Why Carbon? – The majority of people will look towards carbon wheels to save weight. Indeed carbon mountain bike rims are lighter than their alloy equivalents but there are many more advantages to running carbon wheels than just a little saved weight.
The lighter weight material allows for wide rims that are still lighter than much narrower alloy equivalents. This flattens the tread of the tyre to give more grip and the same tyre contains more air at any given pressure which means you can confidently run at lower pressures giving you even more grip and a smoother ride.
Speed and Handling advantages from increase in stiffness:
Carbon rims are much stiffer in both vertical and lateral directions. If you push down on an alloy rim, even a heavy downhill version, you will be able to flex it out of a circle and into a slight oblong. Try this with our carbon rims and you cannot budge them however hard you push which shows the difference in vertical stiffness between the two materials. When you ride on carbon rims and your bike feels faster, you are feeling the benefits of your wheels staying completely circular as they impact on rocks and stumps or increased pressure is applied through the rim through jumps and landings.
There is the same difference between carbon and alloy rims in lateral stiffness and this is why there is such a marked difference in tracking and steering feel between the two materials. An alloy rim will twist under cornering / steering loads and when rocks and obstacles introduce sideways forces into the wheel. With a carbon rim being so much more laterally stiff, both wheels will track a line through rocky terrain and front wheel grip is much more consistent without the constant flex and spring back during cornering of an alloy rim. This also gives you much more feel for what your wheels are doing and allows you to push much closer to the edge of available grip through turns.
You still hear rumours that carbon rims give a harsh ride due to increased vertical stiffness. However, carbon is naturally much more vibration absorbing than alloy and allows manufacturers to tailor the behaviour of the rims by varying materials and lay-up techniques. Anyone who’s played tennis with both alloy and carbon framed rackets will know what a big difference there is in the levels of vibration reaching the handle between the two materials. Similarly noticeable is the difference in ‘buzz’ between alloy and carbon framed road bikes. In mountain biking all impacts start at the tyres, and then take a route through rims, spokes, hubs, forks / frame…. eventually reaching the rider through the bars and pedals. With a carbon rim, much more of this impact / vibration energy is absorbed by the rim before it can be passed up the spokes towards the rider. This is extremely noticeable with a smoother ride and your same bike will become instantly much quieter – lots of our customers have commented on this.
The biggest negative to using a carbon construction for mountain bike rims is the expense of the materials and the manufacturing process. While not many people would describe wheels costing over £700 as cheap, we believe our wheels are the best value carbon wheels available and at a similar price to top end alloy wheels which are leagues below in terms of performance.