Review Cube Reaction Mountain bike

This is not a comparative review by a professional bike journalist where someone has had the pleasure or riding a dozen bikes with similar specifications and price range.  You can read that here (albeit in German), but if you don't want to pay €2 for that, I can tell you that this bike got the best score of all the ones they looked at. My comparison is going to be primarily with an 8-year-old fully from Trek, simply because that was my previous bike, as well as a smattering of impressions from various bikes leant and hired over the years. So in that sense, this is as much about what has changed (or not) in the past few years as any specific model.


This review is about the 2015 version of the Cube Reaction mountain bike. The Reaction comes in eight different varieties, split by wheel size (29 inch and 27.5", 26"not being on offer), Aluminium (HPA) and carbon (GTC) frames and Pro, Race, SL and SLT with varying components fitted.  They all have Shimano XT for the drive train, with the main differences being in the forks and wheels - and therefore weight, though they are all about 11 kg with a difference of only plus or minus a few hundred grams, which no normal person will be able to feel on the trail. Incidentally, it always strikes me a bizarre that manufacturers quote both weights and prices of mountain bikes without pedals, like the bike will somehow work without pedals.

I have the Pro version of the Reaction, which means it has the possibility of 27.5 inch Fulcrum Red66 wheels which are slightly heavier than the Red 44 wheels on the SL version and forks from Manitou, rather than Fox.


I spent ages reading articles about the merits of different wheel sizes. This one on bike radar explains the basic pros and cons clearly. 26" wheels are lighter and more manoeuvrable, 29" bikes are more stable and bounce over obstacles more easily.  I came to the conclusion that for someone my size (1.72 m), 27.5" (a.k.a. 650B) was the ideal compromise. The only problem was that I am left was a legacy of a shed full of 26" tyres of various types that will be enough to last my daughter's bike until the end of time and at least it is no problem to use 26" inner tubes on slightly larger wheels. So do 27.5 wheels feel different than 26"? If I'm paying attention, I can notice the difference.  Although the angle of attack is only less than 5 degrees different, I do notice that I can roll over branches that are just that bit bigger than on my old bike before needing to hop and going downhill there is a bit more stability.  Maybe there is slightly less manoeuvrability, but that is not really noticeable and the effects on acceleration can only be determined when comparing bikes with the same weight.

Forks and suspension

The largest difference between the 'Pro' and 'SL' versions of the Cube Reaction is the forks; Manitou Marvel TS Air versus Fox 32 float (both 100 mm). And €400. The Fox Float is a famously good fork. Is the €400 just for the name 'Fox', or is it really worth it? I must say, in the beginning, I was a bit doubtful. The Manitou did not seem to be doing much, despite fiddling with the amount of air in it. However, then I read in the manual that it doesn't start working properly until it has been ridden for 20 hours and soon after that I discovered that there was a rebound speed control hidden underneath one arm (as well as being not mentioned in the manual!) which was set to the extremely slow position. So it was not surprising that in the beginning, it did not seem to do much and indeed after a few hours, it began to get much more supple. It will probably take a bit more fiddling to get the air pressure and rebound just right for me, but I must say that it does a fine job of smoothing out the roots and rocks in the way. I'm happy I did not fork out (ha!) the extra cash. A carbon frame is supposed to filter out fine judder from the ground, and this one also seems to have a good compromise between stiffness and vibration absorption.

Of course, a huge difference between this bike and my old Trek is the lack of rear suspension. Together with the carbon frame, that means that it is 2 kg lighter, and quite a lot lighter in terms of euros as well. The main reason that I got a hardtail this time was that the fully gave a smoother ride, which (in retrospect) took some of the fun out of mountain biking (see here for more on that). When I got the Trek I was struck not only by how I could charge over impossible terrain like Deschampsia hummocks but also how I could get up steep sandy slopes that I could not manage before, because the back wheel stayed in contact with the ground.  So was a bit nervous about my decision, would the hardtail mean that I would be having problems in those places?  I guess what I hadn't fully realised was that the Trek was not only a good fully, but also in all-round terms better than the beginners' mountain bike that I had before it.  So it performed better in various situations not only because of its rear suspension, but also because it was better in all sorts of other ways. So far, my fears about the lack of traction of the Cube hard tail have proved unfounded and it has bounded all over the woods here in Holland and on holiday in Germany with no problems.


 Much more than the wheel size, the handlebars, with a massive 740 mm width, felt really strange at first to me.  Just getting it in and out of the shed without carving holes in the door as I scraped past was quite difficult. The door is not that narrow, but it must be said that there is a certain amount of junk the in shed which means it does not open all the way. Shortly after getting the bike, we went on holiday to the Eifel in Germany, which is a great area for mountain biking, with considerably more hills than round here (though it must be said, not many places have less hills than Holland). I took a hacksaw with me with the intention of sawing them off to a sensible length as soon as I had determined what that should be. The wisdom of the internet seemed to be that you should do a press-up, measuring the distance between your hands and that is how wide they should also be on the bike.  There seemed to be some logic in that, so despite not having done a press-up for years, if not decades, I made the measurement (with some help, I guess that is pretty much impossible on your own). To my great astonishment, the tape measure indicated that I only needed to take off 1 cm on each end.  Being naturally reluctant to take a saw to my brand new bike, I decided to see if I could get used to the new size, and to my great surprise that in fact happened. Even really narrow winding paths (like the delightful singletrack below) turned out to be wider than my shed door, and I avoided knocking into trees on all occasions. It was indeed quite comfortable to have my arms that far apart and maybe even helped with the steering.

 Narrow track

 The steering is certainly worth mentioning.  In mountain bike magazines they are always talking about how certain bikes just go the direction you point them.  I must admit, I never understood that phrase.  Of course, they do, that is the whole point of that bit you can turn. But now I understand and also realise that there is indeed not a good way of describing this.  I guess it is a combination of the wide handlebars, good headset, firm forks and great thick QR15 front axle, but indeed the steering is notably sharp and precise.  It does go where you point it.


 A lot of Cube bikes are painted with astonishingly garish colours, which would look more at home in a sandpit alongside a toddler's plastic bricks that in the woods.  I would not select a bike purely on its looks, but on the other hand, I also would not want a bike which looked dreadful.  Fortunately, this model has a more subtle combination of grey and white, which looks very good and some blue accents which add to the appearance without being too bright.

Cube Reaction

The cables for the gears are nicely integrated inside the frame, but the hydraulic 'cable' for the rear brake is attached to the outside of the down tube. The frame has a fairly upright geometry (compared to my old fully), placing the rider more over the handlebars, with a head tube angle of 70 degrees. I guess that means it is a bike more aimed at going up hills than doing anything too frightening in the way of rushing down across boulder gardens, and it is certainly so that it really flew up the steep hills on holiday, for instance managing a 1200 height meter ride without completely destroying me for the rest of the day.


Someone who has just invested several decades of his pocket money in a bright shiny new toy is hardly going to admit to anyone, least of all himself, if all did not come up to expectations, let alone write an entirely objective review. Nevertheless, I can genuinely say that the Cube Reaction really is a super-good bike.