The K2 Thraxis is K2′s super high end boot that offers the most in heel lift suppression. It does it with some sacrifice to adjustability but it’s one responsive Tripple BOA boot. Yep 3 BOA Coils. One for the upper along with some of the ankle, one for the lower and one for the liner.
Flex: This is a pretty stiff boot and it’s right up there with any other stiff boot in the industry.
Comfort: K2 makes big bulky but comfortable boots. They are super comfortable and are right there at the top when it comes to making your foot feel at home in a new boot. Unlike some BOA boots K2 makes a very dense liner to shield you from the pressure points a boa lacing system can cause if you tighten it up really tight. The draw back of this is the footprint is hard to reduce like some other companies do. The Thraxis has 1 BOA for the liner, 1 BOA for the upper and 1 BOA for the lower. Heat moldable liners really make a difference so that is a nice bonus.
Heel Hold: If you are worried about heel hold then the K2 Thraxis will lock in even a smaller heel/ankle and keep you secure. It starts with the BOA system in the liner and then goes to the double boa system that overlaps on the ankle on the outside. There aren’t many boots that can lock you in like this.
Adjustability: You would think with 3 BOA’s that the K2 Thraxis is very adjustable but in reality there isn’t much separation between the upper and lower BOA’s. It’s quick on and off but both BOA’s overlap on the ankle so there isn’t much difference between upper an lower. So you sacrifice upper and lower adjustability but you get lot’s of heel hold in return.
Flex Retention: The K2 Thraxis doesn’t have much ankle articulation going on to retain the flex but they do have their own unique tech that does just as good or better. They have put a urethane material throughout the spine that works about half way through the boot that retains it’s flex the same on day 100 as it does with day 1. The front part of the boot will break down like all boots and it will pack out a bit but the overall flex will hang in there for a long time.
Response: Very quick and responsive and you would expect this for the Thraxis Flex.
Traction: No complaints here. Vibram is just bad ass and works well anywhere from the parking lot to a rocky frozen peak.
Shock Absorption: K2’s harshmellow dampening system is a great system and it can handle a flat landing for sure. It’s a nice cushy feel when it comes to day in day out riding and with the Thraxis you feel like your foot is very well protected.
So if you are all about heel hold and response and don’t care too much about having a reduced footprint then the K2 Thraxis could work well for you.
The 2011 and 2012 K2 Thraxis are pretty similar barring a few minor adjustments and both are great boots….especially for their time.
The 2013 K2 Thraxis has one big change to the build that makes this a much better boot. The addition of Urethane throughout most of the boots frame is a great idea. It’s a smart approach to dealing with preservation of the flex. It’s like having a lot of ankle articulation. This is for sure the call over the older models