The Epic 8 came with Tyrewiz, not something I wanted or would ever buy myself and it’s not the kind of bike tech that would really be worth selling so I’ll probably keep it.
Heading to the BCBike Race in a few weeks and I used a rear insert in this race in 2024 so would like to replicate the set up.
Problem is I reckon the Tyrewiz won’t register correct pressures with the Rimpact insert pressing up against it.
Has anyone had success using Tyrewiz valves with foam tyre insert ?
Might be possible to cut a chunk out of the insert over the valve stem but I’d be hesitant to try this.
I’ve not taken the valve out yet but intend to in order to see if I can drill some lateral holes in the valve stem 
If it looks like the image below - maybe there’s enough room for air pressure registration along the slotted section…? hmmmm…
cheers
I believe that slot is all that is needed. It provides paths that can’t be blocked by the insert. Drilling additional tiny holes would add nothing. If the insert blocked this or any other valve, it wouldn’t be possible to let air out or check pressure with a gauge.
I have TireWiz(es) on my Zipp Hitop SWs and I run them with Vittoria AirLiners. It never occurred to me to even second guess this. As far as I can tell, they work just fine.
I have run them with Vittoria and Tubolite inserts and they work fine. My issue was that one of them was off from the other and all other gauges pretty significantly, so I was always having to mental math correct them.
thanks all for the replies - sounds like no valve drilling or insert cutting needed 
Afraid that didn’t work, when I removed the pump all the air stayed in the tire (with valve core removed)
Going to try replace the rubber wedge with a small O ring and see if that helps
That didn’t work either, ended up chopping a section out of the insert it, works now
