# 80 psi



## wilko (28 Oct 2009)

Been road riding for a few months now and have a hybrid that I pump the tyres up to 90 psi. Today I decided to take my old mtb along the canal path, but had no idea what pressure to pump the tyres up to, so I put 80 psi in them!! I have a feeling this is too high, so what would you recommend I pump them up to?


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## Norm (28 Oct 2009)

What does it say on the side walls? Mine are, IIRC, 40-65 and I stick 50 in them but every tyre is different (as is every bike, rider, route etc etc).


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## wilko (28 Oct 2009)

I didn't think to actually look on the sidewall! It says max psi 80 min psi 25, so I guess 50-60 psi would do it.


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## JiMBR (28 Oct 2009)

80 psi does sound on the high side.

As Norm says, every tyre etc is different.

I usually stick with 50-55 in mine, sometimes with slightly less in the front.


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## Norm (28 Oct 2009)

Experiment a bit. 

Higher pressure reduces the shock-absorption benefits you'll get from the sidewalls but too low and you can get snake bite punctures if the wheels hit the hard stuff. If the pressures are low enough that the tyres deform, that can make the bike feel very insecure on the tarmac.

But, if the range is 25-80, then 50-60 would be a good starting point.

IMO.


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## mr Mag00 (28 Oct 2009)

i dont like it so low on the mtb i hate the way the tryes squirm. i go high and feel far more in control


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## Cubist (28 Oct 2009)

mr Mag00 said:


> i dont like it so low on the mtb i hate the way the tryes squirm. i go high and feel far more in control


Until you hit some nice rooty track, or a few rocky steps.......


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## spence (29 Oct 2009)

40 is the most you'll need for off road, less will give you better grip. Even less if you're running tubeless.


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## Mr Pig (29 Oct 2009)

I like my off road tyres quite hard, about 60-65psi I think they're at. I don't do a lot of dare-devil riding and I prefer being able to batter rocks etc without getting punctures. It also helps to deflect thorns and stuff like that. You do get less grip on harder surfaces but for me it's bearable for the limited off road riding that I do.


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## mr Mag00 (29 Oct 2009)

> Until you hit some nice rooty track, or a few rocky steps.......


i allow the suspension to deal with that whilst i glide effortlessly.


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## wilko (29 Oct 2009)

I won't be doing any extreme off roading, just down the canal towpath, so I will try riding with psi 50 to start and see how we go. Many thanks for your replies.


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## Mr Pig (29 Oct 2009)

wilko said:


> I won't be doing any extreme off roading, just down the canal towpath.



You don't even need MTB tyres then. Get some puncture resistant commuters with a little bit of tread.


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## JiMBR (30 Oct 2009)

I can recommend 'Town and Country' from Continental...excellent tyres.

http://www.chainreactioncycles.com/Models.aspx?ModelID=18845


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## RedBike (30 Oct 2009)

MTB tyres rarely go much over 50/60, 80psi sounds very high. I'm guessing these tyres are more of a narrow hybrid tyre than a wide knobbly MTB tyre?


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## yashicamat (15 Nov 2009)

The Specialized FastTraks my Rockhopper Comp came with have a max of 85 PSI, and they're 2.0" IIRC. They are slightly oddball tyres though, "fast rolling off roaders". Replaced with some decent Maxxis ones since as the Spesh ones were useless in the gloopy stuff.


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## bauldbairn (16 Nov 2009)

JiMBR said:


> I can recommend 'Town and Country' from Continental...excellent tyres.



I looked at these - then went for the Michelin City's, although next time I quite fancy the Continentals. What's the grip like on tarmac?

Oh! My tyres are 1.85" X 26" and I have 75psi in the front and 85psi in the rear on tarmac. I take about 15/20psi out for towpaths though. Anywhere in the tyre walls pressure range should be ok Wilko, as others have said - experiment.


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## JiMBR (16 Nov 2009)

bauldbairn said:


> I looked at these - then went for the Michelin City's, although next time I quite fancy the Continentals. What's the grip like on tarmac?



Once they are bedded in, the grip on tarmac is brilliant.


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## lukesdad (22 Nov 2009)

Good all round pressure for off road tyres is 45 psi ( you ll still get grip but should minnimize punctures).


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## Chrisc (22 Nov 2009)

A friend recently decided to go with the 80psi max on his tyres as stated on the tyrewall. Bit bouncy but he got home ok and leaned his bike in the hallway as usual. An hour later there was an almighty bang and he found the bike with the front tyre off the rim, a six inch rip in the tube and a huge bulge in the rim. 
Obviously a bad idea to lean it against the radiator!


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## Jonathan M (25 Nov 2009)

Chrisc said:


> A friend recently decided to go with the 80psi max on his tyres as stated on the tyrewall. Bit bouncy but he got home ok and leaned his bike in the hallway as usual. An hour later there was an almighty bang and he found the bike with the front tyre off the rim, a six inch rip in the tube and a huge bulge in the rim.
> Obviously a bad idea to lean it against the radiator!



+1 for this! I used to run Mavic 231 rims, lightish weight jobbies, back in the 90's. With canti's this meant rim wear, & lots of it with weekly rides at all the MTB'ing hotspots, forget trail centres they didn't really exist then. Riding home from work one night I had the above happen, I'd pumped the tyres up that morning before going to work and simply the pressure had found the rims' weak spot. Probably got nothing to do with being near a radiator, more that the rim was worn and could only cope with an hour. Mine coped with about 9 hours on that day before it went bang!


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## lukesdad (25 Nov 2009)

Ive got some ritchey thumbs that ive had for a few years now they dont wear at all amazing things 26x1 s anybody know if you ca n still get them or their equivilents?


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## lukesdad (25 Nov 2009)

Sorry just found them Ritchey tom slicks they re grrrrrreat!


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## joshtp (11 Dec 2009)

i would say that 80psi is hugely high, i run 25psi in my 2.5 highrollers on my HT, i ride mostly XC/AM trails, and im about 9.5 stone, i supose a bit more would be good in smaller tyres, as would be for a heavier rider, or for smoother trails.


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## Speck (11 Dec 2009)

I believe Wilko has a Sirrus, mine came with Spec kevlar 700 x 28's


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## Valy (11 Dec 2009)

Yeah - 80PSI sound kind of insane to me. 

BTW - don't you get more speed with higher pressures? Following the logic that there would be less SA, therefore less friction?


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## yashicamat (13 Dec 2009)

Just to add, I offroad with my Maxxis 2.2's at 50psi - I find this gives some cushioning still, but protects against pinch punctures and means I can still roll along OK on the road sections.


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## GrasB (13 Dec 2009)

Coast down tests show that my 26x1.3" conti sports contacts should be at around 85psi front & rear, that's the maximum for the tyre, where as the 26x1.95" mitch' country gravel are about right at 45-50psi.


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