Trueing a Wheel

Before I start I’ll apologise for the condescending tedium that will surely follow in some parts of the notes below – I know how easy it is to make a complete pigs ear of this. Not really a super-faff in the true spirit, more a bit o’ maintenance, or maybe bitter maintenance is a better term? Enough waffle, let’s get on with it.

The Problem

Pretty obvious, your wheel is buckled. It catches on the brake pads/blocks as it spins, maybe wobbles as you whizz round corners, or worse. This weekend a few of us hit a nasty pot-hole and gained wobbly wheels in the process. Bugger.

Tools

You’ll need a spoke key and a piece of chalk. Spoke keys cost about a fiver and if you haven’t got any chalk a crayon will do or failing that a marker or ball point pen is a poor alternative

How the Wheel is put together

At the most basic level the wheel has a hub at the centre, a rim around the outside and a set of spokes tying the two together. Stood in front of the bike and looking at the front wheel you’ll see that going around the rim spokes are laced alternately to the left and right of the hub. Broadly speaking the spokes on the left have the same tension as those on the right and together they hold the rim straight, ‘true’. Without the spokes holding it, the rim would be all over the place – it would not be true, no way.

Each spoke threads through a hole in the hub and screws into a nipple at the rim, or rather the nipple screws onto the spoke. The nipple is fed in from the outside of the rim and is usually hidden beneath rim-tape.

Finding the buckle

Before we can straighten the wheel we need to find the buckle. Professionals will place the wheel on a not-so-fancy jig so that the wheel can spin freely. I turn my bike upside down and leave the wheel securely clamped in the front/rear forks.

First job is to check that your wheel doesn’t wobble from side to side on the spindle – lateral movement points to loose cones and it’ll be virtually impossible to do a good job of trueing until the cones are sorted out. If you can wobble the wheel from side to side, you need to deal with that first.

Assuming there isn’t any lateral movement, spinning the wheel as fast as you can might show the buckle really well but it doesn’t help does it? You need to roll the wheel round slowly. Find the point where the buckle starts. Check again and again by rocking the wheel back and forth – I usually use the brakes blocks as a good visual guide to spot the wobble. When you are sure you can see exactly where the buckle starts mark that point on the tyre/wheel with the chalk/crayon. Then do the same for the point where the buckle finishes. Step back and admire your skill thus far – you can now clearly see the section of wheel than needs attention. 

If your wheel is really messed up it may be buckled in more than one place and wobble all over the place. You’ll need to mark each buckle and maybe ad an arrow to indicate which way you need the wheel to go to straighten the buckle.

Straightening the wheel

Luckily it’s all about tweaking the nipples, so says the man who has spent too much time alone in the garage. With your marked-up wheel you know exactly which section you need to adjust and which way it needs to go. First you loosen the spokes on the side of the wheel you wish to move away, then you tighten the spokes on the side you want to pull it towards. That’s all there is to it, except for a little finesse:

-          the buckle always starts small, gets bigger, then is small again. The further away from true a particular point of the rim is the more the spoke at that point needs to be adjusted

-          do a little bit, review your work, then do a little bit more if necessary. Do not be tempted to do too much in one go, you’ll  only make it worse.

-          I start with about a sixth (1/6) of a turn on the spokes at the ‘small’ end of the buckle and about a third (1/3) of a turn on the middle ‘bigger’ part of the buckle.

-          Always loosen the side you want to release first, then tighten the side you want to pull back into position.

-          Don’t rush, working slowly, bit by bit really is the way to go. Tortoise, not hare.

-          Repeat as necessary.

-          When you think you’ve done, ride on it and re-check.

Fancy front wheels with very few spokes are likely to be harder to tackle than rear wheels with loads of spokes.

Clockwise to tighten

MOST IMPORTANT. The spoke and nipple have normal threads, clockwise to tighten, anti-clockwise to slacken. BUT for the nipple this is from the outside. When you put your spoke key on the nipple make sure you turn it the right way – clockwise from the outside is anti-clockwise when viewed from the inside. Think about it!

So how did it get buckled?

Apart from hitting the pot-hole / stunting in the skate park?

All the spokes are under tension, and the tension keeps the nipple tight on the spoke. When the wheel gets a shock load the tension is released from one side and the nipples can unscrew a little. Doesn’t take much because there’s so much force in them – how else would they stay round while taking a pounding from your 15-stone muscle-bound self?

Knackered Rim Jim?

A properly buggered ring may be unrecoverable. One that is merely damaged may be recoverable. Before faffing trying to straighten it, assess the damage, assess your appetite for fixing it, assess your wallet and take a cheeky look at Evans/Halfords/ebay etc.

First problem is if the rim is f*ked where it meets the tyre. Serious pot holes can gouge or crack the rim – knackered. If the rim is just ‘folded’ a bit then a careful tweak with pliers can put it back where it should be (or a little tap with a hammer for steel rims). If the tyre wont sit on and be held properly by the rim then it’s game over, simply not safe – bin the wheel and get out the credit card. If the outside is ok, next look at the section of the rim where the brake blocks clamp it – this should be smooth and even to the naked eye. Lumps or dents are bad – lumps will cause the wheel to lock under heavy braking and need to be gone, dents aren’t so terminal. Delicate work with a 12oz hammer might sort out any lumps, or failing that any hammer short of a sledge hammer. In this state though you have little to loose, so either try it or bin it.

Providing the rim holds the tyre properly (thorough visual check) and the brake-face is flat you’re still in with a chance of recovering the wheel.

Final Words

For me, DIY (destroy it yourself) maintenance used to be about saving pennies, these days its as much about saving time as money. Professionals will typically do a better job and quicker, quicker that is if you don't count the time it takes to drop bike/bits off at the shop and collect them later. Bitter experience tells me that sometimes it is better to swallow pride and pay a man to do a job rather than quite literally destroy it myself and end up with a bigger bill. You have to make your own decision on this. Though if you never try, you'll never learn.

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