Road Bike, Cycling Forums banner
1 - 20 of 24 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
I am a 205 lb rider with Easton EC90 SL wheels on a Specialized Roubaix Pro bike . In the past ,in road races , I have used Vittoria Open Corsa tires with a minimum inflation of 115 lbs and a max of 145. I usually pump them up on a good surface route to 125. However in visiting the Easton site, it says Ican only pump up 25mm tires to 108 which is less than the minimum on my tires. No liability to attach, just want opinions on my 125 inflation ??? Any help appreciated-- thanks
 

·
Banned Sock Puppet
Joined
·
14,443 Posts
I am a 205 lb rider with Easton EC90 SL wheels on a Specialized Roubaix Pro bike . In the past ,in road races , I have used Vittoria Open Corsa tires with a minimum inflation of 115 lbs and a max of 145. I usually pump them up on a good surface route to 125. However in visiting the Easton site, it says Ican only pump up 25mm tires to 108 which is less than the minimum on my tires. No liability to attach, just want opinions on my 125 inflation ??? Any help appreciated-- thanks
See link below and enter your info in the 2nd box. Assuming 20 extra pounds for bike, water bottles, etc., that would bring you up to about 225lbs. If you are more upright, use the 40/60 weight distribution. If you like a more aggressive race position, use the 45/55 weight distribution:

Bicycle tire pressure calculator

You can probably use less pressure than you think without any sacrifices in speed or pinch flats. You can certainly use less pressure in the front - you don't need bomber pressures there!
 

·
Doesn't like subtitles
Joined
·
3,808 Posts
I'm sure you'll get more detailed answers but I wouldn't worry. Max inflation for a wheel usually includes a pretty generous safety margin and if you haven't experienced a problem so far, I would think you'd be OK.

This will also I'm sure set off a tire pressure debate. I've never felt the need to pump my tires to more than about 100, except for my indoor trainer tire.
 

·
Registered
Joined
·
20,781 Posts
I am a 205 lb rider with Easton EC90 SL wheels on a Specialized Roubaix Pro bike . In the past ,in road races , I have used Vittoria Open Corsa tires with a minimum inflation of 115 lbs and a max of 145. I usually pump them up on a good surface route to 125. However in visiting the Easton site, it says Ican only pump up 25mm tires to 108 which is less than the minimum on my tires. No liability to attach, just want opinions on my 125 inflation ??? Any help appreciated-- thanks
I would follow Easton's recommendation. It probably means the rim sidewall isn't designed to handle pressure's that great. You could be looking at a rim failure.

Although I'd be more worried running a carbon wheel with 16/20 spokes at your weight. :shocked:

For conventional tire systems the tire pressure must stay within the tire manufacturer’s specified pressure, but never exceed the rim maximum pressure rating specified by Easton Cycling.

Road Bike Action | Tech Report: The Real Story Behind Carbon Clinchers
Two words: glass transition (Tg). Tg is the temperature at which the epoxy begins to deteriorate. In the case of clinchers, when the epoxy reaches Tg the outward pressure of the tire and tube can cause the rim’s sidewall to deform, potentially resulting in a catastrophic failure.

On a long descent, braking temperatures can reach 300 degrees Fahrenheit; resins not designed for high heat will reach their Tg point well below that, resulting in rim failure. Raising the Tg point of the resin is the obvious answer, and one that carbon clincher makers have been trying to perfect for years.

There are definitely some safety concerns to be aware of if you decide to take the plunge into the carbon clincher market. Riders over 200 pounds, or those who ride in especially mountainous regions where long descents could cause high braking temperatures, would be well served to research the testing that went into a wheel before purchasing one.
 

·
Banned Sock Puppet
Joined
·
14,443 Posts
Although I'd be more worried running a carbon wheel with 16/20 spokes at your weight. :shocked:
This.

Not trying to be snarky, just practical. You may want to read up on this part of Mike's wheel page here:

Wheels

There is a wealth of information here. There is also a lot worth reading if you go to the Wheels & Tires section and read some of the stickies there. Even if you have absolutely no intention of trying wheel building, this stuff is still worth reading.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #7 ·
I appreciate all the info here so far---should mention I am also 67 yrs old . I ride avg about16- 17 on my own--18 with a small group and can avg about 21 in a road race---I know I could do better losing the 20 lbs I always want to lose but??? Think I might try the Open Corsas at their 115 minimum and hope for no pinch flats based on the info here??
 

·
Registered
Joined
·
1,792 Posts
I run clinchers of the same size ~95 psi and tubeless ~90, also just over 200 lbs. My 50-yo creaky bones can't take the pounding of high-pressures.
 

·
Registered
Joined
·
317 Posts
I would follow Easton's recommendation. It probably means the rim sidewall isn't designed to handle pressure's that great. You could be looking at a rim failure.

Although I'd be more worried running a carbon wheel with 16/20 spokes at your weight. :shocked:

For conventional tire systems the tire pressure must stay within the tire manufacturer’s specified pressure, but never exceed the rim maximum pressure rating specified by Easton Cycling.

Road Bike Action | Tech Report: The Real Story Behind Carbon Clinchers
Two words: glass transition (Tg). Tg is the temperature at which the epoxy begins to deteriorate. In the case of clinchers, when the epoxy reaches Tg the outward pressure of the tire and tube can cause the rim’s sidewall to deform, potentially resulting in a catastrophic failure.

On a long descent, braking temperatures can reach 300 degrees Fahrenheit; resins not designed for high heat will reach their Tg point well below that, resulting in rim failure. Raising the Tg point of the resin is the obvious answer, and one that carbon clincher makers have been trying to perfect for years.

There are definitely some safety concerns to be aware of if you decide to take the plunge into the carbon clincher market. Riders over 200 pounds, or those who ride in especially mountainous regions where long descents could cause high braking temperatures, would be well served to research the testing that went into a wheel before purchasing one.
X2, great advice, I would not exceed the max tire pressure of the tire or rim mfr. CF is cool, but I don't usually buy anything CF due to aggressive riding at 190lbs and I'm not a pro rider.

...Not trying to be snarky, just practical. You may want to read up on this part of Mike's wheel page here:

Wheels

There is a wealth of information here. There is also a lot worth reading if you go to the Wheels & Tires section and read some of the stickies there. Even if you have absolutely no intention of trying wheel building, this stuff is still worth reading.
X2 :)

EDIT: I get my tire pressure settings by starting at max, ride a bit, drop 5psi front and rear, ride repeat until it starts feeling too mushy, like tire is starting to roll over in corners and in danger of pinch flat. Then I go back up until I find MY sweet spot tire pressure and on road bike usually front tire same or little less pressure than the rear. I should state that I run tubes in everything, tubeless is too much maintenance hassle for me, I just want to ride.
 

·
Registered
Joined
·
21,638 Posts
Think I might try the Open Corsas at their 115 minimum and hope for no pinch flats based on the info here??
I think you are confused about the meaning of "minimum pressure" for these tires. There really is no minimum but the marketing department has learned over the years that some customers think that higher tire pressure ratings mean "better tires." The 8-10 bar rating impresses some people.

I don't see where you mention what tire size you're using but at your weight you should be on 25 mm minimum and preferably 28 mm. The general guideline is that if you need more than 100 psi (7 bar) to prevent pinch flats then you either need wider tires or to improve your skills in avoiding sharp edges/objects.
 

·
Registered
Joined
·
9,658 Posts
Whatever you do.....ignore what's written on the side of tires. Kerry's theory about marketing meh be right but I figured it was "tradition" dating back to when conventional wisdom about size and PSI was more like conventional stupidity. If you need 115 to avoid pinch flats what you really need is bigger tires.
 

·
Banned forever.....or not
Joined
·
24,427 Posts
With 25mm tires, 100-105 should be more than enough, unless you tend to slam into potholes or curbs.

PS. The open corsa tires are racing clinchers. Why would you use those?
 

·
Registered
Joined
·
4,987 Posts
I thought this thread would be about Brexit and the economic impacts and resulting inflation?
 

·
Banned
Joined
·
7,744 Posts
I run those same tires at 80 and 85 psi with good results (for non-tubeless clinchers)

Regarding your second question--he said he is 67, not dead! Is there really anybody riding bikes so old that they are not into personal bests and competing with their peers?
With 25mm tires, 100-105 should be more than enough, unless you tend to slam into potholes or curbs.

PS. The open corsa tires are racing clinchers. Why would you use those?
 

·
A wheelist
Joined
·
11,324 Posts
The open corsa tires are racing clinchers. Why would you use those?
Why would he not use those? I'm older than the OP, don't race (anymore) and only use Open Corsa on my "best" wheelsets. Life's too short to use anything but the best tires - especially when I paid $33 each for my stash.

To the OP - read Kerry's last paragraph. If you need** more than 100psi you need wider tires. If your fork or frame won't take wider tires you have the wrong bike. IMO, start with 25mm tires inflated, at your 205lbs, to 90f/100r and try maybe 10psi less. Pneumatic tires are designed to cushion the ride, provide some suspension and provide traction. I can't imagine how miserable it is riding around on 125psi tires.

I use 70f/80r psi or a max of 80f/90r and the ride and traction are sublime.

**Need - to prevent pinch flats.
 

·
Forever a Student
Joined
·
4,963 Posts
16/20 spoke carbon wheels

200+ pound rider

Clincher tires

125+ psi

67 years old



Wow. I thought older people were more risk adverse than that.
 

·
Banned Sock Puppet
Joined
·
14,443 Posts
At 125+ PSI, why not just ditch the tires and ride on the bare rims?? :D
 

·
Banned
Joined
·
7,744 Posts
At 125+ PSI, why not just ditch the tires and ride on the bare rims?? :D
Geez, this brings to mind a far worse combination--ass holes on bikes!

I wondering how many of you here are old enough to remember 23mm tires and 125psi standards (have to be older than 10)
 
1 - 20 of 24 Posts
Top