Mountain Biking - Lower pressure tires = faster wearing?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




Drunken Chicken
10-20-05, 10:38 AM
Hi everyone,

I was just wondering if the following is true: Lower pressure tires = faster wearing? I ask this because my Specialized Sport 2.2s have hardly worn away at all over 7 or so months, but now in this last month, I found the rear one really wore away (still has 40% tread in it, but last time I looked at it and checked it's tread (a month or so ago it looked like it still had 70% or so left...). I have been running a fairly low pressure in this last month and riding 2 hours of urban every weekend (i.e., I rode my low pressure tires on asphalt) and about 5 hours of trails every weekend. I've noticed the tires stick a lot better and it makes for funner rides because I can ride faster without worrying about slipping.

Any comments? I'm trying to use up the least amount of money possible, as I don't get too much pocket money, so I'd prefer to run higher pressure and sacrifice the benefits of low pressure rather than run low pressure and have to buy a new pair of tires for 60 euros.

Thanks,
-DC


LowCel
10-20-05, 10:54 AM
Not sure about how pressure affects wear but it you should replace your tires well before they get to the 50% mark. When you lose 25% of your tread you lose about 50% or so of the tire's original performance.

Quadzone.com
10-20-05, 11:01 AM
You have more tire contact on the ground running less air so I would say yes. Same goes for cars and trucks. You'll wear out a set of tires in no time not running at correct pressure. I like running lower pressure in my bike tires but after getting lots of flats I"m forced to run a higher pressure than I like.

It still blows my mind that I run 6 PSI in my ATV tires and 45 in my skinny narrow MTB tires... .LOL


Drunken Chicken
10-20-05, 12:31 PM
Not sure about how pressure affects wear but it you should replace your tires well before they get to the 50% mark. When you lose 25% of your tread you lose about 50% or so of the tire's original performance.
It's mostly the knobs in the center that have worn away, the actual sideknobs still have around 75% left in them.
Anyway, can anyone reccomend some cheap yet OK tires which come in 2.35", would fit my Hardrock, and are good in dry conditions, with rocks and roots as well as simply dirt trails?

Thanks

ghettocruiser
10-20-05, 02:34 PM
I'd have to say no. More of the tire in contact with the ground ought to spread the wear around more and effectively prolong the tread life.

There is probably a correlation, though, as when I ride my MTB on the road I crank the pressure up, and the extra miles eat up the tread pretty fast.

the wonginator
10-20-05, 02:58 PM
i was blown away when i could run 60 on my bike when cars run 32 as a rule of thumb :|

hondafan
10-20-05, 06:33 PM
i was blown away when i could run 60 on my bike when cars run 32 as a rule of thumb :|

Pressure is inversely proportional to volume. Therefore, the smaller the volume, the larger the required pressure.

the wonginator
10-20-05, 07:58 PM
yeah it makes sense.

cooker
10-20-05, 08:12 PM
Lower pressure means more stress on the sidewalls as they bulge on every rotation.
R

clifford_bgrddg
10-20-05, 09:40 PM
Hondafan is dead on. bravo. way to go public school! Boyle's Law

badsac
10-20-05, 09:49 PM
Not sure about how pressure affects wear but it you should replace your tires well before they get to the 50% mark. When you lose 25% of your tread you lose about 50% or so of the tire's original performance.

For real? Whether you're sliding with new tires at a higher speed, or worn tires at a slower speed, you're still sliding, pushing the limits, and having fun. I replace my tires when they're buggered.