Garmont (Radium) Backcountry Skiing Boots — Parker’s Beta

Post by blogger | September 2, 2009      

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Hi all, Paul Parker of Garmont here.

Thanks for your interest in the Radium here at Your feedback is important and we listen, so I’ve been tracking the discussion here about Radium shell sizing. To help, I’d like to clarify some of the questions that have been raised and explain a bit about how our ski boot development process works.

Sole length/size: Ski boots are developed from the inside out, rather than the outside in. We don’t develop a boot to a specific sole footprint or sole length, we develop it from the internal mold, which along with other elements that I’ll explain below, then determine the sole length.

It’s not uncommon for alpine skiers to refer to their sole length as the boot size, probably because it’s stamped on the side of the boot for easy binding adjustment. Certainly a bigger boot in the same model will have a longer sole length, but sole length does NOT indicate the size. It’s the inner mold, the “forma”, that determines the size. That is what some call the last, although it’s not truly a last since leather or fabric isn’t lasted around its form. It is as close to a last as an injected plastic shell gets, it’s the heart of the boot and determines overall fit and size according to the MPS (Mondo Point System). (For a comparative view of how all this interrelates, please see the Garmont boot size and sole length chart at the end of this post.)

Each new Garmont backcountry skiing boot model uses a new series of molds, including the forma. It’s in that boot’s development that we use market feedback on existing models, as well as the intended use for this new model, to determine how we should build the forma and resultant fit for the new boot.

It is normal to have a significant difference in sole length between two different models (same size) from the same manufacturer. Several critical elements result in this variance in length, one of which is the “forma.” Its length is determined by the Mondo Point measurement inside the liner. The forma may be a bit shorter and still produce the same size of boot if the liner is designed to be thinner, as in a race boot. This can result in a few millimeters of difference in sole length for the same size boot.

Two other significant elements that determine sole length are shell thickness and toe shape. Regarding shell thickness, it’s not uncommon for a beefy boot to be several millimeters thicker at the toe and heel than a lightweight AT boot. Since it’s the internal length that determines the size, and should be very similar between boots, then the thicker-walled boot shell is going to be a lot longer on the outside. We reinforce our performance boots like the Radium significantly in those regions that are subject to the torque of the binding, so that can also add some length.

Another important element that determines sole length is the fact that, whatever our boot design and shell thickness, we must respect the ISO norm for ski binding compatibility. There is a required amount of “free space” at the toe to accommodate the binding wings or binding toe, so whether or not the boot toe is shaped round or square or somewhere in-between can determine significant differences in the length we have to make the lip of the boot sole to provide free space for the binding.
Add up all of these elements and you get the sole length. It’s from the inside out, the result of the Mondo Point internal measurement including the liner, thick or thin, the boot toe shape and sole that respects the ISO norm, and the shell thickness. These are all elements that vary widely between different boot designs and models, and will result in varying sole lengths.

This is why good backcountry skiing bindings should be easily adjustable. I understand too well that it can be pain to adjust any binding when the snow is calling, as I’ve often had to test different boots on the same pair of skis on the same day and had to adjust then each time that I switch. Still, as Lou mentioned in the comments on the previous Radium review, adjusting your binding shouldn’t pose undue wear in its mechanism any more than stepping into a binding does. Of course a Dynafit®-type binding has less workable range than a step-in and must be adjusted more precisely, but it’s not going to hurt the binding.

Shell volume: A boot’s closure should be effective in adapting a boot’s volume to satisfy big differences in foot volume. Northern European feet tend to be wider and higher volume, Southern European feet narrower, narrower heel, and lower volume, American feet wider in the forefoot, medium to low volume, narrower heel. The adaptability of the design to different feet is one of the most important reasons why we developed the Radium’s overlap design. Its overlap wraps around the foot, rather than smashing down on it from the top, to reduce the volume. This is an important reason why most of the best alpine boots are overlap. We have found in practice that the Radium does successfully fit a wide variety of feet. There are other things besides the shell design that will help you satisfy the extremes in foot volume, and how you choose your fit, i.e. sizing up or down. Footbeds, in particular, and their thickness, can make a huge difference in matching the foot’s volume to the shell. If you have low-volume feet, you probably know how well a custom footbed of the proper thickness can improve any boot’s fit for backcountry skiing or otherwise.

Narrow toe: Toe caps should always be used when thermoforming Radiums, or any thermoformable boot’s liner. If you are on the fence between two shell sizes, and should you pick the smaller one, you need to really pad your toes when thermoforming the liners. It’s uncomfortable during the thermoforming process but results in a better fit for backcountry skiing because the padding and your toes push out more space for your digits. Custom boot fitters are especially adept at this process and tend to size shells down quite a lot. Non-thermoformed liners/boots should feel tight all over, and will feel particularly tight at the toes. If your boots are comfortable enough to ski in without thermoforming, chances are they are too big. This is an important thing to keep in mind while shopping, as it’s tempting to choose boots by how comfortable they are when you try them off-the-shelf, rather than how they feel after liner molding and such.

How the manufacturer manages shell sizes: This is something very important to know when fitting a pair of boots for backcountry skiing as covered here on, and especially important when switching between brands. Different manufacturers choose different shell “breaks”, i.e. whether they bump up the shell size on the half or whole size. In other words, some manufacturers 27.5 comes out of a 27.5 shell (Garmont’s boots are designed this way), while others’ come out of a 28.0 shell with a thicker liner. The 27.5 that comes out of a 27.5 shell will always produce a closer fit for the same foot than a 27.5 that comes out of a 28.0 shell.

Since Garmont shells break on the full size, a 27.0 and 27.5 come out of the same 27.5 shell. Many of our competitors have chosen to build the 27.5 and 28.0 out of a larger 28.0 shell. Not only will those two 27.5s from different manufacturers fit much differently, but they will have different sole lengths.

These different elements in boot design result in different fit and the sole lengths discussed. I hope this information has been of some help to the readership. Thanks again to all of you for your interest in Radiums. Personally, the Radium is my all-time favorite boot.

( guest blogger Paul Parker has been involved in the backcountry skiing equipment industry since the dawn of creation. On about the second day, he was instrumental in Chouinard Equipment’s entry into the arena, and has also worked with Tua, Scarpa, G3 and numerous other companies. He’s presently with Garmont and works hard making sure their boots are state-of-art. Parker is also an author, his most well known work being the well regarded how-to book Free Heel Skiing.)

Garmont backcountry skiing boot size and sole length chart.

Garmont backcountry skiing boot size and sole length chart.

Shop for Garmont ski boots here.


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68 Responses to “Garmont (Radium) Backcountry Skiing Boots — Parker’s Beta”

  1. Wayne Nicholson September 2nd, 2009 8:41 am

    Thanks for all the information on ski boots, normally very hard to find. I keep breaking my big toe nail every year jumping from cliffs with my boots, this info will help make a better choice next time i hop.

  2. Tom Gos September 2nd, 2009 9:48 am

    Thanks for the info. I have one suggestion for you. I find that I have to go up one shell size from my alpine boots to my AT boots in order to prevent smashing my toes (and losing toe nails) while skinning in tour mode. I know other people make the same choice as well. The down side is that I end up with a higher volume shell when all I really need is more inside length. This is particularly problematic with my low volume feet and as a result I can’t get the same sort of downhill performance in a touring boot that I expect out of an alpine boot. So my suggestion for future AT boot is to simply add 3 to 5 mm to the interior length of a given size without changing the rest of the shell volume. It seems that many AT manufacturers are going to ever wider interior width at the ball of foot in order to improve “comfort” but I think that a little extra interior length would be a better design and won’t compromise downhill performance as much. Just my 2 cents.

  3. NickD September 2nd, 2009 10:40 am

    Thanks much for the informative post. I have, however, always felt that Dynafits “loosen up” over time. The evidence is qualitative – mostly the feel of binding/ski combo – and I attributed it to wear in parts under a lot of stress (e.g. the pins that connect the heelpiece to the boot). But it seemed to get worse once I started going back and forth between my Megarides and Radiums last season. But it could be that it’s due to variances in re-setting the gap (which I do by eye when I’m in a hurry) and not the screw adjustment.
    So I’m going to try and isolate the issue by setting up an old pair of Dynafits on a jig with an electric screwdriver and track the tolerances as I adjust the bindings a few hundred times. Nothing like a little independent data – I’ll report back.

  4. Lou September 2nd, 2009 2:31 pm

    Nick, the other thing that wears is the ski topskin under the heel unit, since when you’re weighting the heel unit you are supported by the ski topskin under the heel pedestal. I’ve seen some very severe wear of ski topskins in this area, with high use bindings. Once the ski topskin has much of a divot or wear area in it, the heel unit will have play. Lot’s of for/aft adjustment could possibly cause this as well, if the top skin is of the less durable type, but it’s mainly just aging and heavy use that does it. Also dependent on how heavy the person is, and how much grit/dirt they get in to that part of the binding.

  5. NickD September 2nd, 2009 3:49 pm

    Lou – good point – I hadn’t thought about the ski itself. I have experienced the metal insert in the heel (held in by a philips screw) loosening up, too.
    I should put this all in context – I am obsessed with tiny rattles and vibrations in cars, gear, etc., so I probably notice things others might not. I tend to feel the small Dynafit movements when I’m riding up a lift and the binding/ski are hanging free. Those little movements haven’t translated into the kind of noticable performance issues that I’ve seen in other rigs (e.g. the vertical chatter/movement that Freerides seem to develop as they wear).
    I have broken a Dynafit heelpiece by snapping the column – but that was due to not noticing ice buildup on a slushy day and trying to force my heel to lock.

  6. Lou September 2nd, 2009 4:38 pm

    If you’re riding a lift with Dynafits, you might want to re-evaluate your testing procedures :angel:

  7. Lou September 2nd, 2009 5:09 pm

    I just added the 2009/2010 Garmont sizing and sole length chart to the end of this post.

  8. Mark September 2nd, 2009 10:41 pm

    I lost one Dynafit screw-in boot heel fitting and was forced to make some strange tele-like turns with one ski that day. As to shell lengths, I may get Radiums, but even the same shell size as my current MegaLites is 5 millimeters longer. Due to nearly unbearable tightness of fit in the MegaLites, I will consider the next shell size–a full 15 mm longer so I’d have to remount my bindings.

  9. Verbier61 September 3rd, 2009 1:00 am

    really useful, thanks! I’ve been using megarides for many years, and was stoked when the radiums were released. However, when I finally tried radiums in the shop my heels (perfectly locked in megarides), danced too much in radiums. Is there anything one can do to it?

  10. Peter September 3rd, 2009 8:25 am

    Kudos to Paul’s ‘boot sizing 101’ comments above, even though most of that information is common knowledge to any gearhead. I wonder how aware Garmont is of the fit-issues reputation the Radium has garnered? It’s quite common for me to meet a Radium owner who says (or for me to know a Radium owner who posts on’s forum) something along the lines of: ” tight in the toe box, big in the ankle, medium in the heel. It wasn’t shaped for my foot at all. The Endorphin fit much better to my foot: medium-to-wide in the toe box, but low volume overall, and tight at the heel.” It’s quite common for Radium owners to have to have the shell punched out laterally in the toebox area; sizing up is sometimes done as a last resort, but then the sloppy heel/ankle issue is exacerbated. I’m referring here to what might be considered ‘average N american’ type of feet. Thx for any comments, Paul.

  11. Paul Parker September 3rd, 2009 8:28 am

    Hi, Paul P. here again. I have a bit of info that might help the last couple of questions. Mark, be sure to try Radiums on before you size up from your tight Mega Lites. Certainly you may need a bigger size, but you might find that the more anatomical last of the Radium has enough room. If they are too short it is more likekly that you need to size up, but general tightness around your foot can be remedied with thermoforming, if it’s not too extreme.
    And regarding Verbier61’s experience with heel lift in the store: the Radium shell’s heel is actually a bit narrower than the Mega Ride. When you try them on before thermforming, you foot can get pushed forward because it has not yet made the heel pocket that you get with the thermoforming. Because your heel is pushed forward it may feel sloppy. That sensation goes away with themoforming because your foot moves back in the liner/. This is another important reason to use toe caps when thermoforming: they not only increase toe room, but they push your foot back to form the heel pocket. With properly cooked liners, your heels should feel more locked in than your Mega Rides. Cheers–Paul

  12. Paul Parker September 3rd, 2009 8:45 am

    Peter, good comments. We are aware of these points, which in large part can be remedied. One is to be sure–sorry to repeat myself–that you use toe caps when thermoforming. This season’s Radium liner has been improved with a thinner, softer toe section that helps the space issue, as we know a lot of people aren’t using toe caps. Even with this newest liner, be sure that you use them.
    And very important, buckle the lower CUFF buckle tightly, with a bit more effort than your normal buckling procedure.The lower shell of the Radium is very stiff Pebax, and with its high overlap design it is very important that this coff buckle closes properly. It’s the most important buckle on the boot because, unlike a traditional alpine boot, the lower cuff buckle is in the middle of the overlap and does more to close the boot than any of the other buckles. Paul

  13. harpo September 3rd, 2009 9:01 am

    Tom, you should also consider that there is much a competent bootfitter can do to give you more length at the toe in addition to toe caps: heel lift wedges, compressing the liner after molding, blowing the shell in front of the big toe. Make sure you find bootfitter experienced with AT boots if doing the latter, as they have thinner shell material with different thermodynamic charateristics than alpine shells, and you also need to take care that the result will fit into the bindings you use, though the latter is a concern more for non dynafit AT bindings. I have two freinds who are bootfitters in my town and would do the work for cheap but I go to the guru an hour away and pay full price for blowing work on AT shells.

  14. Lou September 3rd, 2009 9:44 am

    I thank Paul so much for helping us out here! Sure, some folks know much of the general info, but nothing wrong with repeating it with focus on a given product.

  15. SB September 3rd, 2009 10:07 am


    I have a couple of questions about the Radium.

    1) Do the half sizes (with same shell size such as 26 and 26.5) also have identical liners?

    2) How do the women’s Radium’s differ from the men’s or are they the same other than the size range?

    Also, my boot fitter, in addition to a toe cap, used a toe spacer like those that women use to paint their toe nails next to the big toe and the little toe. My fit turned out great with good toe space.

  16. Marcus September 3rd, 2009 11:45 am


    I’ve heard that the new Prophet boot (Telemark) is basically the same fit as the Radium. Would the same fitting and thermofitting procedures apply to this boot?

    Thanks for the great article.

  17. Karl September 3rd, 2009 1:41 pm

    I think Peter (above) is quoting something I wrote on the TGR forum — I wound up buying Axons, which seem to fit identical to the Endorphin.

    The comment I made about the fit of the Radium vs. Endorphin was made based on shell fit: moving my bare foot around inside a 27.5 shell in both boots, it was clear that the Endorphin’s shape simply fit my foot better than the Radium. While thermoliners can accommodate some of the differences between people’s feet, I think most bootfitters would agree that it’s best to start with a shell that’s as close as possible to the shape of your foot — and then fine tune the fit from there (thermoliner, punch, grind, etc.).

  18. Paul Parker September 3rd, 2009 6:06 pm

    Regarding questions form SB and Marcus, first SB’s:
    1) The half sizes are differentiated by a thicker footbed in the same liner. If you use your own footbed, which I recommend, you shouldn’t find a significant difference in 26.0 and 26.5.
    2) Women’s Radiums, and the new Women’s Luster that is available this fall, have a women’s-specific liner.

    And Marcus:
    We started with the Radium last for the Prophet NTN, but made some changes from the ball of the foot forward to accommodate the flex in a telemark. So the Prophet NTN is more or less the same as a Radium behind the metatarsals, and is roomer from the metatarsals forward to accommodate the foot’s lengthening when it flexes in a tele..
    There are couple of other details that vary the fit between these two boot models. One is stiffness. The Radium shell is much stiffer than the Prophet NTN, which of course has to have sole flex. A fact about shell stiffness is that even if two boots are from the same mold, the stiffer one will always feel tighter because the plastic has less “give”.
    The other detail is the overlap. The Prophet overlap starts farther back on the lower shell to make room for the bellows. This changes the feel of the fit when the buckles are cranked.
    All of that said, everyone who’s tested the Prophet and also has experience with the Radium has chosen the same size as the Radium. I think the Prophet is one of the best-fitting boots I’ve ever had on my feet.

  19. Paul Parker September 3rd, 2009 6:08 pm

    P.S. to Marcus–The thermoforming process should be the same.

  20. NickD September 3rd, 2009 6:15 pm

    @Lou Dynafits/AT skis are de rigeur here in Telluride in and near bounds. Between Palmyra, Gold Hill chutes and Bear Creek, they’re much kinder on old legs than hauling around an alpine rig. :happy:

  21. Lou September 3rd, 2009 6:35 pm

    I thought all you Telluride guys were tele whackers :cwy:

  22. JW September 3rd, 2009 9:32 pm

    just adding my $.02:

    “Tom Gos September 2nd, 2009 9:48 am
    I find that I have to go up one shell size from my alpine boots to my AT boots in order to prevent smashing my toes (and losing toe nails) while skinning in tour mode. I know other people make the same choice as well. ”

    I’ve had a similar experience. Not with the Radiums, which I have yet to pull the trigger on, but with a predecessor Garmont–a great boot for my flat C width feet, just short, too short, and a long tour on them cost me both big toe nails. I used the same shell size as my alpine boots, and had the Garmonts fit by a very knowlegeable BC shop at the base of Teton Pass. Toes caps, spacers, everything. Just too short. I have to try the next half size up, which takes me to the next full shell size, and possibly a worse all-around fit. I note that Louie D. also said he sized up when he went to the Radiums from another boot.

    I’m not convinced its a boot fitting issue, as I had a great fitting. I suspect a liner issue, and others have posted a tgr that they had better results with an aftermarket liner. and so was happy to hear Paul say that there was a change to the Radium liners for this year. For me, that means avoid the 09 models and pay more for the ’10s; I may get a friendlier liner fit.

    thank you paul,

  23. Verbier61 September 4th, 2009 1:03 am

    very, very useful insight on how termoforming can change the fit, thanks!
    I suggest you to disseminate as much as possible this info, because otherwise I’m afraid some old megaride/endorphine/etc users will leave the radiums in the shop

  24. Lou September 4th, 2009 7:54 am

    Good points you guys. I’d add that unless you’re in denial with a nice $$$ new pair of boots (which I’ve been guilty of myself), you should be able to easily feel if they’re too short after molding. Personally, I’ve found I frequently get my best fit by keeping to the smaller side of my shell choices, and punching out the shell toe just slightly for my big toe. If I upsize the shell, I have trouble fitting my heels, though if enough work is done I can usually fit anything.

    Parker didn’t get specific about this, but my impression is that the Radium shell toe box is a bit smaller in volume than some other boots, and may thus require the user to be in a longer shell, which moves the toes a bit farther back into the larger part of the toe box. In the case of Louie and I, the Radiums we have seem to be the best shell fit, and we easily have a three-finger fit without liner. As Louie mentioned in his review, the end result of all this is Radiums tend to be a longer boot for a given foot, as compared to other models/brands. For us, we’re in the 325 mm Radium shell (see chart above). The next shell size down is 315 (a centimeter shorter), which felt too tight in the toe for us but would probably have worked with some toe punching.

    In comparison, I use a 306 mm length shell in my Dynafit Zzeros, with toe punched and liner agro molded at the toe. That means my ZZeros are a full 2 centimeters shorter than our Radiums. Not a big deal, but I definitely notice it when swapping back and forth.

    Another thing. You can indeed compress the bejezus out of your liner toes to get space while molding. BUT, at a certain point you are going to have very cold boots because you’ll loose most of the insulation thickness of the thermo molded foam. I know because I do this all the time. If you ski in colder climates or easily get cold feet, using extra compression to get your toe fit isn’t going to cut it and you should just bite the bullet and upsize your shell and liner size, or punch out the boot toe and perhaps use a larger liner.

    Also, at a certain point, when you try and create more space in front of your toes, you’ll end up trying to stretch the liner in length after use up all the compression available. You can get a tiny bit more that way, but not much, in my experience. And stretching the liner in length makes the whole lower liner thinner and may screw up the fit over other parts of your foot.

    Another thing about the Garmont Radium. Since they indeed appear to have some extra room in the shell for a given fit, they would logically be warmer. Experience bears this out. Nice toasty feet in a beefy performance boot, Garmont Radium!

  25. ian cruickshank September 4th, 2009 12:09 pm

    Nordica Doberman 130 size 7, shell 295
    Garmont Megaride size 26, shell 300
    Garmont Endorphin and Axon size 26, shell 297
    Garmont Radium size 25, shell 295

    Skied them all over the last several years. Only the Radium needed custom work
    but now it skis great, despite a one-finger fit. My only concern would be kicking
    uphill steps for a long way.

  26. Bar Barrique September 7th, 2009 9:00 pm

    I plan to try these on, and, I especially like the one position forward lean (although the Holy Grail would be a user adjustable one). If they can work with some minor custom work; I might opt for them. It is just that the Megarides fit so nice, even before the liners were molded.


  27. Jed Porter September 21st, 2009 2:09 pm

    How about some commentary/review of the Garmont Helium. Radium’s certainly ski stiffer, and seemed to promise better touring than Megarides. How do Helium’s stack up? Will we even see Helium’s in US shops? Or is everyone going bigger and bigger? Going a step further, how ’bout a full comparison of Tech compatible overlap boots: Methods and Factors and Heliums and Radiums and ?… I’m totally content with Parker/Garmont’s perspective on this, no need to burden the Wildsnow machine with further objective testing if I’m out in the minority here…

  28. Lou September 21st, 2009 2:18 pm

    Jed, we have our boot overviews coming for this season. And I’ll make an effort to look at the Helium. Thanks for asking. ‘best, Lou

  29. Grover Meyrose October 5th, 2009 6:49 pm

    You speak of using a “toe cap” when thermoforming Garmont Radium’s. I have just ordered a pair and would like to know what a “toe cap” is and whether its something I make myself.


  30. Mark October 5th, 2009 7:24 pm

    Cut off the toes from a pair of wool socks–toe caps. Shops sometimes have commercially made ones, but it is easy to make your own.

  31. Lou October 5th, 2009 8:23 pm

    If you use sock ends, sometimes you have to use two to get enough thickness. That’s actually what I use most of the time. Before molding I also wad up some duct tape on the ends of my longer toes to make sure I don’t get toe-bang.

  32. Grover Meyrose October 5th, 2009 9:26 pm

    Thanks for the tips on boot fitting. With the cost of boots these days, getting it right the first time is critical!

  33. Lou October 6th, 2009 7:08 am

    Grover, only, you can mold most liners a number of times! What one needs to get right the first time is the initial fit, which a lot of shoppers mess up because they try to figure out which boot is correct by trying on with unmolded liners.

  34. Bar Barrique October 26th, 2009 1:42 pm

    I ended up buy the Radiums. The fit before they were molded was not the best, but when I did a shell check, the size seemed very close to my Megarides. After molding the liners I am happy with the fit. One thing I might try next time I go boot shopping is to take the liners, and, foot beds from my old boots. This can tell you a lot about the potential fit. I did this when I got home, and, I was able to detect some slight differences in fit between the two boots

  35. Dustin November 18th, 2009 10:32 am

    Hi I was curious if anyone could expand on the Cuff Alignment Adjustment. I’ve bought a pair of Radiums and they wheren’t set up just right when I was fitted. The adjustment looks simple enough but I’m not having any success.

    Thanks for any help.

  36. George November 18th, 2009 2:30 pm


    Looking forward to a review of the Garmont Helium.

  37. Olive December 9th, 2009 7:27 am

    Hi Paul,

    One quick question regarding the Radium liner. I have noticed to different type of liners in the Radium both Gfit but look different. I would like to know if it is just a change in the look or if there are some substantial difference between the 2008/2009 Gfit liner and the 2009/2010 Gfit liner ? I’ve seen that both are done by Palau. I’ve tried both and it seems that they are some differences but it was not in the same shop (so may be one shop has the 2008/2009 model and the other one the 2009/2010 model).
    Could you also explain us if they are other differences between the 2 models( 2008 and 2009 model). I’ve also heard that the skiing position is now 25° instead of 23° (which is a good news for me !)


  38. Dan December 10th, 2009 12:14 am

    Re: Thermo fitting Radium Liners:

    I am aware of Lou’s opinion regarding heating liners to check the fit for new boots before purchasing the boots. FYI: This is not the opinion of the shops that I have talked to here in western Washington recently. I queried several shops in the Bellingham to Seattle area about heating Radium liners when checking out the fit. They all flat out refused to heat the liner unless one has made the decision to purchase the Radiums. I was told by two shops that Garmont claims the Radium liners can only be heated 3 times. One “boot fitter” even went so far as to tell me that he wouldn’t want a pair of liners that had been heated previously for someone else’s foot.

    BTW: I was fed a similar line about Dynafit and Intuition liners. However, last March, I was fitted for new liners at Intuition in Vancouver, B.C. They heated 3 different sets of liners for me until we found the best fit.

    Paul, if you are reading this, what is Garmont’s recommendation to retail shops regarding heating of liners?

  39. Olive December 11th, 2009 5:15 am

    I’m looking for a pair of Radium but still have some doubts regarding the size. I spent 1 hour trying the boots yesterday evening but I’m still not convinced. May be you can help me ?
    I currently use a pair of Scarpa Spirit 3 in 27. I’ve tried the Radium in 27 and 27.5 and I cannot decide what is the best for me. I am oriented on the 27.5 because I need extra space for my toes but I don’t want to move in the boot in the future. I have seen that the shell is the same for 27 and 27.5 some may be it is not a big deal, only a difference of liner if I’m right ?
    Last but not least, regarding the heating of the liner, is it something specific to Gfit liner or is it possible to heat them with any machine for thermofitting ?
    Thanks in advance

  40. Paul Parker December 11th, 2009 2:53 pm

    Hi folks,
    Sorry that I didn’t get to your questions sooner. I haven’t been on the blog for some time. Thanks for your interest in Radiums.
    Dustin: to adjust the cuff alignment: loosen the center bolt with a 4mm hex. Rotate the outer ring using something sharp-ish that fits into the ring’s indent. When the indent is on the bottom, the cuff is alighted to its outward maximum, the most common position. When the indent is at the top, it is tipped to the inside to its minimum. Choose your position and tighten the center bolt securely.
    Olive, re: liners, this season we added a thinner, softer, stretch toe cap to the Radium liner, which is probably the difference that you see. It makes the toe area a bit easier to thermoform. We also simplified the cuff area a bit to standardize our liner models. There isn’t any performance difference in the 2008 and 2009 liners. Regarding forward lean, to get the most out of the shell, be sure that the lower cuff buckle, the second buckle down, is buckled tightly. This positions the overlap against your lower leg to get the most forward lean.
    Dan, regarding thermoforming, we say three times but that isn’t a hard and fast rule. You can cook the liners up to 6 times as long as you do it properly with a convection oven and don’t burn them. Regarding cooking before buying, it’s the dealer’s call and we can only give advice here. That said, my advice is that if you really aren’t sure, cooking first is a good idea. It won’t hurt the liner and will certainly make you feel better about your purchase.

    Olive also asked about sizing: Scarpa’s and Garmont’s shell sizes break differently. All bootmakers build shells in full sizes and use a thicker footbed or liner in the in-between sizes. Scarpa’s 26.5 and 27.0 are out of the same mold, while our 27.0 and 27.5 are out of the same mold, as you’ve observed. You are right, there isn’t as much difference in a 27.0 and 27.5 because the shells are the same. Comparing your Spirits and Radiums, because of the shell break, if you were to choose a 27.0 Radium it would be approximately 5mm longer than your 27.0 Spirits.
    I hope this is helpful.

  41. Geoff January 7th, 2010 11:40 am

    Hi all,

    after spending 4 frustrating hours trying on boots today and getting very contradictory info from 2 salesmen (including “shell fit doesn’t tell you a single thing about a boot”!), I am turning to the collective wisdom of Wildsnow for help.

    My situation: I am looking for a “beefier” boot to complement my Scarpa Lasers, but need something warm as I have had bad frostbite in the past. I have six toes (not figuratively, I actually have 6 on each foot), but otherwise a narrow heel.

    My questions:

    – Radiums fit me, but I only get enough width with the 27.0 shell, which has 25 mm of space in the “shell test”. Even though the fit is snug with the liner, will this be way too big after the liner is cooked and packs out?

    – Spirit 4s fit well at 26.5 and 27.0, but my big toe touches the front slightly. I was told that punching it out even a little would ruin the shell, but I recall reading here that this should be possible?

    – Both the Spirits and the Radiums were shown with non-thermoformable liners (eg., Padlock from Garmont), and when asked I was told that “no one likes the real thermoformables,” and therefore they only offer them on demand. Does anyone really agree with this?

    Sorry for such a long post, but if anyone can make any suggestions the beer’s on me next time you’re in SW Germany.


  42. Mark Worley January 7th, 2010 4:55 pm

    People do like the real thermoformables, and I’d be pretty surprised if Spirit 4 or Radium normally come with anything else. 25 mm gap from heel to shell is too much, as far as I am concerned. Both are great boots, by the way.

  43. Ed March 21st, 2010 8:46 am

    I know this is an older post but I am looking at the Radium and had some fit questions. I’m switching over from Tele to AT and the boots I’m coming out of are Garmont Syner-G in 28. They are too big for me. I’m a 10.5 street shoe and I have a little wider than normal fore foot , narrow heel, and oh yeah … flat feet.

    I picked up a pair of Garmont Mega-Rides 27.5 (sizing a bit down because of my too big Syner-G 28’s) but they are WAY too small. Too narrow in the fore foot and to small in the toe box. I was thinking of having them punched out but I really don’t think it will cut it. I’m wondering if the Radium might be a little better in terms of a starting point. It looks like it has a little more room than the Mega-Ride so that it might be easier to get a good fit after punching out.

    I’ve used Scarpas before (only Tele) but found that their high arch hump really bothered my feet so I’m hesitant to try them in AT. I also tried on a pair of Black Diamond Factors in a 28 yesterday and found that they fit pretty good. I’m holding off on buying them because I’ve heard as a brand they don’t hold up and typically when I buy a boot and get it to fit I like to run them into the ground before replacing them.

    I’m also thinking about the Dalbello Virus but that’s only assuming I can find a pair in my size and not have to pay full retail for them… doubtful.

    I’m looking for boots that will see 95% BC use and only a little in bounds. I’m willing to trade a little DH stiffness for something that tours and climbs better.

  44. PatS April 30th, 2011 7:44 am


    I own a pair of size 28 Endorphin, which are very comfortable, but a bit loose due to normal packing). Since I’m switching to a dynafit setup, I just got myself a new pair of Radium`s, size 27. They fit quite tight at the toes. What would be your suggestion: try to heat up the shell and liners to get a decent fit on those 27, or go directly to a size 28?


  45. Doug Chatten July 22nd, 2012 5:13 am

    Will the new Garmont COSMOS size 26 have the same BSL as the older ENDORPHIN (silver & red) size 26 which is 297mm?

  46. Paul Parker July 22nd, 2012 5:52 pm

    Hi Doug,
    I don’t have the sole length of a 26.0-26.5 Cosmos at my fingertips but a 27.0-27.5 is 306mm, so a 26 should be @296mm. I’ll double-check tomorrow.
    Paul P.

  47. Paul Parker July 23rd, 2012 7:27 am

    Confirmed 296mm for a Cosmos 26.0-26.5.

  48. Doug Chatten July 25th, 2012 4:34 am

    Thanks Paul. Do you know when they will be available for purchase?

  49. Lou Dawson July 25th, 2012 7:50 am

    This fall.

  50. Paul Parker July 25th, 2012 7:54 am

    I’ll get you a more specific delivery date.

  51. Mile July 25th, 2012 8:52 am

    Hey Paul,
    Can you tell me how much stiffer the G2 in a 110 flex would be than the Radium?
    Perhaps on a percentage basis?

  52. Paul Parker July 25th, 2012 9:33 am

    Hi Mile,
    They are really apples and oranges. The G2 is a beefy PU alpine boot, the Radium a light but stiff Pebax construction.The two materials react quite differently, the G2 having a more solid, heavier, damp feel while the Radium has a light, more reactive, more elastic feel. Having said that I’d say that stiffness is comparable unless it’s quite cold when the G2 will get stiffer, being PU which is more temperature-sensitive. Sorry to be vague but as I’m sure you know that there is no science to flex index and these two boots are a very different construction.

  53. Lou Dawson July 25th, 2012 9:56 am

    Good points Paul!

  54. Mile July 25th, 2012 10:42 am

    I knew it wouldn’t be a direct comparison, but looking for something stiffer than my Radium’s for lift skiing (damn kid). Also, could you comment on how Garmont’s alpine boot fit compared to the Radium (which fit me perfectly out of the box). If the G2 is comparable in flex to the Radium, perhaps the G1 in a 130 flex?

  55. Paul Parker July 25th, 2012 12:23 pm

    Either the G2 or 130 would be a great alpine choice for you. I’d go 130 you want something decidely stiffer. Both the 130 and G2 have the same fit, which is an alpine-boot fit with less room in the toe box as the Radium, but similar. You might also think about Deliriums–that is my lift-served/sidecountry boot and I find them to ski just as well as the alpine boots with a lot of adjustability and sole/binding options. Stiff and super comfortable.

  56. Paul Parker July 25th, 2012 12:26 pm

    Hey Doug,
    The Cosmos is scheduled for availability September 1. Check with your local shop or on the Garmont NA website (

  57. Sylvie J October 19th, 2012 9:59 pm


    I need some advice! I bought the Garmont Luster boots and had terrible experiences with them. I can’t walk or ski without having extreme fatigue in my quads. I read that the lean forward is 25 deg and I feel this is my problem; too forward. I tried one Garmont and one downhill ski boot (which I really like) on the other foot to see the difference and after 10 minutes, the quad of the Garmont side was bugging me big time while I was comfy on the downhill boot side and this is were I notice the lean differences in the mirror.
    Is there a way this can be adjusted or can you suggest an other boot that would have a lesser forward lean angle (if that makes sense…)?


  58. Lou Dawson October 20th, 2012 7:36 am

    Sylvie, that all makes perfect sense. Every boot is different. Every person’s leg shape and skeletal structure is unique. You probably have something going on with your calf shape or foot that is creating more angle. This is common for women, especially with shorter feet that also exacerbate the ramp angle of the binding (the shorter the foot, the more degrees of lean are created by binding heel being higher than toe.) If you want to stick with that boot, you need the services of a boot fitter who can change your boot angle and might even need to have a shim placed under the toe of the binding.


    Your problem is not caused by anything wrong with the boot, it’s just a problem of biomechanics.

  59. Sylvie J October 20th, 2012 8:43 am

    Thanks Lou.

    I live in Calgary and have a hard time finding a boot fitter. Can you suggest one? My boots are size 24 but too small. I can get a 24.5 Intuition liner for them and t helps. I froze badly at only -5C and lost three toe nails because they were too tight in the 24.
    As for the angle, if I can’t find someone to help with those boots, I might look at the Scarpa Gea RS which has an angle of 16 to 20 deg. instead of 25. I’d rather keep my Garmont though if it’s an easy fix and safe some $$$.



  60. Lisa Dawson October 20th, 2012 8:59 am

    Sylvie, I’ve had the same problem with another boot so I can relate to your pain. I’ve learned that there are three basics with properly fitting a boot: (1) the boot itself (is it the right model and size for your foot), (2) footbeds and (3) ankle flex. We solved my forward lean problems by making sure the liner was thermomolded properly. I use a foot bed to stabilize my foot and neutralize my stance. And, we were able to decrease the forward lean of the shell by a boot mod. Sometimes we put a spacer under the front binding to even out the lean. I’m lucky to have a master boot modifier if the house, and I’ve gotten the best results by going to a professional Pedorthist who specializes in backcountry ski boots. I highly recommend it. Good luck!

  61. Sylvie J October 20th, 2012 9:08 am

    Good info Lisa. Thanks.

    My other problem is I need orthotics to help with an issue on my left foot (pre-dislocation syndrome). So I wouldn’t get any adjustment from the footbed…
    If I find a good boot fitter in Calgary, I can discuss the options you mentioned.
    I’m getting good advices here. Much appreciated.


  62. Lisa Dawson October 20th, 2012 9:10 am

    Sylvie, we don’t know any bootfitters in Calgary. Any readers out there with a recommendation for Sylvie?

  63. Steve October 20th, 2012 3:13 pm

    Here’s a link to a Calgary bootfitters thread on biglines. It’s dated but most of the guys are still around.

  64. Sylvie J October 20th, 2012 5:35 pm

    Thanks Lou and Steve.
    I”ve discussed the issue last year with the Lou in Calgary but other than getting new boots, not much could be done in his view. But then again, the problem is much clearer to me now. It will be resolved eventually!


  65. Sylvie J November 4th, 2012 9:05 am

    Lisa, Lou.

    Just an update on my Garmont Luster boots issues.
    I went to SOUL SKI AND BIKE in Banff and Junior was awesome and did a great job fixing my boots. He added a second hole in the flat bar at the back of the boots allowing to be more straight instead of the original 25deg forward lean. He also moulded my un-mouldable original liners to give me more toes space. I then treated myself to boot warmers! I tried them yesterday and it was a lot more pleasant!

    I highly recommend him for boot fitting!

    A happy skier

  66. Lou Dawson November 4th, 2012 3:02 pm

    Nice to hear Sylvie, sounds like you found a real craftsman! Lou

  67. Frej January 15th, 2014 7:01 am

    I see there are some talk about the Prophet which I am about to purchase, but I am a bit new to tele, and I am a bit concerned with the size.
    The length of my feet measure 275 mm.
    If I pick a mondo of 27,5, will there be some space in front so assure the tele flex, or is this too snug so I should go up to 28 instead?
    Swedish tele guy

  68. Lou Dawson January 15th, 2014 8:03 am

    My guess would be a 28. Anyone else? Frej, can’t you just carpet test and figure it out in 30 seconds? Lou

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