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Old 10-17-09, 07:16 AM   #1
agc1976
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Ideal tire pressure for 32mm tires on fitness hybrid?

How many PSI should I be aiming for? The tires spec a max of 100PSI and I'm 206lbs if that helps...
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Old 10-17-09, 07:24 AM   #2
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I usually run maximum pressure for road riding.
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Old 10-17-09, 07:33 AM   #3
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I run 85# in my 40s, and 35s. Which is Max per the sidewall.

I don't subscribe to running less than that until I get over 40mm, and even then it would have to be for some pretty rough terrain.
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Old 10-17-09, 07:48 AM   #4
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Quote:
Originally Posted by qmsdc15 View Post
I usually run maximum pressure for road riding.
Why? That's not always necessary. You could very well be overinflating. An overinflated tire is more prone to punctures, has a slightly lower rolling resistance and can give a harsh ride.

Proper tire pressure is going to vary by tire and how much load you're placing on it.

In general, the more you weigh, the more pressure you want/need.

Your rear tire should almost always be inflated slightly more (about 5-10psi) as it takes a heavier load than the front.

Start with about 80% of the manufacturer's max pressure recommendations and adjust from there. Its a large trial and error thing. If the ride is too harsh, lower the pressure. If you get pinch flats, or find that it is a bit difficult to roll, increase the pressure.

As a 210lb rider, I typically run my 700x28s at 85/75psi. On the stock tires, the max recommended was 120psi. I got way too many flats. They were overinflated and too easy to puncture. At 80psi, not so much.
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Old 10-17-09, 09:42 AM   #5
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Quote:
Originally Posted by Wanderer View Post
I run 85# in my 40s, and 35s. Which is Max per the sidewall.

I don't subscribe to running less than that until I get over 40mm, and even then it would have to be for some pretty rough terrain.
The OP specifically asked about inflation pressure for 32 mm tires with a maximum inflation pressure rating of 100 PSI.

Last edited by Barry in GA; 10-17-09 at 10:04 AM.
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Old 10-17-09, 09:56 AM   #6
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Read the rest of my comment, before quoting out of context.
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Old 10-17-09, 10:08 AM   #7
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At 206 in 32's you're probably going to be most comfortable and have the lowest rolling resistance somewhere in the 80-90 psi range on the rear, with the front inflated to 90% of the rear pressure.

As a comparison, I'm ~240 and ride 28's and use from 95-110 on the rear, depending on the ride, longer rides get lower pressure (for more comfort) and shorter, faster rides, higher pressure.
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Old 10-17-09, 10:13 AM   #8
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Originally Posted by Wanderer View Post
Read the rest of my comment, before quoting out of context.
The quote was completely accurate, but I edited my previous post to eliminate that argument.

Your post about inflation pressure for 35 / 40 mm tires with a maximum inflation pressure rating of 85 PSI has nothing to do with the OP's question about 32 mm tires with a rating of 100 PSI.
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Old 10-17-09, 10:49 AM   #9
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agc1976,

You asked about the ideal inflation pressure for 32 mm tires with a maximum inflation pressure rating of 100 PSI on a fitness hybrid.

My wife and I ride fitness hybrids with 32 mm tires with a maximum inflation pressure rating of 110 PSI. My weight is similar to yours and my wife is about 140 lbs.

We mostly ride on smooth asphalt or concrete MUT's. After trying a wide variety of inflation pressures, I run 90 PSI front and 100 PSI rear. My wife likes 80 / 90 PSI. I am not saying these inflation pressures are "ideal" for all riders / bikes / tires / surfaces, but they work for us.

If you ride rougher surfaces, lower pressures might be more comfortable.

My opinion, YMMV.
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Old 10-17-09, 06:39 PM   #10
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The suggestion that a tire inflated to the maximum recommended pressure is prone to puncture is erroneous.
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Old 10-17-09, 08:40 PM   #11
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I run 85# in my 40s, and 35s. Which is Max per the sidewall.

I don't subscribe to running less than that (max, or 85 PSI, whichever is lower) until I get over 40mm, (at 32mm, the OP's tires are not over that ) and even then it would have to be for some pretty rough terrain.



The whole quote - with additional emphasis

Also, I run 35mm front, and 40mm rear, and avoid a pressure differential because of that. (When I ran 40's all the way around, I ran about 5# less in the front. Running with less pressure, resulted in more vague steering, and handling. I also find that by running near 20% less than max, in 100# or less tires, resulted in pinch flats on sharp bumps like roots under blacktop. I don't like pinch flats, as they are totally avoidable by running at max pressures on the sidewalls. Running at max pressure, I find I have far fewer tire problems, and much better handling (I don't play in the mud).

When I was running 1 1/4" tires (32mm), running at max pressures of 90 and 100, I still got an occasional pinch flat - keeping them at 110# stopped that.
p.s. I weigh 190, and my bike (under normal circumstances) approaches 50#.

Last edited by Wanderer; 10-17-09 at 08:44 PM.
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Old 10-18-09, 05:32 AM   #12
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This is all great info. Thanks everyone for the replies.
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Old 10-18-09, 06:31 AM   #13
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I have mine set at 80 psi.
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