Workshop: Truing a pair of wheels
Truing A Pair Of Wheels (Bikeradar)
Following on from our guide to wheel lacing, here we show you how to complete your wheel build by tensioning, dishing and truing them. If you don’t have any experience of wheel truing, you need to take this very slowly.
Tools for the job - essential kit
1 - Spoke key
2 - Flate blade screwdriver
3 - Wheel jig (ideally)
4 - Dishing tool (ideally)
5 - Ruler or Vernier calliper instead of 3 and 4
Step-by-step guide
1] The first job is to wind all the nipples down an even amount on each spoke. Grab your screwdriver and, using the slot in the end of the nipple, wind them down the spoke until the end of the nipple just obscures the thread on the spoke. If you need a guide, put your thumbnail in the last thread on the spoke.
2] Next, you need to evenly tension the wheel. Do this by adding one full turn on each nipple. Start at the valve hole – it can act as a reference point so you know when you’ve done one full rotation of the wheel. Continue adding one turn at a time for each rotation until about 75 per cent of the required tension is achieved – use a spare wheel as a reference for the tension required.
3] The spokes now need to be bedded in. Place it with the axle on the floor and the rim touching the floor nearest you. Now, put your hands on the rim slightly back from the centre line of the wheel and push down till you hear a ‘pinging’ sound. Rotate the wheel one eighth of a turn at a time and repeat all the way round the wheel. Then flip it over and do the same for the other side.
4] Time for an intermediary true. Ideally, you should have a wheel jig to do this, but most people don’t have one knocking about in the cupboard, so you can true the wheel in the frame or fork of your bike. Simply put the wheel into the bike as normal, with the bike in a workstand or upside down, and you’re ready to go.
5] Spin the wheel and hold the spoke key against the frame or fork. Move it towards the rim until the spinning wheel starts to rub the spoke key. This shows that the rim is deflecting in the direction of the key.
6] Stop the wheel where this contact occurs and, with the spoke key still held against the rim, rotate the wheel back and forth to count the spokes over the length of the deflection. Add a quarter-turn to each spoke attached to the hub on the opposite side to the deflection (a). Back off a quarter-turn on each spoke attached to the hub on the side of the deflection (b). Continue this on both sides until the wheel runs true.
7] Now check that the rim is central over the hub (or ‘dished’ correctly). Ideally you should use a dishing tool, but again, you can just use the bike. With the wheel in the bike, measure the distance from the inside face of the frame or fork leg to the face of the rim on both sides. This will tell you if the rim is centred in the frame.
8] To centralise the rim, loosen by half a turn to each of the spokes attached to the hub on the side closest to the frame, and add a half-turn to each of the spokes attached to the hub on the other side for one revolution of the wheel. Start at the valve hole and use it as a reference point so you know when you've completed a full revolution of the wheel.
9] Once you have the rim centralised in the bike, the wheel will need a quick true up. Inevitably it will go out of true when you’re centralising it, so repeat steps 5 and 6.
10] The wheel now needs to be trued in the vertical plane, too. This is similar to steps 5 and 6, but truing out the up and down movement of the rim. Again, the ideal set-up is to use a wheel jig, but the bike can come to the rescue if you don’t have one. Just put the wheel into the bike as in step 4.
11] Spin the wheel and, with the spoke key held against the frame or fork, bring it down until the rim lightly rubs on it. Where the rim hops outwards, count the number of spokes the deflection is over and tighten them by a quarter-turn. Where the rim dips away, count and again, loosen by a quarter-turn. Always adjust even numbers of spokes to keep the wheel in true laterally.
12] Take the wheel out of the jig or bike and repeat bedding in the spokes, as in step 3. Then the wheel will need truing, so repeat steps 4, 5 and 6.
13] All that lateral and radial truing can put the wheel out of dish, so you'll need to re-check and adjust accordingly. Repeat steps 6 and 7. It’s also a good idea to give it another quick true, so repeat steps 4, 5 and 6.
14] The wheel is now ready for its final tension. Add half a turn on each spoke for a complete revolution of the wheel, starting at the valve hole as your reference point. Continue adding half-turns until the required tension is achieved. Knowing exact tension comes through experience – you can use another wheel for reference.
15] The final fine-tuning is now required, so you need to repeat steps s to 13 to get the wheels running perfectly true. Make sure you put a rim strip over the spoke holes, whack on your tyres and tubes and you've created your first set of wheels.
Workshop Wisdom
- Wheels do bed in during the first couple of rides, and this can lead to a slight loss of tension, or running slightly out of true. Therefore it’s always a good idea to check them after about 4 hours of riding, and to add tension where needed and get them running true if required.
- When you’re bedding in the wheels, put a small block of wood under the axle so it doesn’t damage your floor or the end of the axle.
- Patience is the key when it comes to wheel building. Never try to rush the job.
- Judging the spoke tension required only comes through experience. A tension gauge, like the Park TM1 can shortcut this. It costs £60, but will help you build correctly tensioned wheels from the off.
- Always use a good quality spoke key. Our favourites are Buddy’s Spokey and Park’s SW range. Be sure to get the right size for your spoke nipples though.
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