How long are Dragonfly spikes good for?

I've used my VFs for 600+ miles. Still work fine

probably. ZoomX isn't very dense and packs down relatively quickly as compared to TPU or some EVA blends. I still think they're worth buying though.

Yeah I already have a pair and will continue to wear them. More a question of when to buy the next pair

gone wrote:

I've used my VFs for 600+ miles. Still work fine

I've heard this a lot. I don't assume the shoes magically crumble part after 100 miles or whatever it's supposed to be, but allegedly the foam loses at least some of the energy return... so sure you can still run in them but are you still getting the purported 4%+/- efficiency gain after 600 miles?

Folks that have a new pair to compare with an older pair (I'm thinking Seth DeMoor) say there is a noticeable loss of 'pop' by around 100miles. I think even Nike was confirming that with a 100-200mile estimation from some youtube 'heresay' reports.

I probably have around 100miles on my only pair, and they seem to be a bit more 'loose', but it is hard to judge how much 'pop' has been lost, without the luxury of another new pair at-hand to compare with. There is some just slightly noticeable creasing appearance on the foam.

When I *slightly bend them now along their longitudinal axis, or *slightly twist them, I can hear a faint creaking sound; meaning, in order to emit any such sound, there has been at least some compromise in overall energy return of the shoe.

*Any bending of the shoe you want to do very carefully, and not overdo it. When doing a bend test, I don't deflect them probably more than 1/2 inch. It is not just breaking of the plate that is at stake (which would require tremendous force and deflection), but it is the integrity of the plate/foam bond-line, and crazing (i.e., slight interlaminar micro-cracking of the carbon plate) which might eventually occur, over time.

Jack Daniels Calculator wrote:

*Any bending of the shoe you want to do very carefully, and not overdo it. When doing a bend test, I don't deflect them probably more than 1/2 inch. It is not just breaking of the plate that is at stake (which would require tremendous force and deflection), but it is the integrity of the plate/foam bond-line, and crazing (i.e., slight interlaminar micro-cracking of the carbon plate) which might eventually occur, over time.

That said, I imagine any bending of them I carefully do by hand is much much less severe than what they go through when hammering in them at race speeds on the road. It's not like they are 'egg shells'; they have to be fairly durable to put up with that abuse.

Jack Daniels Calculator wrote:

Jack Daniels Calculator wrote:

*Any bending of the shoe you want to do very carefully, and not overdo it. When doing a bend test, I don't deflect them probably more than 1/2 inch. It is not just breaking of the plate that is at stake (which would require tremendous force and deflection), but it is the integrity of the plate/foam bond-line, and crazing (i.e., slight interlaminar micro-cracking of the carbon plate) which might eventually occur, over time.

That said, I imagine any bending of them I carefully do by hand is much much less severe than what they go through when hammering in them at race speeds on the road. It's not like they are 'egg shells'; they have to be fairly durable to put up with that abuse.

On the road? The dragonfly is a track spike

Re: Vaporfly: My pair defo lost a bit of the feeling after lets say 100 miles, but how much of the actual performance that was lost is harder to say.

On the dragonfly, I think it's quite hard to put in the mileage requires to make the Dragonfly lose pop, but what I have seen on my pair was that the foam got damaged from hitting the track/collisions with other spikes etc.

The shoe is incredibly lightweight and versatile enough for races ranging from 1500 to ten thousand meters

I would buy another pair when you can find them at the 'right price'.

I have only maybe 15-18 on my Dragonflys, so I can't actually be very helpful in answering your question. I will say if I saw a really good deal I would snatch up a second pair.

I did that with my VFs and when I got to about 125 race miles on them; then first pair became my ParkRun and hard tempo days shoes. I am old and I do think they help with not beating my legs as much as a pair of light trainers.