Knowledge Level: Intermediate
Carbon fibre is an incredible material that has revolutionised bike frame design and performance. It is lightweight, corrosion-resistant, can be formed into almost any shape desired and is very strong for its intended uses. Scare stories about carbon frames and components being universally fragile and unreliable simply aren’t true. It’s strong enough for Formula One and aerospace applications, so is certainly strong enough for your bike.
If produced by a respected and established manufacturer and correctly looked after, there’s no reason why a carbon frame shouldn’t give you many miles of happy riding and many manufacturers now offer lifetime frame warranties. Quality is key no matter what frame material you choose and, whether carbon, steel, alloy or titanium, high quality will always prove more durable. There’s no need to change the way you ride with carbon but there are a number of simple steps you should take with its care and maintenance.
Buy a torque wrench
Although incredibly resistant to forces in the direction it is designed for, crushing can easily damage carbon fibre. Over-tightening of clamps and bolts, such as handlebars and seatposts, is one of the most common causes of carbon fibre damage and failure. All components on a carbon fibre bike will have recommended torque values given in newton metres (Nm) that will either be marked on the relevant component, available in the supplied manual or on the manufacturer’s website. A torque wrench ensures that you don’t tighten beyond these values and should be considered essential if you own a carbon fibre bike. If you have only previously owned metal framed bikes, you’ll probably be surprised how little force is required.
Use assembly paste
One of the downsides of the relatively low torque values required by carbon frames and components is that they can be prone to slipping. This especially tends to affect seatposts. Don’t be tempted just to tighten it up an extra half turn but use some carbon assembly paste. This is a gel that contains particles that, when applied as a thin layer, increases mating friction between the surfaces and stops slipping. Along with a torque wrench, assembly paste is a carbon must-have.
Handle with care
Crashes are often unavoidable but many impact incidents that can damage carbon are easily avoided. One of the most common is letting the handlebars spin round and smash into the top-tube. Take care when picking up your bike to not let this happen. Try to avoid stacking your bike against others or leaning it with the saddle against poles or pillars. It’s too easy for the bike to slip and crash into it. Level surfaces such as walls are far safer. You don’t need to be neurotically paranoid and wrap your bike in cotton wool, just take sensible precautions to avoid unnecessary impacts.
Keep it clean
Regular cleaning gives you a chance to inspect your bike, check for visible signs of damage and, regardless of frame material, should be part of your riding routine. Avoid any harsh solvents that may compromise the epoxy resin that binds the carbon fibre and, if in doubt, consult the manufacturer’s recommendations. Any degreasing or cleaning product designed specifically for bikes should be suitable as well as good old fashioned soapy warm water. You may also want to give your frame some extra protection and shine by finishing off with some bike polish.
Avoid the crush
As we’ve already mentioned with regards to not over tightening components, carbon fibre is prone to crush damage. Care needs to be taken when using work stands and car racks that clamp onto tubing. Use the minimum pressure required to hold the bike in place, clamp onto foam pipe lagging for extra protection and maybe consider an alternative system for transporting your bike. If you’re intending to fly with your bike, we would strongly recommend a hard case.
With metal framed bikes and components, it’s quite normal and acceptable when installing components such as bars and seatposts to put them into position, tighten and then give them a twist or a tug to check they’re snug. This process can easily damage carbon fibre and should be avoided. Torque to recommended values, use assembly paste and, if the component needs adjustment, completely loosen it off beforehand.
Measure twice, cut once
If you’re needing to cut a carbon component, such as handle bars or an integrated seat-post to size, always measure carefully, wrap with tape to show exactly where you need to cut and then use a carbon specific hacksaw blade which will avoid tearing and fraying the fibres. Never mark a carbon seatpost to show your position as even the smallest scratch can compromise it. Use a wrap of insulating tape instead.
Avoid chain suck
Chain suck occurs when the chain does not release from the bottom of the chainring. It’s most common on mountain bikes when using the smallest “granny” chainring. The chain sticks to the ring and gets sucked up and wedged between the chainstay and chainring. It's a real pain and, especially on carbon framed bikes, can easily cause significant damage to the frame. If chain suck happens, stop pedalling immediately and avoid the gears that are causing it for the rest of the ride. Once home, thoroughly clean and re-lube your entire drivetrain. Check for stiff links, chain stretch or worn chainrings and, if necessary, replace those components.
Change your pads
If you alternate between alloy training wheels and carbon race wheels, it’s essential you change your brake pads. Although there are dual compound pads available, alloy braking surfaces can leave metal shards embedded in the pads which can easily destroy a carbon rim.
If the worst should happen
Crashes and accidents do happen but, unlike a metal frame which can show damage in the form of dents or bends, carbon fibre can appear undamaged but still be dangerously compromised. If you have a crash and are worried about your frame, err on the side of caution and have it professionally inspected. Even severe damage to carbon fibre frames can be repaired and, although these repairs may not be aesthetically perfect, if performed by a qualified professional the frame will be safe and functional to ride.