Anatomy of a crampon

I recently had to lengthen my crampons to fit a new pair of a boots. This wasn’t the straightforward procedure I was expecting it to be: because of the design of the crampon I had to take the entire thing to pieces in order to fit the replacement part. It took me a couple of hours in the end, but I did learn a little bit about the construction of a crampon that I’d like to share with you.

The boots in question are the La Sportiva Olympus Mons heavy duty mountaineering boots that I bought for my Everest expedition in April. The boots are so big that standard size crampons don’t fit them without adjustments. I had already fitted longer straps to them prior to my expedition, but the length of the crampon seemed to be about right when adjusted to its maximum length, so I hadn’t bothered to replace the bars underneath the crampon with longer versions. Unfortunately the fit was quite snug, and it had been easy getting the crampons on the boot at home, but another matter at 8000 metres in the extreme cold when frostbitten fingers were a real possibility. A couple of times I struggled, and ended up having to ask my Sherpa Chongba to help me, which was a bit embarrassing.

Back home again I decided to fit long bars to replace the regulation size ones that come with the crampon. Sadly it wasn’t a case of sliding them out and sliding the new ones in. The photograph below shows what I ended up having to do. The crampon, in case you’re wondering, is a Grivel G14, designed for mountaineering and ice climbing.

Various bits of crampon, and the tools I needed to replace the bar on the bottom
Various bits of crampon, and the tools I needed to replace the bar on the bottom

The bit I needed to replace (1), shown here in both long and regulation size, is the bar which joins the toe and heel ends of the crampon together. As you can see, it has a number of holes in it to adjust the length of the crampon. It should slide easily into the groove on the left hand side of the crampon toe (5). It didn’t, which is why I needed the hammer to flatten a lug halfway along the bar which prevents the bar being extended to its full length (for people with smaller feet). Newer versions of the crampon have a notch the lug can slide through, but my older versions don’t.

Joining the crampon heel and toe sections
Joining the crampon heel and toe sections

The anti-balling plate (2) fits to the underside of the crampon and prevents snow building up and sticking to the bottom of the crampon, rendering it useless. Another one of these plates attaches to the heel of the crampon, as you can see in the photograph to the left. The bolt (3) slides through the very tip of the crampon and holds the anti-balling plate, front points, and toe end (2, 4 and 5) together. I needed both the spanner and allen key to detach these, and also the pliers to pull it through. The front points (4), as their name suggests, stick out of the front of the crampon and are designed for ice climbing and ascending very steep slopes. They’re not needed for gentle gradients and winter walking and can be removed, although I never bother as these particular crampons are comfortable for walking as well as climbing. The toe end of the crampon (5) has a wire bale that fits over a ridge which all rigid mountaineering boots have, and the ring attached to it by a strip of metal is used for looping the crampon strap through. The wire brush at the bottom of the photo was used to clean some of the parts. It’s not always possible to dry my crampons out before putting them away, and inevitably some of the parts rust from time to time. Although there is never enough to weaken the crampon beyond repair it’s good to rub away the rust before I use them again.

With the new long bar fitted and all the pieces put back together again, I needed to reattach the toe and heel sections of the crampon. This is the easy bit. A rubber accordion slides over the long bar to assist with anti-balling, and the end of the long bar fits under a spring loaded steel catch in the heel end of the crampon. The steel catch lifts up easily and is used for adjusting the length of the crampon to fit the size of your boot. As you can see from the second photograph, the heel of the crampon also has an anti-balling plate fitted to its underside.

Grivel G14 crampon fitted to La Sportiva Olympus Mons boot
Grivel G14 crampon fitted to La Sportiva Olympus Mons boot

The final piece of the jigsaw is the crampon strap, which fits into a yellow clip at the back of the heel. This is a fiddly operation in itself which needed pliers and a knife. I had already fitted longer straps prior to my expedition, but they ended up being too long, and I had lots of strap flying about which I needed to tuck in so that it didn’t trip me up. This requires manual dexterity and not a good task for freezing fingers. As well as fitting the longer bars I have also downgraded to mid-length straps which are long enough to fit around the larger boot, but not too long that there’s superfluous strap flapping around.

With the strap fitted the yellow clip snaps over a ridge at the back of the boot, and the strap is tightened for a snug fit. The third photograph shows the crampon attached to the boot before the strap has been tightened. Here the longest strap is attached to the crampon, and as you can see there is already lots of excess strap. By the time it’s tightened there is around 40 to 50cm of strap which needs to be tucked in – too much, which is why I opted for a shorter one.

I’ve had my G14s for nearly ten years now, and although they are no longer as sharp as they used to be, they still do the job. You can also buy spare parts for almost everything I’ve mentioned in this post. If you’re in the UK then I recommend Needle Sports in Cumbria, who sell by mail order. I had to phone them up for advice when I was fitting the long bar and found them very helpful. It was the man from Needle Sports who told me I needed to flatten the lug with a hammer.

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