The Insiders Guide: How to Choose a Mountain Bike

Categories: Equipment.

I’m so confused!

Are you confused by the amount of choice in the mountain bike market? Don’t let the fear of making the wrong choice stop you making any choice at all. Let us help turn off the marketing noise and turn up the focus on what matters most when you choose a mountain bike.

Choose a mountain bike that fits you properly.

It doesn’t matter how good a deal the bike you are looking at may be otherwise, if it doesn’t fit you properly it is a bad deal.

So why is bike fit so important?

Getting the sizing right is vital when you choose a mountain bike

Image courtesy The Body Mechanic

The reason is an incorrect bike fit will at best be uncomfortable and become unpleasant to ride. As your fitness improves and you start doing longer distances it will get worse. Persisting with a poor fit can result in long term injury and damage. That will lead to time off the bike while you recover – thoroughly defeating the purpose of starting to ride.

Humans come in a vast array of different sizes and proportions. For some, simply using an on-line sizing calculator will be sufficient if they are lucky enough to be of average proportions. However, two people of the same height may have different arm and leg length proportions, such that one person who is say 180cm (5’11’) tall may be comfortable on a Medium frame and another will find it too cramped. Unless you have had some considerable experience you just won’t know.

How do I find out what size mountain bike to choose?

To get sizing in the right ballpark you are best served by going to a reputable specialist bicycle retailer in your local area. Get them to advise you on sizing and fitting for your first bike. It may cost a little more over buying sight unseen on the internet, but in the context of long term enjoyment it is a wise investment. Getting fitted should involve taking the bike for a test ride for 15-20 minutes. If they will not permit this, move onto the next shop.

More experienced and dedicated cyclists who do longer distances will usually have their bikes fitted to them by professional fitters. The more hours you spend in the saddle the more you will benefit from having the fit fine-tuned to suit your exact biomechanics.

For my next purchase, I will be going to the fitter first before I choose the bike. “Isn’t that putting the cart before the horse? How can that work?” I hear you ask. Excellent question! That will be the subject of an upcoming blog post when I catch up with Aaron Dunford of Fusion Peak at Fairlight in Sydney.

And no, it is not just for roadies. Mountain bikers can benefit hugely from a proper fitting, especially if they spend a lot of time in the saddle. I gained a significant lift in power output and comfort from a fitting session at The Body Mechanic prior to the 2013 edition of the Mont 24hr.

2: Decide what kind of riding you’d like to try

The kind of riding you plan to do is an essential input when you choose a mountain bike

Secondly, it would help to be aware of what discipline you are interested in. There are upwards of 7 different styles of mountain bike, specialised for different types of terrain and riding styles. A bike that does well for one style of riding is sometimes not suitable for other styles. You can check here for a description of the various styles of mountain biking.

3: Choose a mountain bike best suited to your intended riding

Take a look at our post on the different mountain bike disciplines, and then see what kind of riding is available in your area. You should also make an assessment of your skill level.

On the assumption you are a beginner entering mountain biking for the first time, and haven’t had the opportunity to grow into advanced bike-handling skills, the most common choice is a cross-country bike, usually one with front suspension only, known as a “hardtail”. This kind of bike is the one most commonly used on the smoother and more flowy trails that beginners prefer. The advantage of a hardtail bike is simplicity, light weight and pedalling efficiency. Because of the latter attribute, they are popular as general use or commuter bikes midweek and for the fun stuff in the dirt on the weekends.

Those who want to start with more advanced trails in mind will choose a dual suspension mountain bike. Mountain bikes with rear suspension as well as front suspension are usually more expensive. If they are at the same price, have lower quality components in order to meet the price point. Dual suspension bikes are also more difficult to pedal, especially on smooth surfaces such as roads. Suspension movement is prone to absorb pedalling effort. If you are planning on having the bike double as a commuter a hardtail is a better choice. Preferably you should choose a fork with a suspension lockout.

choose a mountain bike

If most of your riding wil be on dirt, if you have the budget a dual suspension bike can be a good choice. No, losing one side of the fork was not a cost-saving measure.

4: Choose equipment levels

Equipment levels depend largely on how much money you have to spend. For regular off-road use you would realistically be looking at $1,000 to $1,500 Australian dollars for a decent hardtail. For a dual suspension bike $2,500 to $3,000 will get you something sufficiently reliable and enjoyable for regular use. If your budget is less, I’d recommend you choose a mountain bike from the secondhand market rather than going for something cheaper brand new. You will need someone knowledgeable in your corner – see comments above regarding getting the sizing right. Preferably they will come along with you to inspect your new ride and spot any looming mechanical issues so you can bargain a bit harder if you need to.

You should also allow for some basic essential gear in your purchasing budget.

Lets turn our attention to the critical components.

Suspension forks

The Rockshox Judy is an outstanding entry level fork. Excellent choice when you choose a mountain bike.

The Rockshox Judy is an outstanding entry level fork. I’m excited they’ve brought it back.

When you choose a mountain bike, suspension fork quality is the next biggest influence on riding enjoyment after bike fit. At the entry level price point of around $1,000 to $1,200 Australian Dollars I recommend prioritising the fork quality over brakes and transmission. RST and Suntour are now making some nice gear at the middle and upper ends of their product range. Unfortunately, the entry level stuff that often appears at this price point I have not found to be up to the job.

It’s not the weight – everything at entry level is going to be heavy. What’s important is the ability to set sag correctly without having the fork blow through all its travel rolling off a kerb. Nor do you want it to be so firmly sprung that you can’t hang onto your bars over moderate trail chatter. You want enough damping so that the fork is not a pogo stick. You don’t want so much that it is going to pack down and eject you over the bars after a set of stutter bumps. It is not just a nice to have, it is a fundamental safety essential. Damping needs to be in the Goldilocks Zone – not too heavy and not too light, and with a reasonable range of adjustment for differences in rider weight.

Air or coil sprung?

Lighter air-sprung forks are definitely nice to have, but rare on entry level bikes. Coil forks are perfectly fine and at this point in time the market for good quality entry level coil forks seems to be owned by Rockshox. For other brands, seek the advice of experienced riders or ask a question here in the comments below.

Going up a level, for air forks there is a lot of healthy competition between the two main players Fox and Rockshox. Besides being lighter, air forks are more tunable.

Brakes

Hydraulic disc brakes are pretty much universal these days, and good quality brake sets are obtainable very cheaply. The two main rivals are SRAM/Avid and Shimano and both offer similar performance at the top level. At the entry level Shimano’s offerings provide a better user experience, and a superior level of reliability and performance in my opinion. I recommend Shinamo Deore as the minimum component level if your new bike is going to be used off-road regularly. If you have to choose between a good fork with Altus and a no-name fork and Deore, go with the good fork. You can upgrade disc brakes later much more cheaply than forks.

Transmission

Again, as for brakes, go for Shimano Deore as a minimum if you can fit it in the budget. The question then becomes 3×9, 2×10, 1×11 or 1×12?

Shimano doesn’t yet do 12-speed systems, and may not. They are the province of SRAM only at this time. I’m a bit of a cynic when it comes to 1x systems. I find either the range between high and low is lacking, or the gaps between gears is uncomfortably big. There are also issues with stability of gear selection when pedalling in reverse. You will sometimes need to do for part of a pedal stroke when negotiating trail obstacles. This is called “ratcheting your pedals”.

How steep is your terrain?

I have some reasonably steep gradients where I ride. Many exceed 20%, so I prefer the range and closeness of ratios available with 2x systems. If your terrain is reasonably flat these limitations will be less of a concern. If you are going to be riding road midweek as well as dirt on the weekend with the same bike then a 2x or 3x system will be preferred for versatility.

Be aware that most manufacturers fit a higher quality rear derailleur and skimp on the rest of the system. This is to make the bike look like a better deal while keeping more of your money in their pocket. It is actually the shifters that make the most difference to shifting performance. Make sure they are of sufficient quality – Shimano Deore as a preferable minimum.

With so many options available, choosing a mountain bike can be a confusing process.Wheel size

The debate about wheel size has been contentious among biking enthusiasts for some time. The three choices are 26″, 27.5″ and 29″. I’m going to ignore sensibilities and cut to the chase. Stick with 29″ unless you are going to straight to Downhill.

Why 29 inches?

Initially, 29ers were regarded as a weird cult inhabited mostly by those crazy single-speeders (riders with no gears). Then a few niche manufacturers started bringing out dual suspension XC race bikes with 29″ wheels. The smoother axle path over rough terrain meant they had a noticeable speed and comfort advantage in marathon races. Suddenly, the mainstream manufacturers all piled in.  They made a lot of money by making the older wheel size redundant and selling a lot of product to riders feeling the pressure to keep up with the Joneses. Nearly 30 years of mountain bike history with 26″ wheels was killed off, almost overnight.

Why not 27.5″?

It’s my view this has been an attempt at market manipulation.

Giant Bikes, facing limitations with its Maestro rear suspension design and the big wheels, tried to repeat the trick once more. They attempted to persuade the market that 27.5″ was the best of both worlds – 26″ agility with 29″ rolling ability.

They partially succeeded for a few years, and due to their position in the market others quickly followed. However, they were defeated by the physics of the axle path and sales have failed to match expectations. Geometry developments from those who stuck with 29ers has closed much of the agility gap. Giant have this year admitted defeat and brought out a new XC 29er dual suspension race bike. We might see them return to the sharp end of the World Cup XC field soon as a result.

Are  longer travel bikes a different case?

Possibly they are – the jury is still considering its verdict. Previously 26″ and later 27.5″ dominated the long suspension travel disciplines like Downhill and Enduro. This was due to the difficulties of matching suitable geometry, big wheels and big suspension in the same package. However, 27.5″ has come to dominate Downhill, and 29″ wheels are starting to show up for some events on the World Cup race circuit. Designers are starting to get their heads around the challenges.

I believe the physics of the axle path will again rule as designers refine geometry to solve the handling puzzle. We’re not quite there yet, though. 26″is now pretty much dead except for highly specialised markets like Dirt Jump and Observed Trials.

Tatbikes may be somethign to look at when you come to choose a mountain bikeYou’re so fat.

So, what about fatbikes and semi-fat bikes? I haven’t yet had an opportunity to spend quality time on either yet, but I want to, even if it’s only so I can form an informed opinion. One thing is certain: it will be interesting to see how the market develops.

Tyres

Good quality tyres are vital to enjoying mountain biking. Unfortunately most of what is sold on entry level bikes is rubbish as most buyers don’t pay tyres much attention. Fortunately it’s a relatively cheap fix and is not a show-stopper when you choose a mountain bike.
Keep what’s on there for commuting but invest in some decent rubber for riding on the dirt. I recommend a more aggressive, grippy tyre for the front as it is your control tyre, important for riding confidence. You can choose an easier rolling tyre on the rear, as the occasional sideways slip can be caught far more easily.

The best rubber for your local area is often terrain specific, so ask around locally. I like Schwalbe Rocket Ron on the front and Racing Ralph on the rear for racing, The grip and rolling resistance is great, wear not so much. For training I like a Specialized Ground Crontrol/Fastrak combination. They wear well, grip is good enough, and the sidewalls are reasonably cut resistant on our loose sandstone trails.

Other Essential Mountain Biking Gear

There are some basic bits and pieces that every biker needs to carry when they are out on the trail. This post walks you through what you need, and why.

5: Choose a mountain bike specialist shop

Work with your local bike shop for advice when choosing a bikeNow it’s time to visit a few internet forums and ask for bike shop recommendations. Then, go visit a few and do some test rides before making your final bike choice. You want to choose a shop whose team is interested in building a long term relationship with you. It’s not just about price, although that is important. It’s also about the quality of service they provide.

Taking time to fit you properly, putting you in touch with skills trainers and local riding groups are all good signs.

Offering to get you in the right size to try out if they don’t have it in stock is a very good sign, and should be rewarded. It is an indication they are interested in the long term relationship. Some shops will instead try to sell you what they have on the floor. Avoid these.

Final thoughts

Does that help? Is there anything we’ve missed? Do you disagree with our recommendations? Feel free to ask questions and leave comments below.

Comments

  1. Dean D'Alessandro

    Hi John
    I’m 49 y.o male new to MTB (well last time i did bmx i was a teen!)
    Live in BNE and ride the Jinker Track/Gap Creek (most rides here).
    Been on nine rides with a mate who intro me to MTB. Using his sons 26 Inch fuji hardtail until i decide if its for me.
    I’m keen to keep going..as it’s fun and challenging, very different to my road biking.
    I have had some crashes as obviously i’m a beginner/and lack confidence on some descents.
    I’m great at climbing but coming down..that’s a another story.
    Will get some lessons, but need a bike to do so.
    No 1 choice at present is a 2017 Scott Spark 960 (29er) $1,899 but also the Polygon D7 (27.5) $1,499\, both full sus bikes.
    Can you provide some guidance as to which bike or if i should look at something else.
    Am trying to keep $ to below $2k, given i will need lessons and new helmet and shoes etc.
    Kind regards
    Dean

    • John Hawkins

      Hi Dean,

      First let me apologise profusely for the delay in replying. Not really acceptable and I hope I am still in time to help inform your choice. For some reason there was no notification. 🙁

      Both will improve your descending as dual suspension provides a major improvement to stability on rough terrain. The choice of bike will be influenced by what you want to use it for. I really enjoy going fast for long distances, so naturally tend to gravitate towards short-travel 29ers. If, on the other hand, your preference is for descending and tackling more technical trails, sacrificing some of that speed for a bit more travel with slightly smaller wheels for agility then the Polygon is a sensible choice. A good question to answer is, what does your mate ride? Something similar would be a good bet. Or perhaps combine the best of both and get a 120mm 29er for a good all-rounder. I did this for a number of years and still had a blast at the occasional race back when 26ers were still dominant.

      That said, the Polygon has committed one of my pet peeves, which is not providing space for a drink bottle within the front triangle. As your rides lengthen with your improving fitness, you will need to start including carbs in your hydration mix to avoid the dreaded “bonk”. If you don’t, you start limiting your ability to safely complete longer rides, as trying to concentrate and negotiate singletrack while in a depleted state becomes challenging and unpleasant.

      The problem with putting carbs in your Camelbak bladder is the bladders need to be maintained and washed rigorously or they go manky really fast. I much prefer using a bottle for my carbs, carrying backups in my Camelbak. The bladder then contains plain water only, which does me for topping up in hot conditions and provding coverage incase we run overtime due to mechanicals. It also helps me monitor how much I’m tipping in the tank so to speak, so that I neither under-fuel and bonk or over-fuel and run short.

      Does that make sense? I’m happy to take your call if you’d prefer to talk in real time – details on the contact page.

      Best regards,

      John

Leave a Reply

Your email address will not be published. Required fields are marked *