Posted in Cycle

If you've decided to buy a mountain bike but you're not sure which is the best one for you, our comprehensive guide will have you hitting the trails in no time. 

Mountain bikes are robust, versatile machines but with so many types of mountain bike to choose from, it can be hard to decide. What features should you look for and how can you find the best mountain bike for your money? 

Whether you have your sights set on enduro racing or you just want a commuting bike that you can take on the trails at the weekend, there's a style to suit you.  

Should I buy a hard-tail or full-suspension mountain bike?

The two main types of mountain bikes are 'hardtail' and 'full suspension.' The most notable difference between the two is that a hardtail only has suspension in the front forks while a full-suss has front and rear suspension.   

You'll need to think about the type of terrain you'll be riding on and your budget before you decide which one you go for.  

What is a hardtail mountain bike good for? 

Hardtail mountain bikes are great all-round bikes. No rear suspension means the build is less complex and less expensive, so you can get a decent model for less money than a full-suss. This makes them a perfect choice for getting to grips with off-road riding and learning basic skills before you decide whether you need full suspension.  

No rear shock also means they are often lighter than a full suspension bike at a similar price point. This makes them a great all-round option that you can use for commuting and touring as well as weekend trail riding. 

What is a full-suspension mountain bike good for? 

Full suspension mountain bikes are perfect if most of your riding will be off-road. Although the rear shock can carry a weight penalty, it can provide extra comfort on long days, particularly for those who suffer from knee or back pain.  

The added bounce means you’ll get less traction on technical climbs so you might find that you’re slower. However, with the extra confidence you’ll get from having the rear shock, you might find that you’re faster on bumpy terrain and trail features like rocks and drop-offs. 

Should I buy a carbon or aluminium frame mountain bike?

The decision between a carbon or an aluminium frame will partly be decided by how much you can spend. Carbon bikes are generally far more expensive. 

Before you commit your cash, it's worth thinking about which material is better suited to the riding you'll be doing as the differences between the two materials mean they're both good at different things.

  • Weight - Although carbon is generally lighter than aluminium, the difference isn’t always as crucial as it might be on a road bike. Carbon frames are great for cross-country or enduro rides where you want to minimise weight on climbs. However, a bit of extra heft can be an asset for downhill riding.  
  • Torsional stiffness – This is the amount of flex allowed as you stomp the pedals – the greater the torsional stiffness, the greater the power transfer. Carbon frames generally feel a lot stiffer than aluminium ones and therefore a lot snappier. Great if you’re interested in speed over relatively smooth surfaces. However, for more rough terrain and aggressive riding, the flex in an aluminium frame can make for a more forgiving ride.
  • Comfort – The structure of a carbon frame absorbs some of the harshnesses on rough trails. This dampening effect, combined with the lighter weight, mean that many riders claim to feel faster and more comfortable on carbon, particularly over long distances. However, it’s worth noting that if a carbon frame is beyond your budget, you can still benefit if you switch out the handlebars and seat post for carbon.  
  • Strength – On modern mountain bikes, there isn’t a lot of difference between carbon and aluminium but it’s worth mentioning here because carbon has had a bit of a bad reputation in the past. Improvements in manufacturing methods mean that a good quality carbon frame can outlast an aluminium one provided it is looked after. Of course, nothing’s invincible and under extreme stress, both can potentially break, albeit in different ways.  

Are disc brakes better on mountain bikes? 

Disc brakes are a lot more reliable, particularly in bad weather where rim brakes would struggle to grasp the wheel. They also cope a lot better with dirt and grime where rim brakes would get clogged up.  

However, if you’re a beginner, don’t rule out rim brakes just yet. Rim brakes are lighter and easier to maintain than disc brakes. They also tend to cost less.  

If you’re buying your first mountain bike and you aren’t ready to pay the extra for discs, it’s a good idea to check if the frame is compatible with discs so you can upgrade later if you wish to.  

How much travel do I need on a mountain bike? 

Travel is the maximum distance that your front suspension fork can compress. More travel means more shock absorption, but it also means you’ll need to use a lot more energy if you want to go fast on the flat. Therefore, bikes with long travel are more suited to rough downhill trails whereas you’ll probably want less travel for cross-country or mixed-terrain riding.  

Short travel suspension 

Anything less than 120mm is also referred to as ‘short travel.’ If you’re riding on smooth trails, fire roads or tarmac and you want to be able to climb efficiently, a bike with short travel will give you all the shock absorption you need. However, on fast descents and trail features, less travel can make the steering feel twitchy which might knock your confidence. 

Long travel suspension 

‘Long-travel’ covers anything from 120 right up to 200mm of travel. Go for a bike with long travel if you want to take high-speed descents on rough terrain with confidence. Not only do you benefit from more cushioning, but you’ll also feel more in control. The longer the travel, the more suitable the bike is for descending. 

Adjustable travel 

Some front forks can be adjusted on the fly for greater versatility. This means you can ‘lock out’ the suspension if you’re facing a long climb or riding on tarmac between trails, then switch it back on when you get back to the rough stuff.

What is better - coil or air shocks? 

The shock is the component in the rear suspension system that absorbs the impact as you ride over bumps and off trail features. If you decide that a full-suspension mountain bike is the right bike for you, you’ll need to choose between two types of rear shock – coil or air. Just like the front suspension fork, the rear shock will allow an amount of travel and you should check that this is suitable for the type of riding you'll be doing before you buy.

Air shocks are popular because they are lighter than coil shocks and easy to set up and adjust. If your weight changes significantly, you can fine-tune the amount of ‘sag’ required with a shock pump. However, because they are essentially a pressurized air system, air shocks can be vulnerable to weather conditions such as heat, humidity and altitude so it’s advisable to check and readjust frequently.  

Coil shocks are common on downhill mountain bikes because they feel more consistent and grounded for riders tackling long, technical descents. Fans of coil shocks claim they feel more plush and supple. They are also simple to maintain – you can fit and forget. However, there is a weight penalty and they are less adjustable than air shocks. A significant change in your weight will mean you'll need to fit a new spring. 

Nukeproof dissent, coil shock, mountain bike

What are the best gears on a mountain bike?

The range of gears available to you will have a great impact on your enjoyment of riding so it's important to get it right. For example, might want to consider a higher range if you think you'll be doing a lot of climbing so you don't end up tired and frustrated. 

Entry-level bikes are often supplied with a triple cassette, meaning three cogs on the chainset (front cassette) so that you have the widest possible range of gears to help you to ride more efficiently as you build your fitness.

The most common chainset for hardtail mountain bikers is a double, which means there are two cogs at the front. This is often paired with a ten-speed cassette at the rear, which has ten cogs, although eleven-speed is becoming more common. A double should give most riders enough range to be able to tackle even the trickiest climbs.

It's becoming increasingly common on newer mountain bike frames to see a one-by, which means only a single ring up-front. Having a one-by removes the need for a front-derailleur - one less this to maintain, one less thing to get clogged with mud and less risk of dropping your chain when you shift. This is particularly attractive for aggressive downhill riding when you won't be doing much climbing. You'll often see this paired with a twelve-speed cassette. 

What wheel size is best for you?

There was a time when all mountain bikes were built with 26" wheels. Nowadays, there are three sizes to choose from, each one more suited to a different riding style.  

  • 26" – Lighter and more agile, 26" wheels are popular on dirt jump bikes but increasingly rare otherwise. They're smaller so some argue this is stronger and therefore more suited to thrashing downhill. The compact size also means they're fine for narrow, technical trails. However, smaller wheels don’t roll over obstacles as easily as larger ones which means that overall handling can feel more twitchy. 
  • 27.5" - also known as 650b, 27.5" wheels have the same snappy acceleration as 26", but they're much better at rolling over obstacles so handling feels a lot more confidence-inspiring. They've rapidly gained popularity as a perfect compromise between 26" and 29", giving you the best of both worlds.
  • 29" – The larger diameter means you can effortlessly roll over obstacles like a tank and hold speed over distance. Bigger tyres mean increased grip and stability which is confidence-inspiring for beginners. However, bigger means heavier, and a larger diameter means it will take longer to get up to speed and you'll feel less nimble on narrow trails. 

About the author

NChamanian's picture
Nassrin Chamanian
Published on: 22 Jul 2020

Pretty OK at bikes. Enthusiasm outstrips ability.