Hospital of Hard Knocks

Nine days on some of South Africa’s toughest trails will take its toll on any mountain bike. Even if you’re fortunate enough (as I was) to suffer not one mechanical failure in 900km, the post-race service is essential. I took my Scott Spark in to Cycle Lab in Fourways and sat in on the initial assessment with mechanic Sean Wightman to learn more about what happens when you hand over your machine.

The patient.
The patient.

Step one is a simple inspection. A careful scan should pick up issues like cracks in the frame, although that’s fairly rare and needs a major crash. So I passed this one.

Next, Sean removed the wheels and looked for signs of decay on major components. You want to see how much your cables have stretched and analyse the brake pads for both the extent and pattern of wear. My brakes may have been knocked a fraction out of alignment, and weren’t quite flush with the disc.

The chain, a mountain bike’s metaphorical heart, is something I’ve learned to give special attention. Hundreds of kilometres spent transferring all the force you can muster from your legs to the wheels will fatigue even the best models. Sean recommends checking you chain every 160km, even though it’s unlikely to need replacement at such short intervals. His nifty tool found mine substantially beyond the 0.5mm limit of stretch and in need of immediate replacement.

MTB is a game of millimetres.
MTB is a game of millimetres.

You can prolong your chain’s life with proper maintenance. Weekly cleaning with a de-greaser and lubing minimises wear from the grit that tends to build up. “The name of the game is reducing friction,” Sean repeats.

Your wheels will take a hammering from even fairly tame mountain biking. Another basic check is that they’ve retained their shape. Again we’re talking about distortions of a millimetre here and there.

Some ingeniously simple tools make the job simple.
Some ingeniously simple tools make the job a breeze.

Sean recommends checking your shocks every 25-35 riding hours. These are advanced bits of kit, but the sealed system is not totally immune to the elements. Dust can find a way in there, and then you may as well be on a donkey cart. A good tip is to turn your bike upside-down during your weekly maintenance session. Then, when you clean your shocks, rub away from the seal to avoid pressing any water or dirt into the system.

A weekly clean will save a lot of money.
A weekly clean will save a lot of money.

Another key is alignment of the chain. Your front and rear derailleurs need to be positioned so that the chain is as straight as possible. Just a few mils off and changing gears becomes a test of strength and patience. You’ll also reduce the live of your chain. Mine was marginally off target, but an experienced mechanic like Sean will fix that in a matter of minutes by adjusting two bolts on the derailleur itself.

A straight chain is a healthy chain.
A straight chain is a healthy chain.

That covers the basics. A major service will require opening the likes of the bottom bracket and fully servicing them. That’s a must for older bikes or when you’ve been through extreme conditions like salt water.

Of course, you can avoid much of the mechanical machinations if you ride a road bike. There you’re looking at a service every six months or so. If you’re a serious mountain biker, that comes down to about once a month. As any MTB addict will tell you, it’s totally worth it.

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