Friday, 6 June 2014

Frankenwheel

I do a fair few miles per week, averaging around 160 miles, with most of those done on rural lanes. Now some lanes are quite good, but others are in shocking condition. All rural lanes are often debris-strewn, especially in winter. As a daily cycle commuter, cycling to work and back in winter, more often than not is done in darkness, and though I have a 1000 lumen light, it is still easy enough to miss a pothole or other obstacle, particularly if it's raining.

Because of all this, as you can imagine my bike takes quite a beating and my bike's wheels bear the brunt of that.

I've been riding a B'Twin Triban 3, which is a brilliant bike and an amazing bargain. I had problems with the stock rear wheel - after only about 1 000 miles the bearings were shot and I was sent a replacement wheel. This wheel lasted around 750 miles before the same thing started happening and I ended replacing the wheels with Mavic Aksiums.

The Aksiums were brilliant, although you have to keep on checking that you don't have spokes that worked themselves loose. Despite this need for regular tweaking, I was still impressed with the Aksiums. One downside to them is the lack of wear indication groove on the rim, and I wore the front rim through in about 9 months.

That is VERY quick to wear a rim out, and left me less than impressed. The end result was that I put the stock front wheel back on the bike.

I had a chain snap on the bike, and it wrapped itself around the rear derailleur, bending it into the spokes of the rear wheel and resulting in a rear wheel lock, with part of the derailleur being sheared right off.

After having replaced the chain and the derailleur, it wasn't long before the first spoke on the rear wheel snapped. This spoke was damaged by the sheared off derailleur and I immediately ran into an issue: nobody stocked Aksium spokes. These are bladed spokes and are very different to normal spokes. Normal spokes don't fit the Mavic hubs. This meant I had to use a different wheel, while I waited for the Mavic spokes I ordered to be delivered.

I took the rear wheel from my hybrid and fit it to the bike, then replaced the broken spoke when the packet of spokes arrived. After trueing the wheel again, I was good to go. The thing is, the Aksiums only use 20 spokes per wheel, so if one goes the wheel warps quickly.

A week or so later, another spoke broke on the rear wheel, this time not on the drive side. I had no spares, so removed one from the failed front wheel. The following few weeks saw a few more spokes snap, on both sides of the wheel. One spoke, after snapping near the hub, got caught in the chain and sheared out of the hub. This was some 15 miles from home, and I limped slowly home on a pringled rear wheel.

Of course, I had a new bike on order, but as per sod's law there was a delay at the factory, so I had to ensure I kept the Triban 3 going. When I looked at the rear rim, I realised that even if the damage caused by the spoke wasn't as bad, the rim was virtually worn through.
Getting a replacement rim is easily done, for 32-hole or 36-hole rims. For a 20-hole rim it's much more of a problem.

This wasn't a crisis, as I still had the rear wheel from my hybrid to fall back on. And yet, as I've always wanted to build a wheel from scratch, I started eyeing up the 32-hole rim that was part of the original stock wheel that had failed.

Looking for advice, I took to Twitter, asking what would happen if I laced a 20-spoke hub to a 32-hole rim. One reply was simply a single word: Hilarity

And that pretty much made up my mind: I simply HAD to build what I've come to call the Frankenwheel!

Now to build a wheel, there are a few things you need to keep in mind. For starters (though it seems obvious) you need to ensure the hub is EXACTLY in the centre of the wheel, else you'll have a very wonky wheel that would be better suited to a clown's use in the circus. Additional to that, as it's a rear wheel, it must be dished - that is the spokes on the drive side must be closer to the centre of the hub than what is the case on the other side. This is to allow space for the cassette. Also, the wheel must be true and free of kinks or wobbles. Finally, the wheel must be well balanced. This last one was the only bit that worried me, as there was simply no way to absolutely evenly distribute the spokes.

It REALLY helps to have a wheel truing stand when building a wheel, and I didn't have one. Some searching on Instructables.com, some scouring the shed for material to use, and some time later I was the proud owner of a crudely-made wooden wheel-truing stand, and the build began.

As I had a packet of new drive-side spokes, I replaced a few spokes with new ones and it really wasn't long before the wheel was taking shape. I was heavily focused on building it with the hub right at the centre that I lost track of the dishing. I ended up with a perfectly centred, totally true wheel that wouldn't fit the bike as I hadn't dished it. At all! D'oh!

Back into the stand it went and I got on with adjusting the spoke nipples. Now on a normal spoke, that really is simply a matter of turning the spoke key, but with Mavic bladed spokes you need pliers, or something similar, to hold the spoke and stop it from rotating. Still, before long I had a wheel that was centred, true AND dished. Was it balanced? Well, surprisingly so, though not completely.

I then fit the wheel onto the bike and yes, I started commuting on it. Additionally, I also went on a few club runs on Saturday mornings, and in no time at all I locked up around 700 miles on the Frankenwheel, without any issues whatsoever (except a puncture, which in this respect doesn't count).

I've since received my new bike, and I've been riding that exclusively, so I haven't put more miles on the Frankenwheel. I am planning on re-building it again, using a 20-hole rim, and it was never intended to be a long-term solution. Instead, it was something I did because I could, because it was a challenge and because sometimes I really do like to go against the advice I've been given.