Karhu Ikoni 2.0 Review
If you haven’t discovered Karhu running shoes yet, our Karhu Ikoni 2.0 review is a fantastic introduction. The Karhu Ikoni 2.0 is best described as a neutral shoe that has a degree of guidance. That makes it a suitable everyday training shoe for those that need no pronation support or a little bit of help. They are designed to be well-cushioned and durable enough for everyday training. The go-to shoe for regular mileage, good enough to be your only running shoe or within a rotation of running shoes.
What is the Karhu ‘Fulcrum’?
Karhu, born in Helsinki in 1916, has been developing footwear to help with forward propulsion since the inception of their ‘Fulcrum’ system in 1986. Nowadays nearly every new running shoe has a ‘rocker’, designed to keep the foot moving backwards, but only Karhu use their ‘Fulcrum’ to achieve this. The Fulcrum is in effect a firmer piece of midsole that is shaped like an upside down triangle. It sits from heel to mid-section of the shoe and as the foot lands it is pushed over the ‘triangle’. This encourages the runner to lift their foot up underneath them, which helps increase cadence and positions the foot under your centre of gravity on landing. It’s almost designed to ensure the runner ‘falls along’. The difference in feel between a rocker used by lots of brands now (Scott and Hoka were the first) and the Fulcrum is that a rocker encourages the runner to pull their leg back and ride over the shoe. The Fulcrum encourages the runner to lift their leg up. In my experience the Fulcrum helps me run with better form. My hips feel higher and I feel more upright and in control.
In my experience the encouragement to lift my foot up is more marked in the Karhu Fusion than the Ikoni. This has a shorter Fulcrum and the midsole is firmer, which must increase that feel. The Karhu Ikoni has a longer Fulcrum, which gives you more guidance through the gait cycle but the softer feel to the midsole means that you are slightly less aware of it. This doesn’t seem to make the Karhu Ikoni less effective than the Karhu Fusion.
How light on your feet the Karhu Ikoni can make you was illustrated by my daughter, who although she isn’t very heavy, hits the ground quite hard and noticeably sounds louder than other runners. The Karhu Ikoni made her lighter on her feet and her feet hitting the floor made no more noise than other runners in her latest run.
Cushioning Feel
I like firm shoes and ran my Fusions to death. They where a very durable shoe and I have enjoyed lots of miles in them. I don’t feel that I run any slower in the Ikoni. Although the midsole is softer than that of the Fusion, it isn’t ‘mushy’. This makes the Karhu Ikoni a versatile shoe. The softness of cushioning feels plush and nice when running with stiff tired legs first thing in the morning but on an evening steady run or fartlek session the shoe reacts well to the increased pace. Don’t get me wrong, the Karhu Ikoni isn’t a speed shoe, but you can still happily pick up the pace without feeling like you are ‘dragging a heavy shoe behind you’.
In my experience, shoes with a softer midsole aren’t great on hills. When you start to run up steep hills you can sink into the midsole and it’s like running uphill in sand. The Karhu Ikoni midsole isn’t super soft, but it still feels soft compared to a lot of shoes I would normally run in. What’s interesting is when I got to a steep hill I found that I was a bit more upright and my cadence was noticeably quicker. This is the type of good uphill running form that I am striving for, but I often find that I lean forward too much at the waist and I need to work at keeping my cadence high. In the Karhu Ikoni this just happened. I assume this is because the Fulcrum is encouraging me to lift my foot up when it touches the floor so I’m not riding the shoe as I would do in a shoe with a rocker. Although the AeroFoam midsole is soft, it is still quite bouncy and responsive. It is also quite flexible for a thick midsole so you can really push up the hills.
When running downhill the Karhu Ikoni promotes a quick cadence and upright running style. Your speed increases but you feel light on your feet with little impact.
Stack Height & Drop
The AeroFoam midsole used in the Karhu Ikoni 2.0 is 26mm at the heel and 18mm at the forefoot giving the Ikoni 2.0 an 8mm heel to forefoot drop. The forward propulsion that you get from the Fulcrum means that you aren’t aware of the 8mm drop and it doesn’t promote a heel strike. The shoes are designed to assist with good form and will help reduce the heel strike of a heavy heel striker making them lighter on their feet.
Karhu Styles
The thing that differs between Karhu styles is the length of the Fulcrum. The longer the Fulcrum the more guidance the foot is given through the gait cycle. The Karhu Ikoni 2.0 has a half fulcrum. It is a neutral shoe but offers some pronation support as it is stable in the heel with a full plastic heel cup and this stiffness runs into the midfoot guiding the foot. This will reduce early phase pronation but if you pronate later in the gait cycle then a shoe with more pronation support is likely to work better for you.
Shape & Width
The shape of Karhu shoes is designed using thousands of gait scans done by ‘Fit ID’. These scans are done in running stores when runners are looking to get new footwear. This is an ongoing process and the shape of the Ikoni 2.0 is slightly different to the original version. The lacing is asymmetrical, so it runs down the highest part of the foot. The forefoot has been broadened to allow more space for your feet to spread on impact. The big toe line is straight to allow you to toe off effectively and your toes to function.
Karhu shoes come in two widths a regular and a Hi-Vo. We currently stock Hi-Vo in the latest version, which means there is a higher volume inside the shoes. This is designed to fit feet that have a higher instep, greater instep girth, flatter feet and all round larger than average feet. Having worn shoes with broad rounded toe boxes like Altra and Topo for several years I like me toes to have space. So, despite having quite narrow feet I have always felt more comfortable in the Karhu Hi-Vo shoes. This is also true of our shop customers as the Hi-Vo sales are much higher than the regular width. Karhu shoes are small fitting compared with some brands. I use a UK 11.5 which is the same size as I would use in a Hoka shoe. Where as I am a UK 11 in Brooks shoes.
Shoe Feel
The fit of Karhu shoes is comfortable on lots of different shaped feet. So, scanning thousands of feet to work out the best shape for their shoes has helped them make a shoe that fits a lot of runners. The heel cup is well padded. Karhu’s in lock lacing system pulls the shoe in around the midfoot with a couple of tapes that are attached to the midsole and the laces. This pulls the upper in around the foot. The tongue is gusseted to stop it from moving. It is lightly padded but this offers enough protection from the laces. The 2 ply micro fibre mesh in the forefoot offers plenty of space so that your toes aren’t in anyway inhibited. The fit doesn’t feel snug. I found that the heel cup had a light touch to my heel. However, I have had no issues with slipping and haven’t had to use the extra lace holes to butterfly the laces to create a snug fit.
The Men’s Karhu Ikoni 2.0 weight’s 270g in a men’s UK8 and 227g in a women’s UK5. As the weight would suggest they feel very light on your feet.
As well as running up hills the other issue that I have with soft shoes is that they loose their bounce when you have been running a long time. So, when you are getting tired and need a little help the shoes flatten out. Although the Karhu Ikoni 2.0 isn’t as soft as others I was still interested to see if there was any difference in the propulsion that I felt from shoes after a few hours of running. To test this properly I ran for just over and hour and then put some pick ups in the later part of a run taking me up to two and a half hours. The forefoot of the shoes did feel a little softer and more flexible in the last few pick ups but no more than happens in the firmer midsole shoes that I usually run in. The firmer part of the midsole that forms the Fulcrum has a plastic piece under it to give it a firm base. There was no difference in how the shoes felt when I tried to increase the pace. I didn’t feel like I was sinking into a soft midsole. Quite the opposite I felt like the shoe was allowing my cadence to increase and I was able to float over the ground.
Summary
The Karhu Ikoni 2.0 is a naturally supportive neutral everyday training shoe that helps improve your form to increase your forward propulsion. The ride is plush and cushioned. They are versatile enough for long runs, easy runs, steady runs, tempo, fartleks etc… It’s a fantastic everyday training shoe.
—-
Other Considerations
New Balance 880: A all round shoe with a 10 mm heel to forefoot drop. Soft heel with a firmer forefoot. Available in three width Men’s and two width Women’s. Here is a link to our review for more information: https://www.northernrunner.com/blog/new-balance-880v12-review/
361 Centauri: The rocker offers a similar amount of propulsion to the Fulcrum. Here is a link to our review for more information: https://www.northernrunner.com/blog/361-centauri-review-361-centauri/
Hoka Clifton 9: Very soft cushioning with a rocker. Available in two width Men’s and two width Women’s. Here is a link to our review for more information: https://www.northernrunner.com/blog/hoka-clifton-9-review/
On Cloud Go: Very soft cushioning with a speed board to give some propulsion. Available in two width Men’s and two width Women’s Here is a link to our review for more information: https://www.northernrunner.com/blog/on-cloudgo-review/
Brooks Ghost 15: A more traditional feeling popular everyday trainer. 10mm heel to forefoot available in three width Men’s and two width Women’s. Here is a link to our review for more information: https://www.northernrunner.com/blog/brooks-ghost-15-review/
Altra Via Olympus: A broad rounded toe box. Made on Altra’s original last. Offers more cushioning than the Ikoni but, as it’s the only everyday road training shoe available in Altra’s original last it has become popular. Takes a few runs for the cushioning to soften up but, then gets better and better in our experience. Here is a link to our review: https://www.northernrunner.com/blog/altra-via-olympus-review/
Scott Pursuit Ride: A firm responsive well cushioned shoe with a rocker. Here is a link to our review: https://www.northernrunner.com/blog/scott-pursuit-ride-review/
Topo Phantom: 5mm heel to forefoot with a broad rounded toe box. Here is a link to our review: https://www.northernrunner.com/blog/topo-athletic-phantom-2-review/
Comments are closed here.