The Latest Mojo
Ibis’s iconic Mojo infinity loop design is back, in the latest HD - the fifth iteration in this line. It is not a complete redesign of the HD4, but rather an in-depth refinement of that incredibly fun and capable bike. The good folks at this Santa Cruz, California based company have taken two year’s worth of feedback from you and their incredibly strong EWS race team, along with many countless hours of ride time and data collection, and created one of the lightest, best-performing bikes available (and it starts at a lower cost than you might think).
The bike itself looks very similar to the HD4, and when I received it there wasn’t much that jumped out as having changed. Having been a long-time owner of the HD4, I took the opportunity to build up my “Brown Pow” colored HD5 and ride it before inquiring as to what changes were made. Because I believe strongly that a bicycle’s performance is more than just the sum of its parts, I’d like to tell you my thoughts on how the bike rides before I delve into what changes were made.
The Bike that Never Lost its Mojo
I am 5’10;” I have a 5’10” wingspan and a 32” inseam. A pretty medium sized person. As such, Ibis sent me a medium HD5. I received the XT build kit with the Fox Factory suspension upgrade along with the phenomenal Ibis Logo Carbon wheel upgrade. Kitted out like this, it’s not an inexpensive bike, and runs a cool $7458. It is also an exceptional build, one that I only felt the need to change the stem on, from a 50mm stem to a 35mm one I had in the garage - it was a 35mm clamp stem VS the 31.8mm one it came with, so I also threw on my ANVL Mandrel handlebar.
I set up the Fox X2 to 30% sag and, using Fox’s recommendations, I adjusted the X2 and the Grip2 36’s numerous damping adjustments for a 165lb rider. Even just in the parking lot, the rebound on both the fork and shock felt a bit fast compared to how I usually set up my bike, so I added a few clicks of rebound damping.
During my setup I did measure the fork, noticing that it was set at 170mm instead of the HD4’s 160mm. Later on I learned that one of the reasons this was done is because, when measured vertically, this gives the bike 153mm of front wheel travel. This exactly matches the rear wheel’s 153mm of vertical travel. A perfectly balanced bike!
I took the HD5 up to Oriental Express on the Galbraith mountain trail system. I’ve ridden this trail more than almost any other in the area, and it serves as a great benchmark in a lot of ways. To get there you must climb some mildly technical singletrack, and the trail itself has portions of fast flow trail, a decent amount of more technical downhill, and just because, some small jumps.
Despite my stubborn ideal that a few pounds of bike shouldn’t make a difference, that I should just lose a pound or two and save $2,000, the reality is that two pounds is a noticeable difference on a bike. That doesn’t keep Rich from whooping my butt up the hill on his 36lb, CushCore shod aluminum Sentinel, but it does make a difference. The HD5 is a light bike (as it turns out, 30 lbs). And that is not only because it had a nice XT build and carbon wheels. My Santa Cruz Megatower has a lighter build kit, and is two pounds heavier. Light bikes are something Ibis has a reputation for, and they’ve upheld that reputation with this bike.
That made me want to crank hard on the bike, which was easy because Dave Weagle’s DW-link has a finely tuned amount of anti-squat (right at 100% through almost all of the travel), so essentially doesn’t bob. It’s not a Ripley, but the HD5 is an exceptionally efficient climber despite that 170mm fork.
It is also a very comfortable climber. By the looks of the bike, I already knew it was longer than my medium HD4, but it didn’t feel it while climbing. I had a comfy, up-right posture, and didn’t feel like my front wheel wanted to wander at all. That immediately pointed to a steeper seat angle than my HD4, and later on I was happy to find that it was indeed now 76 degrees instead of the previous 74.
After getting off the singletrack portion of my ascent and on to the logging road, I threw the X2’s climb switch on to see if it felt different, and other than a brief portion of over-the-top, stand up pedalling, did not notice any change in my perceived efficiency.
Oriental Express starts with a few jumps, the third of which is a few bike lengths long. I pushed through the first too, and pulled on the third. The HD4 was an exceptionally playful little bike, and the HD5 is right there with it. Part of that is the bike’s weight, and another part is the 27.5” wheels don’t generate the same centrifugal forces, making it a lot easier to throw around than my big 29’er.
I boosted that jump and entered a new section of trail that features a handful of tight little turns. Again, the smaller wheels and light weight let me pull the bike through them easily, throwing my weight towards the exit while moving the bike around the turn with little effort.
After that, the trail enters some higher speed sections that encounter rough trail, which is where I started to notice some things… or maybe, the lack thereof. Bumps. Normally very present and obvious, they were nowhere to be felt. I could see them on the trail, but by the time they were under the bike, I wasn’t feeling them.
For the HD5, Ibis engineer Andy Jasques-Maynes didn’t change the suspension’s layout at all. He did incorporate the same lower link that was introduced on the Ripmo and is now on the Ripley as well, which spins on bushings instead of bearings, but the leverage rate and everything else is the same.
With that variable controlled, what Andy did instead was to focus on the suspension itself. He used a data collection system made by Motion Instruments to monitor how fast and when the suspension was compressing and rebounding, and really optimize how it was tuned around the bike itself.
He already had a fairly light compression tune, allowing the wheels to easily move out of the way of bumps in the trail, but he found that he kept going lighter and lighter on the rebound damping - that is, making it faster and faster. The purpose of suspension is to maintain the wheel’s traction, and he found that he needed higher rebound speeds to get that wheel back on the ground and keep the bike tracking the ground.
In running the shock at these speeds, he also found that he was approaching the end of the usable spectrum of rebound adjustment on his Grip2 fork. Not fully open, but getting to where something would have to change in order to allow a wide range of riders a fully adjustable fork.
It became apparent that to match the tune of the rear shock, they’d need a lighter rebound tune on the fork. He and the folks at Ibis approached Fox about this, and the “Traction Tune” was born.
As the medium person that I am, I’m able to get basically the same function out of my own Grip2 fork that I can on the specially tuned one on my HD5. It’s just a few clicks further out. But especially for lighter riders, this design makes for far more usable suspension, both front and rear. No longer will 140 lb rider have to keep their rebound damping all the way open to get the rebound speeds they need. And personally, I’ve found that I’ve been running my rebound damping slower than it needed to be to make the suspension as active as possible.
Now, this is not an end-all-be-all change. The speeds for a given setting are generally a little faster, but because these shocks have so much adjustment, if you still want it slow, you’ll get there. It just makes the range more usable for more people. Andy’s set up suggestion for rebound is this: leave high speed rebound all the way open. Start low your low speed rebound adjustment in middle, and adjust from there.
Odds and Ends
The HD5 is a phenomenal successor to the HD4. Aside from the routine matters like making it longer and slacker, Ibis has kept the bike comfortable to pedal by steepening the seat-tube angle. It also can now accept a longer dropper across all sizes, allowing even smaller riders to run a 150mm post. They’ve re-assessed their carbon lay-up and made the bike stiffer and a hair lighter (aided by the new lower suspension link). They’ve even fit the bike with usable water bottle mounts.
There’s other smart features like internally routed hoses and housing that you don’t have to go fishing for, and a new little mud guard above the lower link that will keep dirt and mud out of hard to reach spaces. The molded rubber chain-guard on the chainstay is wider than it was on the HD4, keeping noise down to a whisper. It is in fact one of the quietest bikes I can remember riding. The main thing you hear as you mob down the trail is the suspension dampers breathing in and out.
I loved my HD4, but there were a small handful of things I always wished were different. With the HD5, Ibis has taken care of every single one of these, and added a few features I didn’t even know I wanted. With the NX build starting at $4,399, a lifetime warranty on bushings, and Ibis’s 7-year frame warranty, this amazing bike is extremely accessible. If you’re fortunate enough to be able to get on one, it will bring you mountains of fun. If you have any more questions about it, don’t hesitate to reach out to us at 844-FANATIK, or shoot us an email at firstname.lastname@example.org.
Happy trails - Dan at Fanatik
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