A super lightweight aluminium upgrade from my regular ride, the Kinesis KR510, the Aithein represents a significant shift forward in race performance and styling.
The Aithein shares almost exactly the same geometry as the tried and tested KR510, allowing me to take a close look at how the detail and subtlety of the tailored tubing affects the feel of the ride.
Sold as a frameset only, the ‘up-scaled’ version of the complete bike as I rode it emphasised its lightweight potential. As you would expect, the low weight is its outstanding feature, giving the bike an immediate advantage up even the slightest drag, and as you accelerate away from junctions. Aside from the lightweight potential of the frameset as a complete build, the Aithein feels particularly lively and responsive when out of the saddle, giving an exceptionally dynamic ride. The lateral stiffness created by the triangulated down tube is responsible and really comes into its own when climbing.
On my local, sometimes steep lanes of Kent, the sideways rigidity of the Aithein combined with the bike’s lightness made mincemeat of even the steepest hills, giving me a quick and ready response with changing gradient and pace. The frameset has a frisky and playful feel when you point it uphill, and to my surprise I found that I was surmounting summits with ease that would normally leave me in my lowest gears and tugging on the bars.
The low weight is the Aithein’s outstanding feature, giving the bike an immediate advantage up even the slightest drag, and as you accelerate away from junctions
As a relatively light, slim built rider (around nine stone) I really enjoyed the potential this feature gave me for maximising my performance uphill. The front end of the bike was easy and natural to handle, making climbing out of the saddle relatively effortless, leaving some ‘headspace’ to play with change of pace, or to focus on the features of the gradient.
Moving from a seated to standing position brought an instantaneous response and almost whispered ‘attack’ in my ear as I shifted posture! Equally, with my weight balanced and centred nicely over the front end, I felt just as at home on long sustained climbs, dancing on the pedals for several minutes at a time with no discomfort or upper body fatigue. For repeated hill efforts, or in race situations with punchy climbs, this energy saving sensation would give lighter riders on the Aithein a distinct performance advantage.
Having said that, when descending I had to adjust my riding style to feel in control, hanging my body well over the back wheel to avoid the bike becoming too skitty. I felt that the nimble nature of the frame with a lightweight build needs an experienced pair of hands at the bars in tricky, slippery conditions where an over-reaction might cause problems. The straight fork and the tapered head tube gives immediate feedback and quite a twitchy quality that takes a little getting used to and might not be to everyone’s taste. In close, group/race situations, or when following wheels, the Aithein certainly feels very comfortable, allowing for easy and subtle adjustments, and rolling along smoothly tucked in tight behind another rider. Its tight geometry coupled with the stiffness at the bottom bracket make for exciting cornering capabilities and the potential for a sharp, powerful exit.
The stiffness of the frame created by the ‘core’ seat tube, which is so great when you are feeling lively, can be a little fatiguing on bumpy roads over more than a couple of hours
While the seated flat ride of the Aithein is great on fast smooth roads, it became a little uncomfortable on longer rides on rougher surfaces. The stiffness of the frame created by the ‘core’ seat tube which is so great when you are feeling lively can be a little fatiguing on bumpy roads over more than a couple of hours. Perhaps not helped by the 31.8mm seat post, you do feel the road surface coming up at you and together with the alertness needed to stay on top of this racer, this can be a little bit draining. Though the frame doesn’t pretend to be designed for comfort, for some this might make it difficult to ride the Aithein as an all-rounder if you regularly ride out for more than a couple of hours on bumpy roads.
Setting performance aside, the look and shape of this frameset is pretty classy, and its mix of traditional and modern has a kind of understated style that matches the ride nicely. I tested the anodized limited edition model, but as ever Kinesis UK have given the painted versions a unique twist with the colour way options of ‘SweetOrange’ and ‘SickGreen’ Metallic adding to the impact of the Aithein.
Overall both the look and the ride of this frame offers a refreshing and much needed alternative on the race frame market. Considering that the frame and fork retails for around £650, it offers the experienced rider a sporty and racy ride that will be difficult to match at that price point in any material. Given that the target market is likely to be working with a budget, I would have liked to test the frameset with a more moderately priced build, but I am confident that as a centre piece for a race bike the Aithein would enhance any competitive aspirations.
For me this frame is best suited to fast, hard and adventurous riding. Having said that, it would also provide a fast and fun commute for those that like to race their way to and from work. And if you are looking for a frameset to build up for local circuits and criteriums, the Aithein provides a stylish competitive ride at a very manageable price.
Size: 47, 50, 53, 56, 59
Colour: Black Anodized (limited); SickGreen metallic painted); SweetOrange (metallic painted)
Website: Kinesis UK
Distributor: Upgrade Bikes