OK – it’s past time to finalize a Birkie recommendation, with apologies for being a bit late. We’ve just finished the pre-race team meeting for the pursuit races here in Falun, and for those events we’ll make the final call about 45 minutes before the start of the race. We don’t have that luxury for the Birkie, so we’re forced to stick our necks out and make some predictions. Here’s what we’re saying:
Vauhti LF green race paraffin
hfC21.1 fluoro powder
hfC21.1 fluoro block
We’re leaning really heavily on Jeff Tumbleson’s experience skiing race waxes on the Birkie trail several days a week, all winter long. Testing for marathons is incredibly difficult because the time-frame makes it hard, and the course covers a tremendous amount of terrain. This year the extreme cold in the lead-up has provided very few testing opportunities that are really representative of race day. So local experience with conditions and products is key. That’s why Jeff gets the big bucks. That, and the fact that he’s the implied plural in the “we”, and the only one on-site to get mad at if it all goes wrong.
Based on current conditions and the forecast it looks as though the temps have come up from rock bottom, and the overnight will be in the warm side compared with recent days. Race morning looks more “average” than “bitter cold”, at least according to the thermometer. With starting temps forecast for the high single digits and finishing temps in the teens, we might expect not to be on the very coldest waxes.
However, most of the circulating recommendations are for extremely hardened bases and an overall very cold approach. In part, this may be a caution in acknowledgment of the danger of going too warm in the wax. That’s not what you want. And it may be influenced by everybody’s testing all week long with low daily temps down well below zero.
Recent snowfall is another consideration. The forecast looks good for snow continuing into race time. This would have the effect of minimizing the “refrigeration” effect of a freshly groomed extremely cold snowpack (since the surface is likely to be freshly fallen snow of a more moderate temperature). But today’s testing strongly underscored the importance of a hard race paraffin in the build-up. HF blue was not as good as LF green, or other greens from other companies in Jeff’s testing today. Given the very wide range of the LF green, and it’s ability to carry into quite moderate temperatures, that is a very safe call. If LF green is testing well today in fall snow, then it is extremely likely to be testing well tomorrow in a continuation of the snow event, even if temperatures have moderated five or ten degrees. We don’t currently have strong testing evidence that a hardener is helping in the new snow. So even though we were really getting behind the idea earlier, I don’t think we need to emphasize the hardener at this point. I would be inclined to skip the 30F. But having said that, it’s unlikely to hurt.
Why is Vauhti LF green so good? I asked Aki Karvonen today here in Falun. He said it was “lotto”. It took a while to parse the Finglish, but we figured out that he was basically saying he won the lottery on that one. But he also explained that it’s easy to go too hard with paraffins, and that they had tested a whole bunch of formulations that were considerably harder than LF green. The harder paraffins had easier static release in bitter cold at very slow speeds and low loads, but the LF Green formula was a real sweet spot in the hardness spectrum, providing great running speed once you get moving and at higher loads, and the fluoro additive content seems to have been just right as well.
For powders, I’m not quite as confident in absolute terms. But I also feel that we’re looking at very strong options with relatively little downside. All week the hfC21.1 powder has been the best, and Jeff is pretty sure that’s the right call for tomorrow. However, the LDR powder hasn’t been far off the mark, and I have a personal hunch that it could provide a good second-half advantage. I’m also really confident that the 330C could provide excellent results (that was our winner in Craftsbury on falling snow in the single digits a couple of weeks ago, and has been our Birkie wax for the past two seasons). But – hunches aside, I think the sensible call is the best wax from testing. And so we’ll say hfC21.1 for the powder.
The topcoat call is easy. The 21.1 block has been really good for Jeff in testing, and that’s what we’ll stick with.
For people who have bought our Birkie kit, you’ve got some LDR powder, and you’ve got 21.1 block. Your options are to iron the 21.1 block, or iron the LDR powder. If you want to iron the block, I recommend the following procedure:
- Rub the block onto the base (after scraping and completely brushing the paraffin).
- Hand cork the application.
- Rub MORE block onto the base.
- With the iron set to its highest setting, hold a sheet of fiberlene between the iron and the base, and make a long, slow (about 20 seconds) pass from tip to tail. If the finish doesn’t look right, you can make a second pass, or go back and touch-up spots.
- Let the ski cool completely, and then just brush it out.
- Rub the block on once again, and hand cork vigorously. Let it set for ten or fifteen minutes, and brush.
If you’re starting in a later wave, or you want to take a chance on a second-half advantage, you could run with the LDR powder with the 21.1 block on top.
Good luck. If it all goes terribly, don’t look at me. I was in Falun!
Zach