Price: $

A smooth-riding and nimble trainer with a performance edge, the Karhu Flow3 Trainer Fulcrum features minimal cushioning and a firm ride.



The Karhu Flow3 Trainer Fulcrum is a nimble neutral shoe with a performance edge. Utilizing Fulcrum technology to promote an efficient ride, this lightweight yet durable shoe is a versatile option suitable for training, racing, and everything in between.

Model Number:

Weight: 8.3 oz (size 9)

Stack Height: Heel (18mm), Forefoot (13mm)

Available Widths: D=Medium

How It Fits (based on width D)

  • Sizing: Standard shoe size
  • Heel: Medium
  • Midfoot: Medium volume
  • Forefoot: Medium
  • Toe-Box Height: low
  • Arch Structure: Medium
  • Shoe Shape: Semi-Curved


The Flow3 Trainer Fulcrum is a moderate featured, minimum neutral shoe designed for training and racing.


  • CMEVA is compression molded EVA which is an industry standard midsole material designed to offer durable cushioning.


  • Fulcrum is a high durometer EVA wedge located from the heel to the midfoot. It is engineered to promote an efficient heel to toe transition by converting heel strike energy into forward momentum.


  • Open Mesh is utilized throughout the entire upper and provides breathability.
  • Welded Overlays around the midfoot support the contours of the foot for a snug and supportive fit.
  • Reflective Details increase visibility in low-light conditions.
  • Traditional Sockliner provides contoured support and cushioning.
  • Strobel Last with the upper stitched to a full length EVA board for a comfortable underfoot feel.


  • Wearable EVA Outsole with Compression Molded Rubber in key areas for optimal durability and shock absorption.

Footwear Performance Characteristics

Pronation Control: What's This?

  • Neutral
    • Min
    • Mod
  • Support
    • Min
    • Mod
    • Max
  • Motion Control
    • Mod
    • Max

Heel-Toe Offset (mm): What's This?

  • 0
  • 1-2
  • 3-4
  • 5-6
  • 7-8
  • 9-10
  • 11+

Stack Height:

  • Barefoot
  • Minimal
  • Low
  • Medium
  • High
  • Maximal


  • Road
  • Road-Trail
  • Hard Trail
  • Varied Trail
  • Soft Trail

Shoe Type:

  • Premium
  • Standard
  • Performance
  • Racing

Customer Reviews

Comments: These are a great pair of lightweight running shoes. I was new to both the Karhu brand and lower drop shoes in general, but after running three weeks in these babies, I am a true believer. As a mid foot striker, they have held up well to my runs up to seven miles, and I feel that they have the built-in support to go even further. The fulcrum technology works, and they even offer support for the fellow over pronators out there in a stylish, featherweight design. Each week, I add more miles with my trusty Karhus, and they were simply born to fly. Love them and highly recommend them.
From: Carl, Sydney, Australia. April 20th 2014

Comments: These shoes are definitely different. I purchased them after watching a number of karhu's videos and I have to say that "efficient" is definitely the word to describe them; however being an experienced forefoot striker these shoes weren't for me. I really liked the wide toe box on the shoe, and the minimalist upper that was very breathable. There is also a lot of cushion under the forefoot, but this cushioning system is very firm. After putting 30 miles in them the cushion showed no signs of breaking in, and was just to firm for my liking. Also when my stride would get lazy and I would land more mid foot, the fulcrum insert would feel like it was punishing my arch with how hard it is. It's no wonder you'd want to stay toward your forefoot. If you like a firm ride with a shoe that sort of guides your gait cycle, then this shoe my work for you.
From: Charles, Helotes, TX

Comments: I bought these on a friend's recommendation, he couldn't say enough good things about them. I put about 30 miles on them the first week, alternating days with my go-to trainer at the time, and have about 90 on them now. The next week they were the new go-to's, there's something really smooth about them. I am a mid-foot striker who gets lazy and sometimes hits the heel and it seems regardless of position these shoes help transition my foot through the whole motion. They almost propel you forward. Upper fits well, I have only worn them with socks as I don't run without them so I can't comment on how they would be sockless. The only con is that I had a couple blisters after my first run, but it was a one-day (7 mile) break-in and it really could have been due to the heat and humidity. Plus the color, the scream/blue, is fantastic, it's awesome. I liked these so much I bought the trail version and was just as happy.
From: Mic, West Hartford, CT

Comments: These are one of those shoes that hooks you a few miles into your first run with them. They are firm, but not punishing (like, say the first NB MR10s), with a nice bit of resiliency added. The fulcrum "technology" actually seems to function really well. You find yourself seeking out a midfoot strike - and when you do the footfall is silent and very smooth. The denser material that the fulcrum is made of adds a bit of stability that this neutral runner found rather pleasing. It's hard to describe, but your feet just feel solid and still as they go through the gait. The upper is nice and smooth on top of your foot, with nothing in the way of hotspots. Most people will want to hook a lace through the rearmost spot if you don't want slippage. Overall, this is a wonderful shoe - particularly if you want something that's no-nonsense, in the range of firmness of a Mizuno, and brings a unique sensation to the table in terms of the fulcrum-affected footstrike (very pleasing when you're running economically). An impressive effort from a company that hasn't even warranted being on my radar in the past. Check out the trail shoes built on the same platform as well!
From: Joel, Austin, TX, USA