The HD5 is an entirely new bike, but Ibis did not start with a blank slate. Instead, they took the phenomenal HD4, which has been ridden by Ibis's highly successful EWS enduro race team for several years, and refined it into a modern masterpiece.
Because they didn’t tweak the DW-Link suspension design, Ibis engineers were able to instead focus their efforts on optimizing the suspension components themselves. Working with Fox, they’ve developed their own “Traction Tune.” This lighter-than-normal damper tune allows a larger segment of users to find the light, active feel that they want to get out of their bike, and makes for one of the smoothest rides we’ve ever experienced.
With the HD5 Ibis has adjusted the geometry to make the bike more capable both descending and ascending. They have lengthened the reach of the bike by around 15mm per size, slackened out the headtube by almost a degree, increased the front suspension to 170mm, and steepened the seat-tube angle from 74 to 76 degrees. A large HD4 has the same reach as a medium HD5, but because of the steeper seat angle you won't feel more stretched out during seated pedaling. Your weight is also further forward, so despite the slacker head angle, your front wheel doesn’t wander while climbing. The longer front-center and slacker head-angle also results in a longer wheelbase than the HD4, which makes the bike more stable at speed.