Asics 2140s hacked!

I just bough a new pair of running shoes, the New Balance 890 V2s. I felt a bit like a collector as they're the brand new 'limited edition' Canadian version. More importantly I really like how they feel. Comfy but flexible; the cushioning is noticeable but stays out of the way. The forefoot isn't too wide either (I've had shoes where the laced sides almost touch).

Most importantly here's the flex in the 890s:

 Notice how they flex right through the arch area. This is different from earlier versions of padded shoes, which tended to have a rigid, non-flexible arch (no company in particular, they all did it). Of course all minimal shoes show flex in the middle. It's only the most recent training/padded stuff that's doing the same thing.



Now to the point of this post: Once I buy a new pair of shoes I usually get rid of my oldest pair to avoid clutter (I'm not that much of a collector). In this particular case I had some old Asics 2140s. They were decent training shoes I had used running with McGill XC. They're about three years old and forgot I still had them.

What my 2140s used to look like fresh out of the box

Clearly this shoe was nearing the end of its (natural) life

Before getting ridding myself of these runners I noticed they were actually in better shape than expected; asides from the top fabric being near the point of disintegration, the bottom half of these shoes were fine actually decent. There was no wear on the heels (I tend to wear out the forefoot instead, but even front half had miles left). Likewise the shoes still had some 'bounce' to them (thick foam never truly dies). Like I said, these shoes -like all training shoes available at that time- had a rigid arch support. I never liked that aspect but it was tolerable at the time.

A thought occurred to me: As an experiment can I make these shoes more like the NB 890s? These older shoes weigh an extra ounce. I was going to throw them out anyway, so what's the harm in a little meddling? There were two things I wanted to fix:

1) Create a more flexible arch

2) Remove some foam from the back heel, creating a rounder more natural heel.

Tools required: a knife.

Objective: cut a line across the plastic arch section and sever the 'spine'; carve away some of the foam (at a ~45 degree angle) so that less tread touches the ground better mimicking an actual heel. Here are the results:

Severed spine: check

Carved heel: check

Image from the bottom

To compare the difference of before and after, I only carved up one shoe at a time. So the first trial (i.e. me jogging on the sidewalk) was wearing one carved and one regular shoe. The second trial was wearing both carved shoes.

How did the revamped soles feel? It was a subjective experiment, but I had to say they really did feel more comfortable; I could tell the difference between the carved and original shoe. The landing was smoother since I could pronate (no sharp corners) and my foot's arch felt properly used. Closer to what it's like running on grass. Technically they were also a little lighter (because of the carved heel) but it wasn't really noticeable.

My big discovery was to see how easily modifiable old-style shoes could be. But now let's see if they fall apart. I'm going to run in them some more to check the long-term effects of my tampering.