Road Bike Racing - Tire Pressure

I run 120 in my ProRace2's.

I’ve recently had other racers tell me they use 140. I’m interested... by am leery of cornering at 140.

What about keeping 120 in front, and cranking up the rear?

What do you peeps do?

115, pro2 race's (http://two-wheels.michelin.com/2w/front/affich.jsp?codeRubrique=2092004115326&codePage=2092004115326_10092004141805&lang=EN) I've never seen a ProRace2.

[/petpeeve]

Here we go again. The side of the tire says to inflate to a max of 116 psi. Some say that much over that and you run the risk of blowing the tire off the rim while racing. Others say that is a bunch of lawyerly crap and you can go well above that. Still others say that more psi creates a less efficient tire. I'm with NomadVW (and Sheldon Harris) on this one. I run 115 in the rear and 110 in the front. I weigh 172.

100 front and back. I'm 136 lbs.

Yay!!!

Another tyre pressure thread!!!

135 front and back. no problems

110 front, 115 back, i weigh ~171 #

116-7 front / 120 rear and weigh 150. Pro2 Races, BTW :)

135 front and back. no problems
What do you weigh?

150 PSI


*post to piss off the "less PSI crowd"*

It really depends on your weight and the road conditions you're riding on.

I run 120 in my ProRace2's.

I’ve recently had other racers tell me they use 140. I’m interested... by am leery of cornering at 140.

What about keeping 120 in front, and cranking up the rear?

What do you peeps do?
I bet your rims aren't rated for that much pressure.

110-115 front, 115-120 rear @ 250

There's a nice little chart on the side of the PRace2 box that has a weight/inflation graph, that's what I go by. I'M hoping the tire people know more then I do.

General wisdom.

1. The lower the tire pressure, the more grip you will have, the higher the pressure, the less grip. (I'm not even going to touch the issue of rolling resistance)

2. The rear tire carries much more weight than the front tire does, so it should run at a higher PSI than the front.

I run the front at about 85-95 for max grip on the front, because a slip of the front will almost always result in a fall. A rear slip, however, is very easy to catch. Thats why I run about 120 on the rear so that hopefully the rear will slide before the front does.

We have a lot of rough chipseal, which will slow you down a lot at higher pressure. I run 110 rear, 100 front, and I weigh 178 lbs. I let the pressure bleed down to 95/85 or so during the week, then reinflate.

What do you weigh?

170 lbs

We have a lot of rough chipseal, which will slow you down a lot at higher pressure. I run 110 rear, 100 front, and I weigh 178 lbs. I let the pressure bleed down to 95/85 or so during the week, then reinflate.

You don't get pinch flats at 85?

There's a nice little chart on the side of the PRace2 box that has a weight/inflation graph, that's what I go by. I'M hoping the tire people know more then I do.

From the Michelin web site for Pro2 Race (http://two-wheels.michelin.com/2w/front/affich.jsp?codeRubrique=2092004115326&codePage=2092004115326_10092004141805&lang=EN) I found this image, is this it? It appears to be generic to all of their tires:
http://two-wheels.michelin.com/2w/images/justepression.gif

According to the chart, everyone 80 kg (176 lbs) and up should be inflating to 8 BAR (116 PSI).

I'm doing 120 front and back at 175 lbs, which appears to be about right.

You don't get pinch flats at 85?

Naw. I pump up for rides and races where I might not so easily see bumps. That 85psi is on the front. The rear just gets into the upper 90s.

you guys must have some really great pumps to inflate your tires to such exacting psi's

Yeah, with a decent pump, it's pretty easy on the last stroke to push down until the pump's valve pops open, then just do a partial stroke until you reach your target pressure.

Most of the time, I'm +/-2 psi or so. It doesn't matter.

I pump mine up and gauge it old school.... I Tap the side wall with my index finger until you can hear the tube wanting to burst out the side wall.....(my Gauge is broken on my Silca Pump Circa 1991)

I learned the hard way that if you overinflate a tire you can roll it off the rim in a crit. unlike a normal flat,
the deflate immediately. Was very fortunate not to go down and take others with me, but cracked an aluminum rim.

Funny timing of this. I usually go 100 front, 100-110 in the rear with my PR2. I weigh 147lbs. I got a flat in the front, and put in the C02 cartridge. It started to rain, and the ride felt noticeably awesome. It was even noisy, which I like, but it had better feel. Anyhow, got home and checked the pressure, it was about 80. I think tomorrow, I am going to try 90 & 100 and see how that feels.

Funny timing of this. I usually go 100 front, 100-110 in the rear with my PR2. I weigh 147lbs. I got a flat in the front, and put in the C02 cartridge. It started to rain, and the ride felt noticeably awesome. It was even noisy, which I like, but it had better feel. Anyhow, got home and checked the pressure, it was about 80. I think tomorrow, I am going to try 90 & 100 and see how that feels.

I was pre-riding a TT course with a friend, and there was this 4-mile section with horrible chip-seal. He was getting beat to death, and really falling off the pace. I convinced him to drop his tire pressure and he got a LOT faster. When we got back to the car, he was at 100psi in the rear, and he weighs 205.

I think a lot of people over-inflate for the road conditions. On a rough chip seal road, the higher pressure will really slow you down, aside from the discomfort. It amounts to constantly climbing and descending little 1.5mm hills.

On a rough chip seal road, the higher pressure will really slow you down, aside from the discomfort. It amounts to constantly climbing and descending little 1.5mm hills.

And energy being consumed in lots of little bounces.


I go for the highly scientific method of pumping my Pro2Races up to 120, then being a slacker about toping them up. I haven't the faintest idea how much I weigh. Probably like 80 kg... maybe?

The description of falling off the pace on rough chip seal really described a 6km stretch that I rode through last night. I normally run 110psi but I am going to drop to 95 rear and 90 front tonight and go for a ride.
The tires on my Roubaix have a tall sidewall (specialized Roubaix tires) and I think I could benefit from the added isolation.

I've been racing at about 90 PSI f/r this year. I should probably be running the front at more like 80-85, though. I'll probably start doing that. No pinch flats in ages, doesn't seem any slower (even on smooth roads, and most of the roads here are pretty smooth by my New Englander standards). I weigh ~125 lbs.

I used to run at 100/100-110. No point at all in having even that much pressure at my weight, except on a velodrome or something.

The tires on my truck say 80 psi on the sidewalls... at the max weight they're rated to carry.
Doesn't mean they have to be inflated to that pressure so you get beat to death riding around with no load in it however. Same thing applies to bike tires; inflate them to the pressure that handles well for your weight and the conditions you'll be riding in.

95 rear and 90 front made for some smooth sailing over a 10km chunk of crappy chip seal. The difference in road noise through the bars and seat is huge. Even if I'm not faster on this type of surface I'm sure not going any slower, and I am much more comfortable.
So I went and did my 30km loop after that and my riding time hasn't changed. Just that the ride is smoother. I weigh 158lbs though.

It amounts to constantly climbing and descending little 1.5mm hills.

I can see it now: WaterRockets MicroIntervals (TM)

the description of falling off the pace on rough chip seal really described a 6km stretch that i rode through last night. I normally run 110psi but i am going to drop to 95 rear and 90 front tonight and go for a ride.
The tires on my roubaix have a tall sidewall (specialized roubaix tires) and i think i could benefit from the added isolation.

wtf?

wtf?

I can't keep the same pace on the chip seal with large frost gaps as I can on new pavement. Picture a road made out of gravel that is stuck firmly, but no smooth spots and large cracks.
Maybe I'm not using the correct terminology. The Roubaix Pro tires have a tall sidewall compared to the cross section of the tire. I am hoping to let a few PSI out and improve the ride.

point. missed.

And energy being consumed in lots of little bounces.


I go for the highly scientific method of pumping my Pro2Races up to 120, then being a slacker about toping them up. I haven't the faintest idea how much I weigh. Probably like 80 kg... maybe?

That what I do. I go 110/120 front/rear then by the time I put air in again it's somewhere around 100s. Sometimes for the front I just squeeze it and make sure it's not going flat.

please look at the date of the post you juts replied to.

I know its an old post. I guees I could have started a new thread.
Anyway. Maybe its just that I have to ride crap roads. Any tips for tires on roads like these?
BTW, these roads will chew the tires on my R1150GSA up in 3500km.

3 years later???? For what it's worth, since then 90/100 is my standard for road. MTB & Track are way diff in either direction, psi-wise.

105 front, 115 rear. 23mm tires, 170lbs.

Jeez. I need to run less pressure. Currently running 110 f/r @ 130lbs :eek: