24 November 2009

bikefix Second Look: Continental Mountain King 26x2.4in UST tire

Aside from being one of the friendliest, most enthusiastic riders we know, Juan Pablo is also an accomplished off-road triathlete, one with the sort of bike handling skills few tri folks posses. Here's his review of Continental's 2.4in Mountain King UST Tire:

I have used this tire on my front wheel (26) off and on for over 18 months. Its latest assignment was on my front wheel at this year's Xterra World Championships in Maui.

My first experience with the Mountain King was in Moab. From Slick Rock to Amasa back, the tire impressed with its grip in slick rock. I was expecting the tall knobs to flex and wobble, but that was hardly the case. The tire was planted and predictable. On the loose and sandy terrain it offered the grip that I was expecting and more. The tire felt light when taking into account its size and when compared to UST tires of similar girth [the Mountain King is nominally a 2.4 but bikefix have measured it at right around 2.2in wide]. It did seem narrower than I expected but the tire has appeared to ‘grow’ a bit over time.

This trip to Moab included some particularly aggressive riding companions that in turn encouraged some very aggressive pursuits. However the tire showed no damage to other than normal wear on the knobs. Surprisingly no knobs where torn or missing- this has been a common occurrence in my experience with tall-knobbed tires, perhaps avoided in part by the knobs’ pyramid-like construction.

I also used the tire repeatedly in New Mexico and experienced Velcro-like performance on loose-over-hardpack and sandy terrain. I consider myself a ‘carver’ and enjoy carrying speed on tight turns, this tire up front makes me question how much more speed can I actually carry though the turn.

In Telluride I rode in loamy conditions with excellent traction; however I reduced pressure to make sure that the Mountain King would clean itself of packed mud. I could see how a big tire like this could cause problems in stickier clay though. I have yet to test it in the infamous Hawaiian clay, but will do soon enough as rainfall will increase in the fall and winter months here on Maui.

My next experience with the tire came as I was preparing for the 2009 Xterra World Championships. In the past (2005) the course has left me with un-pluggable flats on UST tires, and this is the same for everyone, from [three time Xterra world champion] Conrad Stoltz down. The a’a (Hawaiian name for this a particular type of lava) is unpredictably sharp and it litters the south part of the MTB course (due to recent lava flows – 400 years old or so), the place where most of the course’s descending takes place. All of the race's climbing takes place on the North side of the course with a little more dirt than rocks.

In preparation for Worlds, I tested several tires. Basically I rode on a’a with the intention of puncturing a tire. Both my training partner and I punctured other tires rather quickly, or tore knobs right down to the casing. However we were unsuccessful when it came to the Mountain King- it held air. At 170lbs (vs my partner’s 146 lbs), I had a better chance at tearing a tire. After several rides, no knobs were torn or were there any signs of cuts in the casing. I inspected the tire thoroughly. The same was true for the Race King 2.2. UST tire that I ran on my rear wheel: no visible damage. This was amazing considering that I sliced the right-front tire of my SUV on a piece of a’a lying on the side of the county road that is above the MTB course. It is also worth noting that the seal remained tight and no burping occurred, I ran 32 PSI in the front (MK 2.4 UST) and 35 psi in the rear (RK 2..2 UST).

On traction, as I had noted in my previous experience in Moab and New Mexico, the Continentals excelled in this type of dusty rocky terrain. The tire offered a cushy ride- I did not measure it rolling efficiency but it does feel a tad slower than say a Racing Ralph or it sibling the Race King, but that is to be expected.

Juan Pablo



Anonymous said...

So how did the race go?

Juan Pablo said...

Dropped 18 minutes from my last performance there ... so VERY good.

My tires/suspension setup floated deliciously through the harsh rocky terrain ... I enjoyed every minute of the downhill! (enjoyed the climb too but that is a different type of joy, as we all know) and had the peaceful grin of confidence that solid tire choice bestows; I knew they would not desert me, that is priceless on a race as grueling as the Xterra Worlds.

The tires were mounted on MAVIC's Crossmax SL