What are the important parameters for an MTB

andy_welch

One of the problems faced by anybody who is new to any field is cutting through the jargon and marketing speak to decide what's important. Mountain bikes seem to be particularly difficult in this respect due to the fragmentation into styles of riding that are at best poorly defined and at worst just marketing guff.

The general advice to test ride anything you are interested in sounds fine, but actually getting a meaningful test ride is at best difficult and in some cases (e.g. Boardman or Canyon bikes) pretty much impossible. So we need some way to at least organise the bikes into meaningful groups so that we can relate what test rides we can arrange to other bikes. But this is made harder by the lack of any standardisation in the way they are described.

For example, as a newcomer to the field I've been looking at full suss bikes. I've heard of Giant before so I look at their bikes and see that they have an Anthem, for XC and a Trance for more general trail riding. Canyon and Boardman also seem to crop up near the top of everyone's value for money charts and I see that Canyon do an XC and an AM bike and the Boardmans are also described as XC.

So, based on the descriptions I'd expect the Canyon XC and Boardman to be similar to an Anthem (all XC) and the Canyon AM to be more like a Trance. However, a closer look at the specs and geometry shows that the Canyon XC and Boardman bikes have a head angle and travel that is much closer to the Trance !

To make things more confusing there are simple things that you can change on a bike (e.g, bars, stem, saddle position, suspension setup etc) that I know from experience can totally transform how a bike feels.

All of this is, as I say, very confusing to a newcomer. So, I wonder if we could come up with a list of the most important features to get right and the important parameters to look for to decide whether a bike will suit you. I guess a good place to start is with the question "what will be most expensive to fix if you get it wrong?". I'll start with.

1. Wheel size. Whether we like it or not there is now a choice to be made and if you get it "wrong" you'll need to change frame, forks and wheels at least.

2. Geometry (which I guess has to include travel). Get this wrong and you will need a new frame and forks. Important parameters here are (I'd say) travel and head angle. Then the basic size (although you can do a lot with different stems etc to tune this).

3. Full suss vs hard tail. If you've got point 2 right you'd "only" be looking at a new frame to fix this.

After that it probably just comes down to softer things like: whether you like the look of the bike, how reliable the make is, how easy it will be to get things fixed (e.g. warranty issues).

Cheers,

Andy

simonp123

I’m with you on this one, I am not particularly a newbie and it can still be overwhelming when looking to buy new. You cannot beat a test-ride for sure BUT unless it is the same spec model as you are looking to buy there is limited use to it, other than checking sizes. Often you are offered a ride on a high-ish spec model where the forks and shock (on a full suss) will be different to what you may be looking at and so a test ride will tell you little.
As I found with my Stumpjumper, the changing of components and correct suspension setup can almost completely transform the characteristic of a bike, though obviously not the geometry.

It is even more difficult if, like me, you are looking to buy a frame and fit components you have, the geometry weight and construction characteristics become the primary bits that you are interested in.

benpinnick

Beyond the valid points made, I always advise that people buy their bikes based on a cost to replace scale - i.e. buy for the bits you really don't want to replace as they cost alot. These are, in decending order of importance:

Frame
Forks
Wheels*
Brakes
Cranks
Tyres
Shifters
Bars
Rear mech
Front Mech

* Wheels on most bikes are fairly out of whack with the rest of the spec, as they can be rebadged/unbranded but still look nice. You would not buy a bike without a 'named' fork, most likely, but own-brand wheels seem to be very common. Hence while they are high in the cost to replace list, they get a special mention as a likely to be substandard for the rest of the spec item, worth considering a replacement.

Contact points should be considered pretty much throw away IMHO (Grips and Saddle in particular), and pedals are normally just that, throw away items. They all get you going, but you need to look for what is best for you straight away, as they radically change the comfort of the ride. Cassette and chain will wear, so don't worry about those too much.

andy_welch

Good points there.

As somebody coming to mountain biking from the road, suspension is certainly the complicating factor. I think (given a bit of experience and knowledge) that it ought to be possible to predict roughly how a bike will feel from the geometry (and bearing in mind the bits that can be changed cheaply), but suspension messes this up as it can totally change the feel of a bike. In fact it seems that you are better off taking time to set up your suspension properly than spending lots more on a supposedly better bike that isn't set up right for you, which is a good thing I guess.

Buying based on the bits that are most expensive to replace sounds like a very good approach. Wheels have always surprised me as well. I learnt how to build my own many years ago. It's a bit time consuming, but you can do it in front of the telly, the kit is cheap and once you know how to do it it's easy to true them up again when you need to. I stopped doing this for my summer road bike when when we started getting wheels with minimal spoke counts and fancy patterns. But I'm still running the wheels that I built on a couple of bikes that have done thousands of miles and MTB wheels still seem to be simple 32 spoke built with a standard 3X pattern. When you look at the cost of even quite nice hubs, rims and spokes the factory built wheels do start to look rather expensive.

Cheers,

Andy

simonp123

I have been surprised how heavy some reasonably well specced bikes are compared to my Stumpy, and given that the bare frame weights are very similar I can only assume that the weight is in the wheels. It does seem mad to me to fit lighter mechs etc but keep a weight on one of the areas where weight saving would be of most benefit i.e, rolling weight.

I would place wheels high on the list of things that you may soon want to replace on a lot of bikes.

nicklouse

simonp123 wrote:

I have been surprised how heavy some reasonably well specced bikes are compared to my Stumpy, and given that the bare frame weights are very similar I can only assume that the weight is in the wheels. It does seem mad to me to fit lighter mechs etc but keep a weight on one of the areas where weight saving would be of most benefit i.e, rolling weight.

I would place wheels high on the list of things that you may soon want to replace on a lot of bikes.

weight is also relative to the designed use of the frame. specs can be the "same" but the use not.