Intended Use: xc, trail, all mountain
Rider: 6’2”, 205 lbs., athletic, technically proficient, modestly fast and relatively fluid.
Test Location: Colorado Front Range. Steep, fast, rough, rocky trails. Generally in dry, dusty, loose over hardpack, pebbly terrain, but plenty of smooth buffed trail and dirt / loam.
Test Bike: 2010 Giant Reign X, 170mm travel, XT build kit, Mavic Crossmax SX wheelset, 32 lbs. total
Duration of test: 20+ days of riding.
Chassis: TheX-Fusion Vengeance RC offers 160mm of air sprung travel and a 20mm thru-axle. It is offered in both a tapered 1.5->1.125″ and a straight 1.125″ version. This test is on the 1.125″ straight steer tube.
I found the Vengeance noticeably stiffer than my former Rockshox Lyrik tapered steer tube and at least as stiff as the Marzocchi 55 RC3 Ti Tapered. The Vengeance fork only weighs 40g more than the Lyrik, and approximately 200g less than the equivalent Marzocchi. The Vengeance chassis has a traditional bolt-on (rather than a quick release) axle, which is a bit of a shame, but has already been addressed for 2012 and updated to a quick release 20mm axle.
The Vengeance fork is 5mm longer in axle to crown length as compared to a Lyrik of the equivalent length, which was not noticeable on trail. I did find the air spring slightly too linear and was blowing through the travel on larger hits. To address this, I added 10-15ml of fork oil to the air spring and that nicely added progression to the fork. After this modification, the fork has a nice ramp up toward the end of its stroke, and rides exactly how I wished it would.
Damping: The product is offered in 2 trims: the RC (rebound, compression, air spring) and the HLR (high-speed compression, low speed compression, rebound, air spring). I opted to test the RC trim line, as both forks feature a tuneable shim-stack damper circuit. The HLR fork adjusts the spring preload on the shimstack, but the tradeoff is that this adjustment gives up a slight amount of sensitivity to the RC at lower shaft speeds (i.e. stutter/brake bumps). I found that the spring preload on the RC is tuned properly and did not need micro-adjusting.
All X-Fusion forks feature ridiculously smooth, plush, and sensitive suspension, and yet, the suspension is controlled. Once I had set the low speed compression at the correct level, I never felt the fork dive. Since the fork is so incredibly smooth, I could run more compression than I normally might, and the fork never felt harsh. This equates to having more useable suspension and more acceleration out of corners and berms, better speed management with the front brake, and more pop off the lips of jumps.
Set-Up: Each click on the rebound and compression knobs offer a small but noticeable adjustment. I did not find myself in-between indents, and settled all adjustments to the middle of their ranges, so there is plenty of up and down on each to suit most needs. The fork was very easy to dial-in on my first ride, and I have not felt compelled to experiment more than 1 or 2 clicks in either direction just to confirm that I was in the right place.
Trail Feel: The X-Fusion fork is perfectly smooth, and perhaps the smoothest friction-free fork on the market. It is incredible, really, to be able to compare this stock, out-of-the-box fork to pimped out, aftermarket-tuned Rockshox and Marzocchi offerings (never mind the stock iterations from both of these brands). The X-Fusion fork really is in its own class in this regard. I found the fork quite easy to tune to my preferences and it took literally one ride to feel totally at home on this fork.
Summary: This fork is, in my opinion, THE class of the trail bike suspension fork market. Its weight is comparable to the competition, it is a couple hundred dollars less expensive, it is very adjustable and easily setup, and it offers the highest quality suspension of any 160-180mm fork on the planet. (Yeah, you might want to go back and read that sentence again.) It is also as stiff or stiffer than the competition and offers more precise handling in the front end. The only gripe I have is related to the spec of a bolt on the 20mm axle, rather than Quick release axle, but this has already been addressed for 2012.
All in all, this is the best trail bike fork currently on the market in all aspects of its construction.