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Author Topic: A good study about "Rolling Resistance" and what tires, PSI works best..  (Read 2013 times)

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Offline Darrinw2001

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good study of tires and psi for better rolling resistance.. I guess you were right Gregg, Chisel, etc...

Offline MtKillanewbieDH

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This has been around the forums before.

Anyways, don't believe the science, Darrwin...
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Offline $irWattZZZZ

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I have experienced the lower psi is better phenom and am drinking the kool aid, as far as wider is faster? Come on Schwalbie ::) If that is true, why are all the Pro XC racer boy's running 1.9's?

Offline Rocky Mountain OOTH

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I have experienced the lower psi is better phenom and am drinking the kool aid, as far as wider is faster? Come on Schwalbie ::) If that is true, why are all the Pro XC racer boy's running 1.9's?

1- tradition
2- weight
3- sponsors


Offline Darrinw2001

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I have experienced the lower psi is better phenom and am drinking the kool aid, as far as wider is faster? Come on Schwalbie ::) If that is true, why are all the Pro XC racer boy's running 1.9's?

because they are all weight wienies and think the extra .2 oz's of rubber may slow them down.... 

Offline ProEdgeBiker .

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i found that 30psi works well with my new tires

Offline ClintonRH

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I'm not sure I buy it completely. I think there's a sweet spot but less isn't always more. Go too low on the pressure and there's a definite drag that you can feel, especially with tubes. Not to mention that the tires start acting funny in the corners doing the grip-slip-grip-slip thing (plus the chance to roll/burp a tubeless). I've found that for me the sweet spot seems to be 30 front, 35 rear with my 2.2s but I'm a big heavy guy. I'm sure the lightweights will find the sweet spot to be even lower on their setup.

When I had tubes in my tires I'd start to notice what felt like a drag (like I was riding through sand constantly) if my rear got below 30. With tubeless I haven't had the problem since I've gone from losing 5-10 psi a week to losing 1-2 psi a week so the occasional top-offs are usually just a single stroke of the pump now. I never felt the drag effect on the tubeless setup but I did notice that if I went below 25 in the front and below 30 in the rear that the tires felt really wobbly and unsure in hard corners.

Offline hygieneboy

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Just like tires on a car. Thinner and higher psi yields better MPG on firm surfaces. Too wide or too low psi and you'll feel the weight and drag making you work harder. On MTB tires too thin and you sacrafice traction or will dig in deeper over soft terrain. The wider you go the better snow shoe effect you'll have. Somewhere in the middle is probaby ideal but it's also personal preference. I run 2.1" Kenda small blocks at 40 psi front/rear. The traction feels inconsistant at lower psi for me. They feel great everywhere and I don't notice any rolling resistance like I did on my stock fat knobby tires.

Offline $irWattZZZZ

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I have experienced the lower psi is better phenom and am drinking the kool aid, as far as wider is faster? Come on Schwalbie ::) If that is true, why are all the Pro XC racer boy's running 1.9's?

1- tradition
2- weight
3- sponsors
I have seen this argument before too Luis. When you are scratchin and clawin for a spot on the PODIUM, are you telling me you would let Tradition, weight or your sponsor derail that? Well maybe sponsor, but you would be running one of their skinny azzed tires :)

Offline chisel

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light, thin and low wins races. ;)    i like 24psi front and 27 rear.   tubeless of-course.  ;D

Offline Marcel Aguirre

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No thanks on the motorcycle tires for me...  did Schwalbe pay for that scientific study???

Offline Capetronics Inc

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good study of tires and psi for better rolling resistance.. I guess you were right Gregg, Chisel, etc...

Interesting read.

Maybe its just me but I installed  2.5" on my 29er for a while. I had been using 2.1" previously. Right from the start I felt the wider 2.5s sapped my energy faster and my over all avg speed dropped. I put the 2.1s back on and boy did I miss them. Speed increased and I didnt feel like I was riding through maple syrup. The 2.5" did performed much better in sugar sand.

Offline Marcel Aguirre

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Maybe its just me but I installed  2.5" on my 29er for a while. I had been using 2.1" previously. Right from the start I felt the wider 2.5s sapped my energy faster and my over all avg speed dropped. I put the 2.1s back on and boy did I miss them. Speed increased and I didnt feel like I was riding through maple syrup. The 2.5" did performed much better in sugar sand.
Don't think it was just you.  2.5 is like motocycle width tire.  Way more rolling resistance.... :-)

Offline CarbonCavy

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i found that 30psi works well with my new tires

I'm with you on the 30psi...I've tried 28 and other front rear configurations, but 30 works best for me.
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Offline Capetronics Inc

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Maybe its just me but I installed  2.5" on my 29er for a while. I had been using 2.1" previously. Right from the start I felt the wider 2.5s sapped my energy faster and my over all avg speed dropped. I put the 2.1s back on and boy did I miss them. Speed increased and I didnt feel like I was riding through maple syrup. The 2.5" did performed much better in sugar sand.
Don't think it was just you.  2.5 is like motocycle width tire.  Way more rolling resistance.... :-)
Yes you are right.....plus they were almost 1 pound each!!!  :)

 

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