The Crankbrothers’ Synthesis tuned wheelset is now available in aluminium, for XC/Trail, Enduro and E-Bike disciplines. The Synthesis concept, originally materialized in carbon, is devised around a stiff rear wheel and a more compliant front wheel. Designers Mello Bouwmeester and Jason Schiers reckon this platform respects the differing roles of, and loads carried by, a front and rear wheel. We tested the Crankbrothers’ Synthesis Alloy Enduro Wheelset on our home trails of Innerleithen, Scotland.
Feature image by Robyn Wilkinson
Crankbrothers’ Synthesis E Alloy Wheelset
We have reviewed the 29″ Synthesis E Alloy Wheelset on Industry Nine’s 1/1 hub with 4° engagement. Crankbrothers also offer a Synthesis Alloy Wheelset with Crankbrothers’ standard hubset, made by i9 on their behalf. It is considerably cheaper than the 1/1 hubset, but is also heavier, offering 17° engagement. That said, Crankbrothers sell the front and rear wheels separately, so you invest in the rapid engagement i9 hub, and save a bit of money on the front hub. The wheels were intended for a Cannondale Jekyll 29 enduro bike, thus Crankbrothers kindly redished the rear wheel as per Cannondale’s specifications for an even spoke length, tension and bracing angle.
Crankbrothers achieve different levels of stiffness in the Synthesis wheelset, front to back, by altering a number of factors: Number of spokes, spoke weight, spoke tension, rim widths and rim thickness. Learn more about that here. Stick around to hear how we got on with the Synthesis Enduro wheels over our 3 week test period.
First Ride Impressions
We paired the Crankbrothers’ Synthesis Alloy Enduro Wheelset with a set of Maxxis Assegai EXO+ 2.5″ Wide Tyres, optimised for 30-35mm internal width rims. We ran a tubeless setup, with tyre pressures around the 15 psi mark up front, and around 18-20 psi out back. The tyres went on with worrying ease, and seated and sealed with the use of an Airshot with no issues.
Our Innerleithen trails are, for the most part, low in speed, steep and sloppy. Hence the low tyre pressures. The different internal rim widths gave rise to ever so slightly differing tyre profiles. The Assegai measures 63mm from outside knob to outside knob on the front wheel, and 64mm across on the rear wheel. This produces a more squared off profile on the rear wheel, with a more rounded profile up front. It should be noted that, strictly speaking, the Assegai 2.5″ is optimized for 30-35mm rim widths,. Our Crankbrothers Synthesis rear wheel sits just outside of this range, at 29.5mm internal.
The wheels feel smooth, stable, comfortable, and when pushing hard, the difference in compliance between the front and rear is actually noticeable. With a 32 spoke count, the Synthesis E alloy rear wheel is probably the stiffest aluminium rear wheel i’ve ever ridden. But it isn’t too stiff. I definitely prefer its ride feel to the stiffer carbon wheelset I rode previously. It tracks superbly through corners, following true the line picked by the compliant front wheel. The Industry Nine 1/1 is fast to pick up, and makes a not-insignificant amount of noise. You can almost tell how fast you’re going, or not going, from its whir.
Since running the wheelset I’ve noticed a drop in upper body fatigue, arm pump and the likes. This could be a result of the compliance of the front wheel, dampening vibrations and transferring less impact to my arms, but it could equally be a result of an increase in press-ups and time on the Descent Master. Hard to tell, really. Either way, with a well-damped FOX 36 Performance Elite fork, the ride has been a very comfortable one. Through rough rock gardens, the front wheel’s compliance makes it pretty forgiving when my line choice is sub optimal. Rather than getting pinged off the trail entirely, the front wheel finds its way through obstacles without too much drama.
In three weeks of riding the Synthesis Alloy wheelset almost every day, I punctured just once. The rear tyre took a pinch flat on a small-to-medium size boulder scree trail. The rims have taken a fair beating and, to their credit, they’ve taken it very well. The test period has remained ding-free, despite my best efforts. They’ve taken some rock hits of course, but come away almost unscathed, with just a few scratches to speak of. This, I was impressed with.
I have only one complaint, and it isn’t necessarily specific to the Synthesis Alloy wheelset. Though it seems to be the fashion, I’m not entirely convinced by the trend towards wider rim widths. Personally, I find the wider rim profile on the front wheel actually results in less precision and reduced grip, certainly with a 2.5″ wide tyre. The contact patch shape broadens such that, the front wheel starts to feel more likely to “wash out”, especially through flat corners.
Thus, I feel a 31.5mm internal width rim up front is a little overkill. Perhaps this isn’t such an issue for heavier riders. I prefer a narrower rim and narrower tyre up front, which allows me to, or at least gives me the confidence to, carve corners tighter in order to set up earlier for the next one. Perhaps I should consider the Crankbrothers’ Iodine wheelset.