Enve SES 4.5 wheelset review

The moment you take them out the box, the Enve SES 4.5 feel a little bit special. There’s something about them. Enve works in collaboration with the famous aerodynamicist Simon Smart, who has a strong background in Formula One. Smart has worked closely to optimise the shape of Enve's wheels for minimum drag and maximum speed.

>>> Buyer's guide to aero wheels (video)

SES stands for Smart Enve Systems and the number corresponds to the rim depth. However this can be a little misleading with the Enve SES 4.5 because they are actually 48mm and 56mm in depth, rather than the 40mm and 50mm you might expect.

>>> How much difference do aero wheels make? (video)

Our test set came equipped with Chris King hubs, which are absolutely sublime. Some sounds seem to really appeal to the human psyche, for me, the resonating roar of a Spitfire Rolls Royce Merlin engine is something very special indeed. While maybe not quite in the same league there is no doubting the ability of the Chris King free hub’s bee swarm like buzz to put a smile on the face of anyone riding one.

>>> Looking for your next cycling challenge? Check out this monster

One detail worth noting though is that the hubs are cup and cone, and do not have sealed cartridge bearings. This makes maintenance a little trickier for those who are not trained mechanics. The spoke nipples are internal, which although helps improve stiffness and lower weight, does make truing and spoke replacement trickier.

Aero Testing

I have ridden these wheelsets in as much varied terrain and conditions as possible. At times this has involved high mountains, rough lanes, and wet descents. In addition to this testing I also undertook an experiment to calculate the drag coefficient of the wheels with the help of engineer, Dan Bigham. This was also done at the same time, for several other leading wheel sets, to give a comparison.

For this the wheels were all ridden around a velodrome at a target power of 340-350w. 25mm Continental GP4000s II tyres were mounted on all the rims, with butyl inner tubes. Mavic skewers were used on all the wheels, with the levers orientated horizontally. The tyres were pumped to 100psi using a digital gauge.

Do you need aero wheels?

Power measurement was with PowerTap P1 pedals and the testbike was a Scott Plasma 3 TT bike, which allowed for a more constant rider position. Air temperature, air pressure, humidity, wind speed and wind direction were all recorded throughout the test, as was the combined system weight prior to each run. This data, along with the fit. files (the data files recorded to your Garmin) was in-putted into MatLab to calculate a CdA value (drag coefficient) for each wheel set.

As a control, a set of (non deep section) Mavic Ksyrium Elites were used to get a baseline reading. As expected the Enve SES 4.5 s showed a significant improvement over the Ksyriums.

Mavic Ksyrium Elite

System Cda – 0.250

Aero Watts at 40 kph – 210.5W

Enve SES 4.5

System Cda – 0.233

Aero Watts at 40 kph – 196.1W

Our Cda test suggested that the Enve SES 4.5 are considerably more aerodynamic than a standard box section rim, saving the rider 14 watts at 40kph over the baseline Mavic Ksyrium Elites. How do the Enve's perform against other leading wheels? They are the fastest wheels we have tested around the 40-50mm depth. As a comparison, the Mavic Cosmic Pro Carbon SL Cs were found to be 5 Watts slower at 40kph and the Zipp 303 NSWs were 3W slower at 40kph.

It is worth pointing out the the Enve SES 4.5 is slightly deeper than the Mavic and Zipps. The extra depth does not come at a weight penalty though. Despite the depth, the Enve SES 4.5 are light carbon clinchers that perform beautifully while climbing. The Chris King Hubs are sublime too. Although we were not able to separate bearing friction and rolling resistance from drag in our test, I suspect they may aid in making the Enve’s the faster. Another thing to consider is the wheel/tyre interface. The 25mm Continental GP4000s tyres sit flush and very well on the Enve SES 4.5, something that can be considered beneficial to aerodynamics.

 Video - Buyer's guide to aero wheels

Performance on the road

The new  Enve SES 4.5 features an updated brake track, with a filed surface and this offered improved stopping in wet and dry over the previous smooth Enve braking surface. It is a similar design solution to the grooved surface on Zipp's 'Showstopper' brake track. However, I found the new textured brake track ate brake pads at much faster rate. In addition, I did consistently experience loud screeching and brake fade when descending mountains. I should point out that I tested the Enve SES 4.5s in the French Alps and Cote d'Azur, descending climbs such as the Col de La Bonette and Col de Lombardie.

I found that to get the most out of the braking you have to set the pads up perfectly, with a slight toe in. You can get away with it on some wheels, but I found that any slight mis-alignment resulted in significant vibration and loud screaching on the Enve SES 4.5. This is in stark contrast the to the Mavic Cosmic Pro SL C carbon clinchers, on which the braking is excellent and the best we have experienced on carbon.

They may be very fast on the flat and going up hill, but noisy braking saps confidence, meaning that in my experience, you can go slower overall, because of the time lost on descents. For the majority of UK riding this is not a problem and they are dependable in cross winds. I just wouldn't recommend them for mountains.

For more information head over to www.saddleback.co.uk