MTB Tyres feeling flat- Mountain Kings + Hope Tech XC wheels

[tjdixon911]

Bit of an odd one, I have recently purchased some Hope Tech XC wheels (29"), which I am running some basic 2.2 Mountain Kings (no additional marks on the side wall, came off another bike) - I have them set up Tubeless and they are holding pressure, its just that the rear feels a little flat all the time, I have tried various pressures from 25-35psi - I don't know whether its the slightly narrower (than what I'm used to) rim width or the basic tyres (weak sidewalls?) that are creating this feeling any ideas?

Also what width tyre can I realistically run on the rim - (19.5mm internal & 24mm external width)?

[tjdixon911]

matt-ITR said:

So you are not losing air, just the tyre feel soft?

A narrow rim can make the tyre squirm, especially when cornering but shouldn't feet much different otherwise.
Probably just a more supple carcass. I went from tubed 40psi to 25psi tubeless and it felt like I had a constant flat tyre but I did get used to it.

No I am not loosing a significant amount of Air, I do check them recently and they may drop a few PSI over the course of a week or 2, I guess this can be down to temperatures?

richardxjr said:

Width is fine. First time tubeless?

If you're used to tubeless I can't see you wanting more than 30psi ever, so must be rubbish tyres! Non black chilli Contis are bloody lethal anyway.

Not first time tubeless, I've been running my Canyon Spectral tubeless for a few months (High Roller / Ardent TR tyres), my old XC hardtail has been running a tube in the rear for a longtime and tubeless front - so its the first time for a while that I've had tubeless rear on a HT.

loudlashadjuster said:

I have Mountain King 2.2s on my XC and I really don't rate them. I run with tubes but the sidewalls are like silk so it doesn't surprise me they feel squishy tubeless.

They grip OK but inspire zero confidence on the turn-in as, I presume, deflection in the sidewall gives very poor feedback. Th transition from straight to any kind of angle just feels...loose.

I was doing anything more on it than the odd trundle through the woods with the kids nowadays I would definitely be changing them.

This sounds about right - I purchased a Boardman Pro as a donor bike and these were included - I ran out of funds for tyres so just ran with them to get the bike rolling.

What tyre width can I get away with on this width of rim? I don't think I need to go much wider 2.25/2.3's.. I like what I have on the Canyon albeit they are 2.4's, would these in 2.25/3's be suitable for XC or are there better? (Not wanting to turn this into a What tyre thread...)

[tjdixon911]

vanordinaire said:

Welcome to my world . They all feel flat when you weigh 20 stone

I know that feeling - I was 20 Stone in 2002, managed to get down to and fluctuate since between 16-17 stone the same year - Last month I decided to join a Gym and get a bit of Personal Training/nutrition advice - I am now down to 15.5 stone with a target of 14.5 stone by end of July.