The Olympic venue here in Russia has been downright tropical lately, so it takes a real mental adjustment for me to make sense of Jeff Tumbleson’s testing reports from the Birkie trail. But Jeff has been providing enough information, and a small touch of the fever has permeated my Olympic mindset, so I’ll hazard some initial guesses and recommendations.
Jeff’s reports have all focused on a deep, and deeply refrigerated snowpack. It’s been a cold and snowy winter in the Hayward area. The great lakes are nearly entirely frozen-over for the first time since 1994, and “polar vortex” is now part of the national vernacular. All of this means that we’ve got great information on cold waxes, but it also means that the depth and refrigeration in the snowpack should steer our expectations toward the colder side of the spectrum. Jeff’s report from yesterday highlights this fact, as a snow-temp of -11.4C was instantly lowered to -14C with a pass of the groomer.
Extreme cold is facing a bit of a challenge this week though, as Tuesday through Thursday are forecast to have six or seven hours of above freezing temps. However, given the depth and cold in the snowpack, and the introduction of up to a foot of new snow this week, we’re expecting minimal levels of transformation, and minimal warming of the snowpack. By about 6PM on Thursday we’ll see the end of above-freezing temps, and Friday night promises low temps in the single digits, setting us up for a classic, typical Birkie day.
As of now we’re confident in a paraffin recommendation of Vauhti LF Green as a hardening base under Vauhti HF Blue. Jeff likes to mix a bit graphite into the LF Green underlayer – he uses Ski*Go LF Graphite. We’re still discussing this recommendation, but my feeling is that it depends on a certain level of transformation in the snowpack, and the introduction of some older snow with aggressive grooming. If the race day track surface is characterized by recent new snowfall, then I don’t recommend a graphite underlayer unless you’ve got testing data to support it.
The real question comes as we look toward the fluoro powder and top coats. As always, fluoro powder becomes the critical element in a marathon waxjob. Even in cold conditions, fluoro powders ensure durability as much as they ensure high performance, and getting the right fluoro is critical. Many of the European marathon teams choose not to use liquids or blocks on top of their powders because they don’t feel the durability supports it. I believe that a good top-coat can still provide significant benefit, but I do recognize the importance of the powder layer.
There’s no way to make a good powder call right now for Saturday. We’ll need to continue to test and keep an eye on conditions and the forecast. For this reason, we’ve introduced a new option on our e-commerce site to allow you to choose three different powders to buy as a kit, with 10g of each repackaged in film canisters. This allows us to identify good candidates for powder and get them in your hand so that you retain control of your circumstances. Here’s a link to the sample kit.
And here’s a run-down of our powder recommendations:
hfC21.1 – this is Vauhti’s newest cold powder, tested over the past year on the World Cup as C152. In our testing and in Jeff’s testing it has been really even with the normal hfC21. Both powders run quite cold – all the way down to -20C. Jeff has had good luck with these powders in his testing, and has repeatedly picked them in the very cold weather he’s seen.
330C – This was our best race powder last season at the Birkie, and it remains my personal favorite for the second half of the race, or any scenario that includes slightly milder than anticipated temps, including later starters. This is a World Cup powder for new cold and dry snow that gets lots of early season action in Scandinavia, and has been good for us in temps down to about -15C and up near freezing after a cold night.
C11 – In the event that the mid-week warming trend is stronger than we anticipate, or has a greater effect than we’re expecting, resulting in a significant level of transformation in the race-trail surface conditions, this is a great choice. C11 runs in a very similar temperature range to the 330C but is better in older snow that has seen either some freeze-thaw transformation, or a lot of grooming.
hfC15 – Jeff is pretty certain that hfC15 is too warm for the snowpack that is already on the ground. The only reason that hfC15 could come into play would be if the storm system that is a potential for Thursday gets pushed back a day, and we end up looking at mild temps and new snow on Friday night. Now that would make for an interesting situation!
OK – that’s four powders, not three. But I’m guessing that most of you have a better idea of how all of this will go than I do, sitting in my hotel room in Rosa Khutor!
Powder Application
We recommend ironing all of these powders at 180 degrees C. Vauhti has done a lot of testing, and they favor a high iron temp and a rapid application. These powders flow and spread easily at 180 degrees, and they’re not hard to work with. Please use a suitable respirator and a well ventilated space. Vauhti recommend roto-corking or hand-corking the powder after it has cooled. We like using our Red Creek high-friction hand cork and a little bit of elbow grease.
Top Coats
Top-coats are always pretty specific to race-morning conditions. However, my best guess is that the hfC21 block will make better feeling skis. This is especially true if we’re pushing the 330C powder toward the cold end of its range, and we want a little colder-running surface for the first half of the race. In the event that the conditions are more transformed, and acting quite cold, the hfC21 liquid is a good bet. Jeff has had surprisingly good test results in very cold conditions and older snow. My feeling is that this would require a surprising amount of transformation of the snowpack, so I’m not betting on it.
My Bet
If I had to wax my skis right now I would plan on an overall cold, new snow scenario, but not a frigid one. I would go with:
LF Green
HF Blue
330C ironed at 180C and hand corked
hfC21 block hand corked aggressively (you can hand-cork the powder as well).
Jeff’s Bet
LF Green/LF Graphite
HF Blue
hfC21.1
hfC21 block