Let’s start with Presta valves, 2 questions, does anyone have the issue where they can’t open up the valve to inflate as the thread seems to have seized? Happened to me yesterday and I had to ride home slowly with a rear tyre that was wobbling all over the place. 2nd question, how much risk is involved in drilling a rim to fit schrader?

I currently have slime tubes at which have a smaller volume limit than the tyres I am running. I have a 2.125 tube and 2.2 and 2.3 tyres, will this cause any issues?

Finally tyre pressure, I have a purgatory control on the front and mountain king on the rear and both suggest 40psi+ even at 35psi the tyre feels rock hard, is my tyre pressure valve lying to me or are my expectations of the finger squeeze test on a tyre incorrect? I tend to feel that I need to be able to feel some decent give in the rear to get good grip.

Probably simple questions to some but I had an issue WI the back tyre wandering everywhere yesterday at a pressure I felt should be ok.

Thanks

I imagine the valves in slime tubes can clog up like tubeless valves clog with sealant. On tyres that size I’d run around twice your weight in stone in psi, only going higher if you get pinch flats or excessive squirm. Ignore the numbers on the sidewall, they make no sense and must surely be there just to cause confusion.

Thanks cgg, will give those pressures a try. You may be right about the slime clogging but it’s not visible on the threads, best solution I can see is drilling out the rim to fit the other valve type.

best solution I can see is drilling out the rim to fit the other valve type.

Or just open up the valve using a pair of pliers and grease/wd40 the threads once in a while?

I use undersize tubes all the time without issue.

When I used presta they would regularly jam slightly and need pressing in after unscrewing to break the seal. If you did that then it may be slime related. A few years ago I switched to shraeder and drilled my rims. Much better.

It’s a good point br, the thing is though, I do find the shrader(sp) much less easy to break or bend and seems lower maintenance.

Or just open up the valve using a pair of pliers and grease/wd40 the threads once in a while?

This. It should be part of your regular maintenance.

I currently have slime tubes at which have a smaller volume limit than the tyres I am running. I have a 2.125 tube and 2.2 and 2.3 tyres, will this cause any issues?

Absolutely fine, rubber is stretchy…

Finally tyre pressure, I have a purgatory control on the front and mountain king on the rear and both suggest 40psi+ even at 35psi the tyre feels rock hard

40+ psi is way too high, 30-35 max is what I’d suggest.

Thanks all, other than the valve maintenance it looks like I have been doing ok