Review: Inov-8 Trailfly 250 trail shoe

If you liked the Terraultra G 260, you will also like the Trailfly 250. These models are extremely similar!

Is the new Inov-8 Trailfly 250 an alternative to my beloved Inov-8 Terraultra G 260, which I bought in 2017, and maybe even the real successor? This popped into my head when I saw the Trailfly 250 in the online shop. In this test report, I will try to share my experience with you.

Trailfly 250 trail running show
The Trailfly 250 is a shoe for trail running, but imho also suitable for the road.

The Terraultra 260 at the time is and was a small sensation for me, because it combined 4 essential points that no other shoe delivered in this way.

  • It's a zero drop shoe, so the forefoot and the heel are at the same level. The heel is not lifted. As said this is 0mm drop.
  • Space in the forefoot area, but also a good cut in the midfoot area. Altra shoes are all too tight in the midfoot area for me.
  • It has a distinct but firm and direct cushioning.
  • The sole height, also known as "stack height", is low!

The last point, the low sole height, is particularly important to me. Because this lets me run more efficiently and injury-free. Yes, you read that right. I'll try to explain. The low height of the sole means that there is less space between the ground and the foot. In this shoe 9mm to be exact. This results in a smaller lateral angle. In other words, the shear forces acting laterally on the ankle are lower. In addition, you have a more stable stance, which is particularly important for trail running.

Zero-Drop shoes
The Trailfly G 270, the Terraultra G 260 and the Trailfly 250 are all zero-drop shoes.

The combination of good but direct cushioning and low sole height have made the Terraultra G 260 my favourite shoe for a long time. And I mean for a long time. This shoe was the most robust shoe I ever had. Nevertheless, at some point I had to get a new one.

1st Trailrunning Running Cup III in the Harburg Mountains
Felix Gertz 27.02.21
31,34 km 8:10 min/km 141 bpm 151 Watt
tredict.com
I run the Trailfly and Terraultra in the Harburg mountains, among other places.
There, the altitude profile is moderate on unpaved paths. I also like to use these shoes on gravel paths and even on the road.


Then Inov-8 released the Terraultra G 270, which has since been renamed to Trailfly G 270 and advertised it as the successor to the 260. I immediately ordered the 270 with enthusiasm. The Inov-8 Trailfly G 270 has undergone a few "improvements". According to the marketing department, the cushioning has been increased. This should make the runs less tiring, according to the advertising. I can say that exactly the opposite happened for me. Firstly, due to the different cushioning, it is no longer as firm and direct compared to the G 260, but much more stupidly, the sole is higher. As a result, the foot is now further away from the ground, the lateral angle and the shear force is greater and you feel more lifted. The stance is no longer as secure. No, this is a completely different shoe from the Terraultra G 260 perspective. Too bad, I thought. I didn't really run much in the Trailfly G 270. I never warmed up to them.
Soft sole
The Trailfly G 270 has a higher and softer sole compared to the Trailfly 250.

Since then, I've been thinking about the old good times with my Terraultra G 260 almost every other week. What great trail runs we have experienced together and he has never let me down. Even on longer asphalt routes, it accompanied me with confidence.

And now the Trailfly 250 is here! Wow, it looks exactly like the Terraultra G 260! Same sole structure, same cut at the toe cap, similar seams. Same flat sole height! Is this perhaps the worthy successor to my old beloved Terraultra G 260? Ok, the Trailfly doesn't have a "G", so no graphene sole, but I couldn't care less.

Identical sole
The sole of the Terraultra G 260 is identical to the Trailfly 250.

I think Inov-8 knows that the 260 wasn't all bad and is now relaunching a proven principle. Many production steps have already been proven. That's probably why the Trailfly 250 is relatively cheap.

The Trailfly 250's lug tread is identical to the Terraultra G 260's and provides decent grip, but without getting in the way if you ever run on the road. Of course, the Terraultra G 260 has graphene mixed in, which makes the sole very durable. The sole of the G 260 in the photo has just under 1000 kilometres on it. We will see how long the sole of the Trailfly 250 can last. The sole in the photo is only 12 kilometres old. :)

Same profile
The profile of the sole is the same on the Trailfly 250 and Terraultra G 260.

In general, I would describe the Trailfly 250 as a "natural running" shoe, as it does not prevent a natural running style and is suitable for wide feet. It has enough space in the forefoot area, both to the side and upwards. Since the shoe does not have a drop, it also allows for a natural foot strike. The sole height of 9mm is just flat enough, and in return you get cushioning. Thanks to the good but firm cushioning properties, the shoe can also be used for very long distances. It is suitable for ultra running, on the trail, gravel and also road. In other words, a real all-rounder.

Simliar design
Very similar design on the Trailfly 250 and Terraultra G 260.

The Trailfly 250 is pleasantly light at 287 grams for my shoe size of EU 44. So you don't get tired so quickly on longer runs. There are certainly even lighter shoes. However, they also have less cushioning and grip. My old G 260 is considerably heavier at 300 grams. But this is certainly due to the Kevlar reinforcement of the upper material. Kevlar is not exactly light.

Lightweight shoe
The weight of the Trailfly 250 is relatively light at 287 grams for shoe size 44.

By the way, according to Inov-8, the number behind the shoe name should indicate the weight of the shoe. I find it interesting that in the comparison of the Trailfly 250, Terraultra 260 and Trailfly 270, the actual weights do not match, even in terms of gradation. The G 260 with 300 grams is heavier than the G 270 with 278 grams, but it should be the other way round? So it remains a mystery how Inov-8 comes up with this and the weight designation seems to have been created in a marketing meeting rather than in the laboratory.

Shoe sizeDropSole heightWeightGraphene sole
Trailfly 250EU 44 / US 10,50 mm9 mm287 GrammNo
Terraultra G 260EU 44 / US 10,50 mm9 mm300 GrammYes
Trailfly G 270EU 44 / US 10,50 mm12 mm278 GrammYes

Unfortunately, there is one thing that really annoys me. Inov-8 seems to have problems with production consistency. The right shoe of both the Trailfly 250 and the 270 is twisted. Noticeable in newly purchased shoes. The left shoe stands up like a perfect one! I imagine that I have a different foot contact on the right side. In the video below you can see how much the right shoe is twisted.

Production flaw in the right shoe after new purchase. This one has a strong twist

Despite production errors, the Trailfly 250 will have a worthy place in my Tredict running shoe management and will hopefully do as many kilometres as the Terraultra 260. We'd rather not talk about the Trailfly G 270, which tires me out with its more indirect cushioning and higher sole height.

Disclaimer: I purchased all shoes myself and was not sponsored by anyone or anything like that.

This article also was published in German: Trailschuh: Inov-8 Trailfly 250 Testbericht

composed at 12/29/2022, 8:32:25 PM by Felix Gertz