I have the green Michelin latex tubes in my rear disc for that reason. They do 40mm ones.
Not quite as fast as the pink Vitoria ones according to testing I’ve read, but it’s marginal. And having a valve that is naturally the right length helps.
As for the front, with removable valve core tubes, you can get extenders which twist into the existing valve tube, then the core twists in to them. They’re a lot better than the one’s that just twist onto the open valve as you mention.
I saw the Michelin… But could only find them for thin tyres.
I’m running 25mm, didn’t know if that was to much.
Got any links for those stenard??
Ah, yes, you’re right. I’m still on 23’s, so they were ok.
If you mean the in-between valve extenders, then I use these: https://www.wiggle.co.uk/continental-valve-extensions Says tubular, but works just the same for tubes
Thanks.
So (dumb question)…I’m just making the removable bit longer. So 30mm is loads extra.
I don’t need 60mm to clear a 41mm.
That correct?
Yes. You remove the valve core, leaving just an open tube (which from what you’ve said is 48mm). You then screw in the extension to the open tube, then screw the original valve core into the extender.
So if you only need a bit of extra clearance, then yes, get the smallest extender you can find.
You can always put some PTFE tape on the thread when connecting the extender
Yeah I was just never a fan. Just seemed like something else to go wrong. I’ll feel better if it’s screwed in.
Tho I can JUST use the extender and remove it leaving …
Magic, appreciate that 
That’s what I do, I just use an extender to inflate them then take it off and carry it in my spares kit.
I use the ones where you leave the valve core in place and just unscrew the top so the pressure can push it down. That way I’m running a completely standard tube with fewer failure points.
Ps. I leave a bit of PTFE tape wrapped around the valve stem to get a better seal when I attach the extender.
I got a bit lost above, but having just bought this setup i wanted to get something clear. you guys are talking about the difficulties that are brought about by deep section wheels yeah? So the natural valve on the inners is not long enough? If that’s the case, then not something i’ll need to worry about with my standard stabiliser wheels … before i go ripping open my incoming packages and not being able to use them or something!!!
Yep
ta
Well… one was too long… and one was too short. Joys of deep fronts and disc wheels.
Oh for a standard set of wheels 
Thanks @JaRok2300 - I am tempted to leave it, like you said, trying to eliminate failure points. Only worry is unscrewing the valve when I remove the extender. Dont want that stress race morning. Maybe I’ll have some practice.
I use the valve extenders that you just screw on, leaving the cores as they are (but opened). What is the danger of this setup?
To perhaps answer my own question, I did have a panic at my last TT, the air wouldn’t go in, reconnected the pump about 4 times and eventually it worked. I’ve now read that if you poke something down to push down on the valve to take more air out of the tyre, this reduces the pressure and should make it work?
Do this!
I realised when I got to a race that my front wouldn’t hold pressure for more than 10 mins, changed tubes quickly and same happened so rode on my training wheel. Some liquid PTFE on the valve extender has sorted it out.
The completely hollow extenders shouldn’t really touch the valve core so the danger of it unscrewing them when you take it off is minimal.
I use the same set-up, you can either do what you did or I always pop the valve core a couple of times with my finger to make sure it isn’t “sticky” before blowing up any tyre, with or without extenders.
Yes, this is what got me to switch to “proper” extenders. I did use the “over the top” one’s originally, but found them too temperamental. Especially as I was on 50+mm rims so couldnt see any of the valve if I unscrewed the extender like mw22 is talking about. Whilst the approach of sticking a pin down the extender can work, if it didn’t I was left with the problem of having to take the tyre off completely to try and sort it all out, and I definitely didn’t want that stress on a race day morning.
The final time I actually did change to the “proper” extenders, on taking the tyre and tube out, and then the over-the-top extender off, somehow the valve core had done itself up again over time, which is why it wasn’t inflating. So that’s another freak occurrence that I’d rather avoid.
Ive got the proper extenders on order. I am fortunate I can see the current core valve.
But I’ll have a play with both. I just want most reliable with least risk/stress to me pumping them on race day.
(And also an easy solution should I get a flat and need to swap em out)
Really useful info as always
