When purchasing a high end mountain bike or building up your dream bike you'll come across two material options for rims, carbon or aluminium. Both have their pro's and both have their con's. But carbon rims aren't necessarily a tonne lighter than aluminium rims depending on the model, there is so much more to it! So, which rim is best for you? We discuss your two options.
Aluminium mountain bike rims have been around for a seriously long time now and there's good reason for it. The technology has evolved over the years to give us modern rims that are strong and well weighted. A common misconception is that carbon rims are more favourable due to being light weight but with advancements in aluminium rim design there are some light aluminium options out there that can even rival a few carbon rims on the scales!
Some hard, fast and rough racers may favour an aluminium rim as they will dint before they have a total failure, unlike carbon rims. When racing a dint in the rim that lets you complete the race is far more appealing than a complete failure that can end your day then and there. There is also the undeniable fact that they are a lot cheaper than their carbon competition. Although there is also the cost of labour for a wheel build and spokes (if required) to consider if you're particularly rough on your wheels.
Yeah, carbon looks cool but there's a whole lot more to it than that. When designed correctly carbon is damn strong. Yes it can break, everything can break. But to break a good, modern carbon rim will require a seriously large impact that you can safely say would break a comparable aluminium rim. Another advantage with carbon rims is that depending on what brand you chose their warranties look after riders really well. We Are One Composites offer a lifetime limited warranty on their rims while Enve Composites have a five year warrantty.
Weight was once considered the big attraction to carbon MTB rims but this has now shifted to ride quality. Carbon rims were renowned for being too stiff and very rough to ride with the wheel bouncing off bumps and skipping all over the place. As manufacturers have gained greater understanding of the material riders are rewarded with rims that are compliant in the rough yet stiff when needed cornering. This can give you the added confidence and control to go faster on the trail as the rim helps take some of the harshness out of the trail.
Based on our experiences, due to the advancements in carbon technology and manufacturing a well made / engineered carbon rim will be favourable with their great ride quality and extremely high strength to weight ratio. Although, the aluminium rim still has its place offering great performance at a more reasonable price that may suit some riders and racers more.