MTB pressures. Interesting info.

[weeksy]

Due to listening to an 'expert' I'd dropped my pressure on MTB to 20/20. Not noticed any issues as such but reading this was quite enlightening

https://www.perpetualdisappointment.co. ... iders-use/

Most ews pros seem to be closer to 25-30 rather than the 20 I've been running, so I'm doing to go back up and experiment with higher numbers again

[Le_Fromage_Grande]

I like 30-30, much lower makes the bike hard work and cheap handling, much higher is puncture city

[Couchy]

Are the pro’s hitting stuff harder and faster so need more support ?

Tbh though as I ride to my local trail centre on tarmac I’m regularly at 25-30psi and I don’t drop them for the trail .last weekend I ride on the new bike which I didn’t get time to tubeless and I set them at 32psi. First run down the flows sections and I went quicker than I ever have. Pressure was irrelevant, be interesting to see how you get on

Looking at that article my 32psi is almost ideal, maybe that’s why I went quicker

[Mr Moofo]

There is a balance between grip and draggy - but it does depend on how sloppy the trails are.

Running near the 24 psi (for me) makes the SD slop easier to ride in. In the summer I would be nearer 30 psi - generally the front slight softer than the back.
I did run my rear at 17 psi post puncture - it gripped really well. But was a bit hard work. But less hard work than walking.

[weeksy]

Are the pro’s hitting stuff harder and faster so need more support ?

The first part is, well of course. But I don't know what all that means in reality, but you'd assume they and their sponsors have tested this sort of stuff a lot. Both in terms of grip, lifespan, etc

[MingtheMerciless]

Currently running 23/26 on my muds as it’s so dry, normally I’d be running 20/24 to get the tread squirming to help mud shedding. Summer time I run a 2.6 lightly treaded Rekon + on the front around 21/22 and the rear is a narrower 2.2 so 28/30. I weigh 76Kg ish.

[Taff]

That's a really interesting read, I've been running the Cannondale at 20 - 25 and really like the way that it felt but it is on 2.8 Michelin's which have a really stiff carcass.

The 0.31 - 0.34 ratio suggests that my tyres should be significantly higher pressure so as I'm still fiddling with the Whyte, I'll give it a go this weekend and see how that feels

[weeksy]

That's a really interesting read, I've been running the Cannondale at 20 - 25 and really like the way that it felt but it is on 2.8 Michelin's which have a really stiff carcass.

The 0.31 - 0.34 ratio suggests that my tyres should be significantly higher pressure so as I'm still fiddling with the Whyte, I'll give it a go this weekend and see how that feels

I think a few of us may be having a bit of a mess in this and coming weekends. The idea initially came about last weekend at 417 when i saw a local who was running a gazillion psi and i thought "Do they know something i don't about riding blues and pressures" and sort of snowballed from there.

I'll be the first to admit that this year i've got a little hung up on lower lower lower and 20 is about my peak at the moment.. As to whether it makes any difference or i'll even notice, is open to debate... but it's interesting to try things.

[Taff]

Earlier this year I noticed after a ride that I'd put a dent in my rear rim, I knew that I'd hit a few rocks and stuff but no bigger than what I'd normally ride, I checked the pressure and found 11psi.
I didn't notice the difference between 11 and 25 while riding.
I've also had times when I'm getting loads of pedal strikes so stopped to check the rear sag and found circa 50%

I'm either not good at feeling when things are not quite right or they really don't matter too much

[Flux]

Using the calc, I run exactly the right pressures on my trail bike and 2-3 psi harder than suggested for dh bike, I upped the pressures slightly on dh bike not so much for rim protection but to try and get it to roll a bit better.

[lostboy]

I posted about this in "the old place" after I came back from my first Canada trip in 2012. The obsession with low pressures was in full effect here (and continues to be) and the Canadians were just laughing at us for it. It was highlighted when we bumped into a couple of WTB test riders who said "why would you put less pressure in than the tyre is designed to perform at? Every piece of tread that's so specifically designed will hit the trail at the wrong angle." They went on to say that there were magazines that they wouldn't provide test kit as "they don't use it properly and then mark us down - we're not interested in their bullshit reports when the rest of the world can see how hard we test and the results we get."

[weeksy]

I posted about this in "the old place" after I came back from my first Canada trip in 2012. The obsession with low pressures was in full effect here (and continues to be) and the Canadians were just laughing at us for it. It was highlighted when we bumped into a couple of WTB test riders who said "why would you put less pressure in than the tyre is designed to perform at? Every piece of tread that's so specifically designed will hit the trail at the wrong angle." They went on to say that there were magazines that they wouldn't provide test kit as "they don't use it properly and then mark us down - we're not interested in their bullshit reports when the rest of the world can see how hard we test and the results we get."

I didn't really get a chance to test it much at the weekend as it was a proper slop fest, we were slipping and sliding on any tyres, any pressures and out on the bridelways the last think you worried about was how hard you could corner

I'll deffo be running higher this weekend though

[Mr Moofo]

I posted about this in "the old place" after I came back from my first Canada trip in 2012. The obsession with low pressures was in full effect here (and continues to be) and the Canadians were just laughing at us for it. It was highlighted when we bumped into a couple of WTB test riders who said "why would you put less pressure in than the tyre is designed to perform at? Every piece of tread that's so specifically designed will hit the trail at the wrong angle." They went on to say that there were magazines that they wouldn't provide test kit as "they don't use it properly and then mark us down - we're not interested in their bullshit reports when the rest of the world can see how hard we test and the results we get."

Interesting stuff - as I have never really bought into the low pressure thing. I can see of trials riding it gives grip in extreme conditions but then there has to be the balance between grip and drag. If a tyre maker designs a tyre , with a certain shape and side nobbles - surely they know best.
That said, I have a friend who insists on running at 45 psi - I tried it for fun. It may be the upper recommendation on Maxis - but it makes for an interesting ride.

[MingtheMerciless]

I posted about this in "the old place" after I came back from my first Canada trip in 2012. The obsession with low pressures was in full effect here (and continues to be) and the Canadians were just laughing at us for it. It was highlighted when we bumped into a couple of WTB test riders who said "why would you put less pressure in than the tyre is designed to perform at? Every piece of tread that's so specifically designed will hit the trail at the wrong angle." They went on to say that there were magazines that they wouldn't provide test kit as "they don't use it properly and then mark us down - we're not interested in their bullshit reports when the rest of the world can see how hard we test and the results we get."

Interesting stuff - as I have never really bought into the low pressure thing. I can see of trials riding it gives grip in extreme conditions but then there has to be the balance between grip and drag. If a tyre maker designs a tyre , with a certain shape and side nobbles - surely they know best.
That said, I have a friend who insists on running at 45 psi - I tried it for fun. It may be the upper recommendation on Maxis - but it makes for an interesting ride.

Interesting thing about Maxxis was that they specced a lower TP, thing was HR2's wouldn't seem to work unless you went below this pressure (?can't remember what it was it was so long ago). The problem was that you ended up ripping off side knobs and a few people tried warranty claiming and Maxis threw them out saying the tyres had been run too low.

[Taff]

I ran 30-30 at the weekend to see how it would feel and I think it was probably better than the 20-25 I was running.

One place that I really noticed the front gripping exceptionally well was on an off camber traverse that was covered in leaves. In my head this is on a par with riding on ice but the grip was perfect.
So it's higher pressures for the win

[lostboy]

I ran 30-30 at the weekend to see how it would feel and I think it was probably better than the 20-25 I was running.

One place that I really noticed the front gripping exceptionally well was on an off camber traverse that was covered in leaves. In my head this is on a par with riding on ice but the grip was perfect.
So it's higher pressures for the win

The WTB guys argument was "we've spent all this time developing tread and side sipes that bite the terrain beautifully if the sidewall is supported enough to give them the chance and you fuckers* basically run it flat so that it just folds up. It's not a fucking road tyre where you're trying to create a huge contact patch!"

*I was still very much "the Englishman" at that stage and we were all tarred with the low pressure brush!!!

[Taff]

I ran 30-30 at the weekend to see how it would feel and I think it was probably better than the 20-25 I was running.

One place that I really noticed the front gripping exceptionally well was on an off camber traverse that was covered in leaves. In my head this is on a par with riding on ice but the grip was perfect.
So it's higher pressures for the win

I'm the spirit of experimenting I increased the front to 35psi for a gentle bimble today (just over the recommended 0.31/kg) and the difference was really noticeable. Front felt hard, deflecting of rocks and roots and the tyre got quite clogged with mud. I think with a slightly lower pressure the carcass deforms enough to shed the mud and keep the year clear.

[weeksy]

I've been running roughly 28 both ends at bpw, Afan, 417. I've not noticed any lack of grip etc.