I rode out with CTC Cambridge today (Sunday, 31 January 2016) and Alex happened to mention he'd been on a wheel-building course the day before, at which he'd learned that building wheels is really hard. As it happened, I built myself a new back wheel just yesterday, too, and was riding it today — I've built wheels that have stood the test of lots of kilometres. I don't profess to be an expert, just to having built a few wheels that have rolled true enough and haven't collapsed on me. I thought I'd write up my wheel-building experiences to offer encouragement to others wanting to give it a go — our 16-year-old son is building a new rear wheel literally as I'm typing this
I think of wheel building as a methodical process of suspending a hub in the dead centre of a rim with enough tension in the spokes to carry my weight over lumps and bumps. As I'm an engineer, I see the loads and forces involved and how tweaking the length of one spoke may affect the three-dimensional shape of the wheel. This can all be easily learned through trial and error and it's nothing to be wary of. Having said that, when I've finished building a wheel, I usually ask Dave at my LBS to take a look and give me his honest opinion! Experience is the one thing you can only get by doing it, so I rely on Dave's to give my wheels the thumbs-up.
Wheel building does require a small investment in tools, and each wheel takes three to four hours to build (versus paying your LBS £25 or so to do it for you), so unless you're building a lot of wheels, you don't do it for economy reasons. There's a certain satisfaction gained from building your own — in a Zen-like way — especially as the experience demystifies fixing your own and re-truing a wheel in the frame if you have an incident on a bike ride!
When I got my Ribble old-style steel bike a few years ago, it came with Shimano R501 deep-section wheels, which proved somewhat uncomfortable on long rides. I quickly decided I wanted to have a dynamo hub on the front wheel to power a decent German bike light, and therefore I also wanted to build a matching rear wheel, just for the look of the thing
That was several years ago and at the time I bought a cheap truing stand and dish tool from Rose Bikes and built up a couple of wheels:
- Shutter Precision SP-PV8 3W dynamo hub on the front (black) — an unknown, but reliable enough by reputation, half the price of SON (lighter, too) and just as efficient
- Shimano 105 hub on the rear (black) — reliable and repairable in any bike shop
- Mavic Open Pro rims (black) — good, strong rims for audax reliability
- DT Swiss Competition double-butted spokes (black) and nipples (silver) — good, strong and pretty spokes and nipples
- Continental rim tape (blue!) — it's that or PVC tape
I built the wheels to Roger Musson's method — Roger used to build wheels for pros and has a lifetime's experience, and yet his manual on wheel building is written with humility and is full of practical observations for the newbie wheel builder. It's only available as a PDF to download and for the money it's really well worth it!
By the end I had a pair of almost-true wheels, but built in a way that should make them strong — it's better to have strong wheels than true wheels if you can only have one or the other. Roll on at least two years and 5000+ kilometres and both wheels are as true as they were back then
I now have a new bike — a much simpler and cheaper fixed-wheel bike, which I also ride for audax. Since it's currently January (2016) then the days are short and the nights are long, so I moved the dynamo wheel from my red bike to my fixie, but that meant having non-matching wheels. No problem: I'll build a new rear wheel to match the front.
Getting the rim was the first problem: Mavic have changed the sticker since then and so to have matching wheels I had to source a new old-stock wheel with the old sticker, which Bicycle Ambulance in Cambridge helped me with I also bought a Brick Lane Bikes (rebadged System X) double-fixed hub from them.
Next the spokes: buying spokes in the UK is a very expensive business, typically 60-80p per spoke, so 32 spokes would be £20-27 including nipples. It's much cheaper to order spokes from Rose Bikes in Germany, since they are around half the price (although bear in mind that delivery from Germany is £7.60).
As it happened, at about the time I'd ordered everything, but was waiting for the delivery to arrive, I discovered one of the bearing cones on my factory-fit rear wheel had come away from the locknut and tightened down on the bearings, causing some significant scarring to both the cup and the cone. Dave at my LBS re-greased and reassembled the bearings, but suggested its life was limited — definitely time to build that new rear wheel!
The package arrived from Germany, I cleared the dining-room table, and set to work.
Musson is meticulous. When you order spokes they must be the correct length. He makes you measure each rim independently — never trust manufacturer's data for effective rim diameter or ERD. Hubs are easier as they are machined more precisely. He provides an online spoke calculator to get just the right length of spoke every time — it has worked for me every time. When you lace the wheel, he suggests aligning the logo on the hub and the valve, as a sign to others that you pay attention to detail — and he shows you how.
For this wheel build I would be lacing a double-fixed hub into the rim using a three-cross pattern — this is exactly like a front-wheel build in that the wheel is built dishless with the same length spokes on both sides. Compare this to a standard rear-wheel build where the drive-side spokes — the ones next to the sprockets — are shorter than the ones on the other side.
Building wheels is very Zen-like — it's best to do it in a quiet room without any disturbances or distractions. If you have the telly on, for example, it's almost guaranteed that you'll lose your place on the wheel and create more work for yourself later on. It's much better if you focus on the wheel and nothing else.
The process for building wheels is straightforward once you've ordered all the parts.
Lightly oil every spoke hole in the rim (not the hub) and make sure every spoke has some oil on the threads — like a vignette from a Japanese restaurant, I used the cap of a soy-sauce bottle to hold the oil to dip the spokes into, and a piece of bent card as a chopstick holder. I use chain oil, because I have a bottle to hand, but any 3-in-1 type viscous oil is fine.
Work out the first spoke position for the specific rim — it's a very important step — and lightly spin a nipple onto it. The hub and rim are now attached by a single spoke.
Insert the other seven spokes on that side of the hub and spin nipples lightly onto them.
Now do the same on the other side — 16 spokes are lightly attached.
Now do the same for the eight spokes that come through from the inside of the hub flange on one side — this is the first time any proper lacing has been done as the spokes all cross over, either 1, 2, 3, or 4-cross.
Do the eight remaining spokes.
Check the lacing looks about right — the wheel at this point will look an utter mess with the spokes looking like the bits of bent wire they are.
Check the logo is actually opposite the valve — it took me four goes to get this right yesterday!
Now take your nipple driver — I use an adjustable nipple driver with a short, magnetic extension rod for this part and spin it between my finger and thumb until the driver no longer turns the nipple. The pin should be sticking out about 1.5mm or so.
Once you've pre-tensioned all the spokes all the way around the rim, give or take, every spoke is in the same position as all the others, the rim will be central on the hub and dished correctly. Give or take a smidge in every direction. This should all be done by hand so you can feel that every nipple is running smoothly on every spoke. You can put the nipple driver down now and reach for the Spokey.
And now the fun really starts!
It's now necessary to mount the wheel in the truing stand. A piece of tape around the rim at the valve hole is a useful marker: start with the spoke on one side or the other of the hole and work consistently around the rim until you get back to the valve hole.
You need to give every spoke exactly the same number of turns to bring the wheel into tension: how much depends exactly on how far the pin was sticking out when you pre-tensioned the wheel. I started with a full turn each, then a half turn each, then a quarter turn each until the wheel had a reasonable amount of tension — at this point it looks like a rideable wheel, but you can't ride it just yet!
- Check the dish: take the wheel of the stand and use the dishing tool to confirm it's still in the centre between the locking nuts — dish is measured to the outer face of the locking nuts and not to the ends of the axle and it's important you get this right! If the wheel is dished to one side or the other then you need to tighten the spokes by a quarter turn or so on just one side to neutralise the dish. However, if at this stage the wheel isn't true then it's important you give it some basic trueness before dishing!
- True the wheel: try to get rid of any high or low points by pulling the rim one way or the other by tightening spokes a little at a time.
- Also centre the wheel: it must run perfectly around the axle, otherwise it will bounce you down the road.
- True it again, dish it again, centre it again. The process basically follows to bring the wheel up to tension and into true and dished correctly all at the same time.
You also need to destress the wheel: with a thick pair of leather safety gloves on, squeeze opposite spokes together really hard to release any stored twist or stiction — you do want to release it now, because if it releases while you're riding then the wheel will quickly go out of true, in about 10 minutes of riding!
You do this over and over until you are satisfied with its strength and that it is true enough — a wheel doesn't have to be perfectly true, but it does have to be strong. Musson makes the point that in the later stages turning the nipple just twists the spoke without changing its length, and if allowed to remain twisted, the spoke will unwind when ridden and the wheel will lose its trueness — use bits of sticky tape, just like he says, and don't skimp on this bit, because it really pays to get it right.
As a final test, put the wheel on a hard surface like a paving slab, resting on the end of the axle and apply most of your body weight to opposite sides of the rim, like you're doing a press-up — laterally loading the rim in this way is a good indicator whether there's enough tension in the spokes. If the rim easily deflects then you'll have to add tension to every spoke by the same amount — by this point it should be a quarter-turn or an eight-turn to every nipple. And then check and true all over again!
You will probably need to iterate through this process until you're satisfied you've built a strong-enough, true-enough wheel, which can take several hours. Once you've finished, though, you can point at the wheel and say "I built that" and if, like me, your wheels stand the test of time then you can be rightly proud of your efforts!
Addendum One more thing: you must put enough tension into the spokes so that they don't come unwound over bumps, but not enough to tear the thread out of the nipples. Without a spoke tensionmeter then you'll have to do this either by trial and error or by comparing with an existing proven wheel.
Finally, you can put the rim tape on — make sure the valve hole aligns with the hole in the rim! — and add a tyre and inner tube and fit it to the bike. Of course, if it's a rear wheel then you also have to fit the gears. For me, this meant removing the fixed-wheel sprockets from my old rear wheel and tightening them onto my new wheel — this requires a lockring tool and a quarter-inch chain whip, but only takes a couple of minutes.
I rode the wheel today
My nuts are too big
One problem I came across with this build was that the axle on the new hub was too short for my frame, because the track fork ends (dropouts) on the rear are 10mm thick each side. The axle on my old hub is 170mm and on the new hub it's 160mm. Too few threads of the nut are engaged on the axle for it to be safe.
On inspecting the standard track nut, it's clear that the first 5mm of the nut are devoted to the captive washer — if I could get rid of that then I would probably be okay. Bicycle Ambulance were able to help, providing non-washered nuts and suggesting a slim washer underneath — this was just enough to get the nuts tightened down safely
I used a centre punch to create a pock-marked surface on one face of each of the washers to help them grip the fork-end plates when me standing on the pedal tries to force the wheel to slide forwards.
Do I need to use a spoke tensiometer?
No. Um, maybe …
I've asked around in various bike shops and the like and nowhere uses one of these when building wheels. People on the Internets make a loud noise about having to use one, but it's not true — and they are very expensive, so a luxury.
They might help, but having never used one and with wheels that have remained true, I won't be buying one any time soon.
Addendum — hard-won experience on spoke tension!
For inexperienced builders, I've come to the conclusion that a tensionmeter might help build stronger wheels by giving the novice builder the confidence/knowledge that at least enough tension is present in the spokes to prevent them unwinding.
What happened to me is that I went out for a hilly 240km bike ride yesterday (7 February 2016) and I could feel a bit of untruth in my rear wheel at about 200km — I happened to be flipping the wheel and checked and could see the wobble in the wheel; however, it was only about 2mm, so I thought I'd ride it home and true it there. It felt noticeably worse as I got closer to home. I've just re-checked in the light of day and the wheel will need to be completely re-tensioned — I'm surprised it got me home, because many of the spokes are completely slack, zero tension at all. I think the only reason I did get home is that Open Pros are Mavic's strongest rim (at the cost of being a bit heavier) and I'm not particularly heavy at under 12st.
The mechanics of the problem is this: when you strike a bump then the rim deforms slightly at the bottom, as well as the spokes around the upper half stretching slightly. This has the effect of temporarily reducing the tension on the spokes in the lower half at that moment, particularly the ones nearest the ground. If there isn't enough tension in the wheel then momentarily these lower spokes become all-but un-tensioned, which allows the spoke nipple to turn due to vibration. Do this enough times and the spoke will become unthreaded and the wheel will fall out of true, as happened to me This is a self-accelerating problem, since each micro turn of any spoke nipple reduces the tension in the wheel overall, which increases how often that spoke and the rest in the wheel become momentarily untensioned, gradually allowing all the nipples to unthread, and the wheel de-tensioning will accelerate to destruction!
The good news from this is that I've learnt something I didn't previously realise: to make sure there's enough tension in the spokes. Probably I needed another half-turn to full-turn all the way around — that doesn't sound like much, but it is (I think). Next time I won't be quite so conservative when applying the final tension. What I didn't do with this wheel was show it to Dave for his experienced comments — he would probably have spotted the lack of tension and saved me an embarrassing mistake.
FWIW, I do carry a spoke key, so if I had realised just how loose the spokes had become then I would've stopped and put a load more tension back in, using the frame and brake blocks as my truing stand — at a pinch a wheel doesn't have to be perfectly true, just 'good enough'. It would taken only about 10-15 minutes to do this and I had nearly two hours in hand at the end anyway.
When you've built your wheel — and I mean when I've built my wheel — then ride it and if you find slight untrueness has crept in after 100km or so then it's possible you need to apply more tension all round.
I rode the bike today on an 80km CTC Sunday ride and I've just been out into the cold to check it — it's still true! But note what happened after my 240km ride, above — not quite so smug any more, and certainly wiser and more experienced!
Building wheels takes some concentrated effort and a small amount of investment in tools, but it's a straightforward process and if you just follow Musson's teachings step-by-step and strictly follow all of his anti-twist advice then you should end up with strong, round wheels that will carry you a long way and you can be rightly proud of. Just remember to put enough tension into the spokes for them to never become unloaded and vibrate the nipples loose.
Now, I just need to pop to the room next door to check on how Ben's getting on with his wheel …