[Closed] As I understand it, you all LOVE a tyre question........

45 psi?! Are you sure you’re running them that high? Is off-road but you’re worried about pinch punctures than maybe 30psi to get better grip.

Yes tubeless is good - I run about 20psi front / 25psi rear on both my bikes. No pinch punctures since I’ve been tubeless.

Mk1 MK’s aren’t meant to be that good that I’m aware of -

i ran mk2’s in the black chilli compound 2.4” and I though they were pretty reasonable. However the Maxxis dhf/dhr2 I usually use are better.

Go tubeless. Will let you go lower on pressure. And lighter.

45psi is quite high. From your description of the terrain, I'd suggest too high. And energy is lost with pressures too high, pinging off stuff, bouncing the bike up & down, loss of traction. Lower pressures allow the tyre to conform more over the terrain.

I have no real experience of either of the tyres you mention, but one may roll slightly better than the other. But other factors will probably make a bigger difference, mostly your weight, fitness etc. There's a guy I ride with regularly who always had been, and always will be quicker than me. I'm probably (despite being 10 years older) fitter, but I just can't match his power output, just the way it is. The bikes/tyres are probably mostly irrelevant.

Am I running a bit high at 45 psi?

Yep. Most you ever need is about 30 (even with tubes) Offroad the tyre needs to deform over the ground a bit, so "generally" higher pressure is better for pure roadie stuff, but counter intuitively a lower pressure is better off road.

Also, are the two tyres any good?

Yep, if they're gripping they're good. In all honesty changing your tyres to ones with a lower tread will speed you up a bit, but losing the extra stone and getting fitter will speed you up even more..plus it's getting to the time of year where tyres like the RR will start to loose grip in the winter slop anyway.

I'm 16 stone and only run about 25- 30psi. Depending on tyre, wheel size, tubeless/tube and type of riding I'm doing.....

Ah, okley dokley, I'll definitely drop the pressure then.

Yes, sure it is that high. I got a half decent pressure gauge.

I am 76kg with not a load left to lose. He is just a lighter build than me. (Also fitter and done more cycling) It was just a hypothetical type question. I know I need to push out some more miles for sure.

I will suffer on the road back for sure though I suspect. I shall have to just try and find some more tricky stuff that will have him slipping and try and wear him out.

On seeing 45psi my reaction was “f*** me!”

Mine are around 20-23psi.

if you want to beat your mate I’d suggest some coaching (no one cares about the climbs, it’s all about the fun bits)

To add I’m around 12 - 12.5 stone so I think a similar ish weight. I’ve got a mate who is both fitter and lighter than me. I just let him go on the uphills as I accept I’m never going to keep up with him and catch him with better speed on the downhills!

Start with the pressures for sure. High pressure mean your bike is going to go up over every bump, root and rock which means you loose forward momentum to 'uppy downy' momentum... softer tyres mean you retain more of the forward momentum as the tyre does the deforming and doent require your entire bike plus rider weight to go up and over every small trail obstacle

This is a decent video explaining tyre pressure and how to get the best for you.

Well, this looks like it will be fun.

As you say, more grip. We like grip.

Thinking about it, it is quite bouncy down the hard lumpy stuff.

the tyre does the deforming and doesn't require your entire bike plus rider weight to go up and over every small trail obstacle

I have seen roadies going a bit wider and a bit lower psi for this reason too.

I had never thought about it having to lift my body weight in a vertical plane over the obstacle. Well mentioned. That sits in the brain that one.

Im 19.5 stone, or 124 kg, even on my ebike my tyres are only at 30psi.

Tyre pressure can be too low, just as easily as too high.

i used to go cycling with a much younger guy, who was fitter than me but not as strong.

i could outsprint him, every time, but on hills he would always leave me.

Fast forward a year, i had lost weight, he got heavier, and the climbing situation was reversed.

so I’d say, get a bit fitter and lose some weight, small changes can make a big difference.

this applies to tyres too, experiment with pressures to find what works for you.

You probably got the point now, but I'm the same weight as you and run about 35-40 psi on my all-road bike with 1.5 inch tyres...

What width are your tyres? I can't see it mentioned above. On my mtb I run 25-30 psi with 2.1 inch tyres, and 15-20psi with 2.6 inch. That's all tubeless though, so you'll want to add a bit (not sure how much, perhaps 20% or something)

I'm fat, run 18 - 20 psi and still use tubes.

Just experiment a bit with pressure, get a gauge and a pump and go for a ride.  Remember one gauges 20 may not be another gauges 20.  But if you stick to measuring it with just one gauge, you will find a pressure that suits you.

Fast tyres tend not to be grippy tyres, that's how the tread works.  At the end of the day you have to find a compromise that suits your riding and the terrain you are riding on.

14 stone, 26er Hobby Nics running tubeless at about 27psi here.

This is the mirror-land to my friend who started riding MTB from motocross and was moaning about getting pinch flats.  He was running 650b at ~17psi...

I was doing a lot of road riding earlier this year on my xc bike to build miles up.  I was running 45psi as it felt really fast on the road.  On one particular ride I decided to come back on an off road route.  I managed about half a mile before I stopped and let the tyres down to around 30psi as it was unbearable at 45 psi.  The bike didn't float over anything, it just bounced off all over the place.  So I would definitely start with dropping pressures.  I will add that that was with tubes.....after I set it up tubeless I lowered the pressures even more and it fees even better.

I know you said, but:

1) go tubeless, it rolls faster and allows you to get away with lower pressures.

2) 20-25 front, 25-30 rear unless it's rocky and you're running a HT. In which case put procore in the rear at least and still run these pressures.

3) 45psi will make you bounce off stuff more so on smooth ground it will roll better (but still not as well as a RR), but on lumpy stuff you'll be wasting energy bouncing off everything, particularly if you're on a hardtail.

4) if you ignore all the above, at least give lower pressure at the front a go, and lower rear pressure until you start puncturing. It will be slower than your mate, esp. if he's running tubeless, but it will be faster, grippier and more comfortable across rough terrain.

I used to run up to 45psi in the rear on tubes on a HT. I now run procore on the HT and 20-30psi, fast rolling on something like a RR.

Pay a shop to sort out tubeless if you can't be bothered faffing yourself.

Nice one guys, thanks.

I will definitely lower my pressures and play. I am looking forward to it. I understand what you are saying about the bouncing slowing me down. I will be out tuesday again (hopefully)

1) I have heard this now and will come onto that in the near future. I didn't realise there was quite so much love for it.

2) It is often rocky and I have a hardtail.

3) Cool.

4) No, he isn't running tubeless either.  I am his source of knowledge for such things.

Pay a shop to sort out tubeless if you can’t be bothered faffing yourself.

Pah, no chance. When I give it a go, I like to know what is going on. I will do it myself.

So, pressure discussed. Nice one.

Generally though, worth running something like a RR in the summer and the MKs in the winter?

Makes sense, right?

(In reality, I will probably wear out my old tyres in the garage first. (I think I have an old Psycho II (I might take a spare tyre with me on that day lol )) Then when they are worn down, I can call them a summer tyre eh?

Pay a shop to sort out tubeless if you can’t be bothered faffing yourself.

Pah, no chance. When I give it a go, I like to know what is going on. I will do it myself.

You might change your mind.  😉  Annoyingly there's quite a void between knowing the theory and applying it well, I've been running tubeless for many years but still get my LBS to tape the rims because when I do it myself they leak.  Everything else after that I can do, it's just the actual taping.

Have we mentioned compounds yet? There are of course several varieties of the same tyre out there. They all ride differently. The original Mountain King was fitted to many bikes as a factory option in a the basic "plastic" compound. Apart form have the same tread pattern though, it bears almost no relationship to the "made in Germany" Protection Black Chilli MK tyres from Conti that cost about 3 times the amount. I have been running an original MK protection on the front of my hard tail for coming on 4 years and it is still a fantastic all round tyre. On the back though I generally run something like a Maxxis Ikon 3c which is infinitely faster rolling but still has enough grip for most XC stuff (and more if you can keep the bike upright 🙂 ).

You might change your mind.

Hmmm, it does seem a faff. There seems an amount of 'hopefully' and 'should' and 'special pump'.

I shall visit this, but not in the very near future methinks. I have other things I need to spend money on for now unfortunately.

The original Mountain King was fitted to many bikes as a factory option in a the basic “plastic” compound. Apart form have the same tread pattern though, it bears almost no relationship to the “made in Germany” Protection Black Chilli MK tyres from Conti that cost about 3 times the amount.

Oh.

So, out of curiosity, it there a way to tell the difference?

It would be nice to know where I am for comparisons.

If it says "Made in Germany" on the side then it should be the expensive (and far superior) Black Chilli flavour. It should also say either Race Sport or Protection on there too. I think the MKs only came as Protection as the more expensive option. Happy to be corrected.

All the info you need...

https://conti-tyres.co.uk/mtb

Well, I can't find 'made in germany' on it.

Although they could do with a bit of a scrub.

Did they come on the bike or did you buy them yourself? If you bought them and they cost £50+ then they will be the good ones. If not, or they came fitted on the bike, high chance they are the less good ones.

Can't quite remember.

I think that they came second hand off a second hand bike.

From which I sold most of but kept some bits. My bike is a 'bitsa'.

The bike I think they came off was a Boardman 26" hardtail. But who knows if they were the original tyres? (Don't recall how old the bike was either.)

Actually, looking at this, you might be right.

https://www.thebikelist.co.uk/boardman/mtb-ht-pro-2011

I reckon it was about a 2010-2012 bike. (The Boardman) The specs look similar (same forks, drivetrain (different brakes)) etc that I ponced off it. So they might be off that bike.

Sounds like it matches with what you are saying.

So, well, if they are considered not all that great, am interested to try a decent tyre.  They seem pretty good to me. (But, as said, I AM pretty easily pleased)

A friend had a Boardman susser, exactly the same problem: basic Mountain Kings, totally failed to grip on anything like rock or roots.  Now those are not the grippiest materials but he described them as "actually dangerous".  Swapped to a pair of Minions and he's much happier.

If you want to replace the tyres without breaking the bank, the On-One own brand combo is apparently very good value for money.

They sound good. Think I will try and wear out what I have for now.

So, was brave and dropped pressure to 30 today : )

I see what you mean.

Kind of floats over lumpy stuff rather than argues with you.

Not so great on the tarmac though eh? But no surprise there. Looking to get to idless woods is about 5 tarmac miles each way. Joy. Reckon I will pump up and let down there when I go.

Next ride is more of a play than a loop, so will drop them further.

Finding it all quite interesting.

Time before last time out, my buddy was sliding all over in the RR.

He bought some MKII.

Their grip is much wider spaced than the MK I have. Last time out was no real test for them.

But yesterday mine were clogging up quicker than his for sure.

Based on very little knowledge, I would say mine were better as an all rounder than the MKII as we cover a variety of surfaces.

When going tubeless, do not faff about with tape - buy the rim strips that go with your rims, if available.  They work much better and you cannot really get it wrong.

Also bear in mind when choosing tyres that rolling resistance is not just down to tread and rubber compound but also the construction of the carcass.

It’s not uncommon for ‘special rimstrips’ not to exist. They definitely do for Bonty and I think Mavic have one but off the top of my head that’s all I can think of with a dedicated tubeless rimstrip.  Tape isn’t hard if you’re clean and methodical. For best ‘luck’, Rim needs to be alcohol-clean and tape needs the tension keeping up as you apply- so only spool off a few inches at a time. In theory, electrical tape should work really well and some can make it work really well, but it is prone to stretch which could bugger the job by spoiling its airtightness.  All in the hands... !  It does want to be as flush to the rim bed as you can make it and you really want something like a scalpel to make a little ‘x’ to get the valve through. Sloppy valve holes are a  standard fail.  There was a lot of discussion about this on Bez’s thread a day or two ago. I think it was all covered several times from different POV’s there...

Hmmm, it does seem a faff. There seems an amount of ‘hopefully’ and ‘should’ and ‘special pump’.

Not if if you do it right - Unless you are trying to make a really unsuitable combo work.  Older Conti’s can tend to have quite leaky sidewalls btw.  They may not be your best learning experience! 😉

What rims are they? That's what makes all the difference (and Mol's advice could be totally wrong, if it's a half-decent tubeless rim in the first plce)

It is def not a tubeless rim.

Mavic XC something somethings. I shall look them up when I get to the tubeless thing.

I reckon I shall start a new thread for that when I get round to thinking about it.

Which, tbh might not be too long the way we keep getting thorns.

I was more curious about the whole tyre pressure and tyre types.

short version of that is I reckon I will use up my MKs and will look at maybe buying something different for when it dries out. (Or just wear some cheap ones out that I have in the garage.)

I see that the MKs have limitations for sure.

They weren't clearing it all on monday:

[url= https://farm5.staticflickr.com/4831/31168425287_f3086c7727_n.jp g" target="_blank">https://farm5.staticflickr.com/4831/31168425287_f3086c7727_n.jp g"/> [/img][/url][url= https://flic.kr/p/PufjWT ]MTB[/url] by [url= https://www.flickr.com/photos/46850214@N08/ ]chuffedas[/url], on Flickr

Thats more paddle steamer than bike!

The MKs are OK but agree that they are poor on damp rocks and roots. The on-one combo is pretty good though would say the Smorgasbord is also a dry weather/summer tyre. It is reasonably quick though.

If you are thinking tubless get one of the Stans Kits with the rubber insert - foolproof every time on a combo of bikes/rims IME. The other good hint is to seat one side of the tyre with a tube and then only one side needs to seat when you pump it up!