Tire Pressure?
#7
Ha ha ha ha ha
Joined: May 2005
Posts: 4,555
Likes: 19
From: Gold Coast; Australia
Bikes: 2004 ORBEA Mitis2 Plus Carbon, 2007 Cannondale Bad Boy Si Disc, 2012 Trek Gary Fisher Collection Marlin WSD 29er Aldi Big Box (Polygon) 650b
I use what's recommended. I think 5.5bar in my 32mm and 8.5bar in my 23mm.
I guess your bike is much more comfortable than hers since you have less pressure. This is something you have to weigh-up before you change tyres. What do you want...less resistance or comfort? Getting both might be difficult.
If you want to roll with more ease, get some smaller profile slicks. Are you wife's wheels the same size? Ie. 26 or 700.
I guess your bike is much more comfortable than hers since you have less pressure. This is something you have to weigh-up before you change tyres. What do you want...less resistance or comfort? Getting both might be difficult.
If you want to roll with more ease, get some smaller profile slicks. Are you wife's wheels the same size? Ie. 26 or 700.
Last edited by giantcfr1; 10-12-11 at 10:25 PM.
#9
Senior Member
Joined: Oct 2008
Posts: 1,313
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From: Örebro, Sweden
Bikes: Monark sportser 1970, Monark sportser 1970ish, Monark folder, Mustand 1985, Monark Tempo 1999, Monark 318 1975, Crescent 319 1979, Crescent 325 c:a 1965, Crescent Starren 2002 (hybrid/sport), Nordstjernan 1960`s cruiser.
I wont argue about the recommended pressure, but max pressure (or even a bit harder) is the easiest way to make a bike go faster on even surface. Less rolling resistance + less friction = speed.
#11
Two-Wheeled Aficionado
Joined: Jul 2011
Posts: 4,903
Likes: 5
From: Wichita
Bikes: Santa Cruz Blur TR, Cannondale Quick CX dropbar conversion & others
Don't get me wrong. I'm mostly in agreement with you, but I would not have 100% confidence in saying that the fastest thing for any given tire is always max pressure.
I do, however, have 100% confidence in saying that the harshest ride you can get from a given tire is at max pressure!
I would leave the racing to racers and instead inflate your tires appropriately for their size, your total bike weight (mainly your body, but trailer or panniers would count), and your riding conditions. Smooth road-- yep, go high. Bumpy road, lower pressure but enough to where you don't get pinch flats. Offroad, same as bumpy road although if it's bump-free you can go lower pressure still to get significantly better traction.
Real world examples of my bikes:
Road bike has 700x25 Conti GP 4 Season. I weigh 175 pounds. I can run as low as 95psi in the rear for more comfort (and not get flats), but I can feel the tire squirm and I am much happier at 110psi. Despite a max rating of 130psi, I run no more than 120psi because I don't want to wear the center of the tire excessively.. the full tread is in fact intended to be used.
Hybrid bike has 700x35 Kenda Kross Supreme. I run max pressure on the sidewall, 85psi rear, on the road because this tire is made for mud and sand and it is terrible on pavement and this helps significantly. Gravel roads and basic cross-country riding, I run 70psi to balance rolling and grip. Technical singletrack I run 55psi unless there are a lot of big rocks or >1 foot drops / jumps. Then I run up to 70psi.
I don't currently ride a proper MTB but when I did you can go below 30psi offroad thanks to the huge volume of air in the tires.
All the above is rear tire only. For the front, decrease pressure by 5-10 psi depending on your riding position and thus weight distribution. Most hybrids will want 10psi stagger since the rider typically is fairly upright.
#12
Two-Wheeled Aficionado
Joined: Jul 2011
Posts: 4,903
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From: Wichita
Bikes: Santa Cruz Blur TR, Cannondale Quick CX dropbar conversion & others
I wasn't very clear about this point. Due to air volume, for the same rider and same conditions, a wider tire needs less air pressure than a narrower one. This is why a 2.3" MTB tire has a max rating of only 55psi, and a 23mm road tire is rated to 125-140psi.
In all cases you need more pressure if you are heavier, and less if you're not. If you get a flat make sure to inspect the tube even if you don't patch them. If it's a pinch flat you needed more air. Check your tires every ride, or at least every-other day.
In all cases you need more pressure if you are heavier, and less if you're not. If you get a flat make sure to inspect the tube even if you don't patch them. If it's a pinch flat you needed more air. Check your tires every ride, or at least every-other day.
#13
I have Marin Hwy 1 and currently run about 110 rear and 100 in front. I've run at 75 and 85 and honestly can't really feel the difference except for the road vibration being slightly more persistent, which seems reasonable. I'm going back to 75-85 this w/e and will probably stay there.
Rachel
Rachel





