 with a SON deluxe dynamo hub”, and “if I have Mavic on the front wheel, I should probably have Mavic on the rear wheel too”, and “since this is already getting bloody expensive, I might as well get the Brooks saddle I always wanted”.

The saddle of your dreams for the bike of your dreams. Photo: cargobikemag.com

I don’t have a lot of experience with bike buiding, and what little I do have is more than a decade old. Using the above mentioned article as a guideline, in particular the claim that Shimano SLX is good value for money, I started trawling online stores. Mostly Bike24 because their user interface sucked the least. After a short week of reading and browsing, I ended up with the following list. I’ve included links, enjoy them while they last, but don’t assume this configuration is a great one (or even compatible):

  • Surly Big Dummy 20” (large). I’m 180 cm, pretty reguar build, so I’m hoping it’ll fit me.
  • Brooks B17 saddle. I always wanted one for my Brompton, but it’s original saddle seems to never wear out.
  • SR Suntour NCX seat post. I haven’t made up my mind on whether to try it myself or give it to my wife for christmas. In case I go for the latter option, I also got a soft spring for it.
  • Shimano XT BB-MT800 bottom bracket. A cheaper one would probably do, but it seems like a silly place to save a couple of euros.
  • Shimano Deore FC-T6010 crankset. I originally went for an SLX crankset, but just before placing the order, I noticed that it was a Dyna-Sys crankset. I had never heard about Dyna-Sys before, but after a quick search I found that it is likely a) good and b) incompatible with non-Dyna-Sys components. Rather than trying to upgrade all the other components I changed to a different crankset. However, this incident makes me wonder how many incompatibilities I didn’t discover before ordering. I sense heavy cursing ahead…
  • DMR V8 pedals, hoping Per Bjarne knows more about pedals than me. Also, they appear to be ok to use barefoot in case I want to do that. In retrospect, I can’t think of any situation where I would want to ride barefoot, but I know for a fact the the pedals of my pub bike doesn’t work barefoot, so at some point I must have tried.
  • Shimano CS-HG50 11–36T ten-speed cassette. In retrospect, I could probably have used an eight-speed cassette which is cheaper and is supposed to be more rugged. Oh well; that’s pretty easy to change later.
  • KMC X10–73 chain because it was what Surly uses. I bught two, of course, because of the length of the Big Dummy.
  • Shimano SLX dual pull front derailleur. There are so many variants of front derailleurs these days that it made my head spin, but I think this top-swing, dual-pull, low-clamp variant will work.
  • Shimano Deore XT Trekking rear derailleur. This is a tricky one since most rear derailleurs these days seems to have the cable entering on top, and this supposedly won’t fit the Big Dummy. I’m not 100% sure this one has the old style cabling, but from pictures of bikes claiming to use it, it seems so. Fingers crossed, since this is a relatively costly component.
  • Shimano SLX B[LR]-M7000 brake handles, calipers and hoses. I don’t know much about hydraulic disc brakes. Hopefully they’ll fit, or I can get an adapter. Otherwise, this could be an expensive mistake.
  • Shimano SLX SL-M7000-IL front shifters and Shimano SLX SL-M7000–10-IR read shifters. These are supposed to be mounted on I-Spec II brake handles.
  • Shimano Optislick gear wires. These are a little more expensive than what I’d normally get, but the Big Dummy is longer which means more friction, so extra-slick cables seems to make sense.
  • Shimano OT-SP41 cable hoses, because they come in green and Shimano SIS-SP40 end caps because.. I got carried away and it’s only another few euros.
  • Knog Oi Bell looks awesome and a lot more rugged than the average bell.
  • Busch + Mülller Cycle Star 80 rear mirror looks functional. I haven’t had a rear mirror before, but for a pure transport bike it makes a lot of sense.
  • Busch + Müller Lumotech IQ front light. Busch + Müller offer a wide variety of lamps, and they are supposed to be good quality. They have so many models that I selected this one in desperation more than anything else. It has many luxes and looks ok.
  • Busch + Müller Seculight LED rear light was easier. This one seems to attach to the mud guards, which should be safe enough.
  • On-One OG handlebars was recommended in this article by Cargobike Magazine, and it doesn’t look as extreme as the Jeff Jones H-bar I was originally looking at. It’s also 1/4th of the price, and a colleague of mine can mule it from the UK for free.
  • Stronglight RAZ headset because it’s cheap.
  • SKS Buemels muduards, the widest they’ve got.
  • SON deluxe | Mavic XM 719 front wheel was on sale and cost about the same as the hub alone. I planned on getting a Shiman Alfine and a cheap SUN rim, but it’s hard to pass on such a good offer (and saving a lot of wheel building work). It only has 32 spokes, but I recon that’s going to be good enough for the front wheel. I could have saved a lot by not getting a dynamo hub in the first place, but since I ride a lot when it’s dark I figure it’s money well spent.
  • Mavic EX 729 rim and Deore XT M8000 hub for the rear wheel. This will become a 36 spoke for a whopping 12% more strenght (cross three). I doubt it will be needed, but it won’t hurt either.
  • Schwalbe Ice Spiker Pro winter tires, in the unlikely event of completing the bike before the winter is over. They look fat and pointy, which is just what I want.
  • Shimano SLX SM-RT64 203 mm brake discs. According to the Surly docs, this should be supported, but I’ve heard claims that 180 is max in front or else you risk breaking the front fork or wheel bolt. I’m not too worried. If I ride a fully loaded bike, I’m going to be darn careful anyway.
  • Surly Big Dummy Cargo Kit panniers and mounts. I haven’t really looked into this yet, but a Big Dummy without panniers is pretty useless, so getting this is a no-brainer. I probably need more stuff, like wideloaders, but that can wait.
  • VeloPlugs Rim Plugs instead of rim tape for the rear tire. Never tried them, but I like the idea.
  • KLICKfix MiniMount because I probably need to mount the front light somewhere vertical.
  • Hebie Steer Damper 695 to make the bike more stable when loading it. I’ve never tried a steer damper before, but I’ve heard good things about them.

Besides this, I also have or is planning on getting/making the following:

  • A sturdy bike needs a sturdy lock. I have an Abus Granite X-Plus somewhere from back when I lived in the city. I also have the keys, probably somewhere else.
  • I have a cheap, adjustable stem which I can probably use, at least to start with to find a good angle.
  • Brooks has nice leather handlebar grips, and I’m toying with the idea of somehow making this myself. We’ll see.
  • Brooks also has leather mud flaps. This is bacially only a thick leather rectangle with a steep price tag, and I recon I can make one myself.
  • I spent some time researching the propstand options, and it seems Big Dummy owners either spend a hilarious amount of money on Xtracycle or Rolling Jackass stands, or they simply “lean it on the wideloaders”. Then I found an article from a guy that used a pretty generic cast aluminum propstand and even preferred that over the Xtracycle center stand. I happen to have one which I stripped off my Easy Racers Tour Easy a while ago, so I’ll try that.
  • I really want a front rack, and considered Surly 24-pack, Gamoh KCL-3F and various Steco models. In the end, I figured this can wait a bit. The same goes for the front basket, where again Cargobike Magazine provides plenty of inspiration.

As mentioned, I’m not really competent to build this kind of bike from scratch, so the above list probably contains plenty of mistakes and omissions. I’ll try to follow up with one or more posts from the assembly process. Read that for advice on how to not build a cargobike!

The orders were placed on November 30th and should ship in 3–9 days depending on availability. With a bit of luck, everything will e here in time for christmas. The front wheel was out of stock the next day, which makes it feel even more like a bargain. :-)