Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Clydesdales/Athenas (200+ lb / 91+ kg) Looking to lose that spare tire? Ideal weight 200+? Frustrated being a large cyclist in a sport geared for the ultra-light? Learn about the bikes and parts that can take the abuse of a heavier cyclist, how to keep your body going while losing the weight, and get support from others who've been successful.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 03-05-12, 12:26 PM   #1
magohn
Senior Member
Thread Starter
 
magohn's Avatar
 
Join Date: Jul 2005
Location: Woodinville, WA
Bikes:
Posts: 1,503
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Do you Max out your tire pressure?

Hi all

This weekend I had a second "tire explosion" while 15 miles from home. My Roubaixs original tires lasted 2000 miles and then the rear went out on me. In the last 6 months or so I have replaced the rear tire TWICE with similar Specialized Roubaix tires. Both have failed and at $60 a pop it aint funny anymore.However, could the problem be that I am over-inflating? The tires are rated to 8 BAR and I always pump approx 7.7 BAR into the tires before a ride. Now, I am in the 280lbs so I am wondering if the weight and the close to max pressure are the issue. Could it be that when I hit a pothole or similar that the tire pressure is increasing beyond the limit of 8 BAR and weakening the tire?

It was a little humorous I guess. Early Sunday morning, and as I rode past the church in Carnation, WA, BBBBAAAANNNNNNNGGGG - It literally sounded like a gunshot going off. Birds flew out of the trees, church-goeers were startled and the Clyde in his lycra was sheepishly apologising and pointing at the tire. My wife was thrilled that she had to get out of bed and come get me on a Sunday morning

Any thoughts on tire pressures for us bigger guys?

P.S. Enough of the $60 tires. Just bought a pair of Nashbar Road 2 tires for $15 a piece. Good reviews too.
magohn is offline   Reply With Quote
Old 03-05-12, 12:56 PM   #2
TrojanHorse 
SuperGimp
 
TrojanHorse's Avatar
 
Join Date: Mar 2010
Location: Whittier, CA
Bikes: Specialized Roubaix
Posts: 11,237
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 115 Post(s)
What kind of tires were you using?

I have Michelin Pro3 tires that are rated to 115 psi and I inflate them to 115 psi every time I go for a ride. I did blow out a sidewall one time (tiny little pinhole, not really a blowout) but I think that may have been related to a little incident I had on some jagged cement a week earlier. Anyway, the Michelins are apparently slightly infamous for blowing out sidewalls.

Hitting a sharp edged road hazard with any force is always a bad idea and can certainly result in the kind of issues you're facing.

Other than that, no tire blowouts of any kind up to 240#.
TrojanHorse is offline   Reply With Quote
Old 03-05-12, 01:04 PM   #3
magohn
Senior Member
Thread Starter
 
magohn's Avatar
 
Join Date: Jul 2005
Location: Woodinville, WA
Bikes:
Posts: 1,503
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Specialized Roubaix Pro tires at 7.7 bar (approx 110 psi) - same brand with 2 blowouts.
magohn is offline   Reply With Quote
Old 03-05-12, 01:04 PM   #4
Seattle Forrest
Senior Member
 
Seattle Forrest's Avatar
 
Join Date: Mar 2010
Location: Seattle, WA
Bikes:
Posts: 14,013
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 622 Post(s)
120 psi is fine.

Why are you spending $60 per tire? They'd better be really fantastic to justify prices like that. You can get legendary GP4000s in the ballpark of $30 per tire, if you buy them online from stores in the UK. FYI.
Seattle Forrest is offline   Reply With Quote
Old 03-05-12, 01:08 PM   #5
bobotech
Senior Member
 
Join Date: Jan 2012
Location: Spokane, WA
Bikes: Specialized Sequoia Elite/Motobecane Fantom Cross Team Ti/'85 Trek 520
Posts: 2,253
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
I have been buying my tires as used specials at the bike coop and inflate them to around 70-80 percent of rated. I haven't had a blowout but i don't ride nearly as much as most people here. But still, 390 pounds on a used 27x1/4 inch tire is rather testing the limits. Same with my 700c tires.
bobotech is offline   Reply With Quote
Old 03-05-12, 01:13 PM   #6
Yo Spiff 
Carpe Velo
 
Yo Spiff's Avatar
 
Join Date: Dec 2011
Location: Fort Worth, Texas
Bikes: 2000 Bianchi Veloce, '88 Trek 900, '88 Schwinn Prologue, '92 Schwinn Crosscut, '03 Diamondback Tandem, '94 Yokota Grizzly Peak
Posts: 2,514
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
I'm running 700x25 Vittoria clinchers rated for 115psi. I usually inflate them to 105-110.

I've sometimes had problems with rim/tire combos that just didn't get along and caused lots of pinch flats. Perhaps that's what is going on?
__________________
2000 Bianchi Veloce, 199x Bianchi Volpe, 199x Bianchi Boardwalk, 2010 Bianchi Milano, '88 Schwinn Prologue, '88 Trek 900, 198x Benotto Triathlon. '88 Schwinn Crosscut
Yo Spiff is offline   Reply With Quote
Old 03-05-12, 01:18 PM   #7
magohn
Senior Member
Thread Starter
 
magohn's Avatar
 
Join Date: Jul 2005
Location: Woodinville, WA
Bikes:
Posts: 1,503
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Seattle Forrest View Post
120 psi is fine.

Why are you spending $60 per tire? They'd better be really fantastic to justify prices like that. You can get legendary GP4000s in the ballpark of $30 per tire, if you buy them online from stores in the UK. FYI.
Weeelllll, The LBS was so understanding, supportive and positive when I wandered into their store 2 yrs ago at 320+lbs that I do like to support them whenever possible. They are a Spec. dealer and items such as tires are usually MSRP + tax. However, I think $120 on two tires that lasted (combined) less than 500 miles isnt going to fly anymore. I just ordered two Nashbar Road 2 tires for $40 shipped with almost 5/5 reviews.

I do prefer to use the LBS but in this situation I feel forced to go online.

People constantly aske me why I pull my brakes on descents and rarely go above 20 mph on a descent. This is the reason - 2 blowouts are unnerving. Not only the noise but the instant loss of control on the back end.

Heres a pic:


Last edited by magohn; 03-05-12 at 01:23 PM.
magohn is offline   Reply With Quote
Old 03-05-12, 01:32 PM   #8
magohn
Senior Member
Thread Starter
 
magohn's Avatar
 
Join Date: Jul 2005
Location: Woodinville, WA
Bikes:
Posts: 1,503
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Yo Spiff View Post
I'm running 700x25 Vittoria clinchers rated for 115psi. I usually inflate them to 105-110.

I've sometimes had problems with rim/tire combos that just didn't get along and caused lots of pinch flats. Perhaps that's what is going on?
Thanks but this is more than a pinch flat. It sounds like a gunshot and literally blows out the side of the tire (not just the tube).
magohn is offline   Reply With Quote
Old 03-05-12, 01:42 PM   #9
CraigB
Starting over
 
CraigB's Avatar
 
Join Date: Jun 2005
Location: Indianapolis
Bikes: 1990 Trek 1500; 2006 Gary Fisher Marlin; 2011 Cannondale Synapse Alloy 105; 2012 Catrike Trail
Posts: 4,081
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I've routinely overinflated mine for 30 years without any problems, usually to about 115 or 120 psi. On a variety of (usually inexpensive) tires.
CraigB is offline   Reply With Quote
Old 03-05-12, 01:47 PM   #10
tardman91
Senior Member
 
tardman91's Avatar
 
Join Date: Feb 2010
Location: Tampa Bay Area, FL
Bikes:
Posts: 329
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I wonder if it's a problem with your wheel? Is a spoke poking through the rim tape or something? I have Vittoria Pro tires that have a max of 145. I inflate the rear to 130 usually and the front to 120.
tardman91 is offline   Reply With Quote
Old 03-05-12, 01:50 PM   #11
magohn
Senior Member
Thread Starter
 
magohn's Avatar
 
Join Date: Jul 2005
Location: Woodinville, WA
Bikes:
Posts: 1,503
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Yikes - a search on the tire reveals lots of reviews of the Specialized Pro tire and its prone to "blow outs" (walls too thin) :

http://www.roadbikereview.com/cat/wh...4_2489crx.aspx

Many people with similar experiences with the tire. I will mount the "cheapos" when they arrive and inflate to the max and see what happens

You live and learn I guess.
magohn is offline   Reply With Quote
Old 03-05-12, 02:12 PM   #12
Mr. Beanz
Banned.
 
Mr. Beanz's Avatar
 
Join Date: Dec 2005
Location: Upland Ca
Bikes: Lemond Chambery/Cannondale R-900/Trek 8000 MTB/Burley Duet tandem
Posts: 20,030
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by magohn View Post
Yikes - a search on the tire reveals lots of reviews of the Specialized Pro tire and its prone to "blow outs" (walls too thin) :

http://www.roadbikereview.com/cat/wh...4_2489crx.aspx

Many people with similar experiences with the tire. I will mount the "cheapos" when they arrive and inflate to the max and see what happens

You live and learn I guess.
With the exception of the classic Armadillo, I wil never use a Specialized "road" tire again. I used S-Works after a rec from a bud, rolls nice blah blah blah. After 500 miles, first ride up GMR, the thing was missing a 5 inch chunk of rubber. Later found out it was a common problem with the tire.

I do run my tires at 120 psi. I do run an Armadillo on the rear of my bike. Rather deal with less flats. I recently place a "legendary" GP4000 on the front. Honestly , as I've always said, I see no difference in the ride. But guess what! I flatted, newish tire 400 mile (?). Who in the heck flats on the front tire onsmooth trail? I raerely flat in the front, this thing flatted in the front by way of small puncture. OK, a shotgun blast I can see but a small punctrure? Sheesh it's the front!
Mr. Beanz is offline   Reply With Quote
Old 03-05-12, 02:13 PM   #13
freighttraininguphill
Senior Member
 
Join Date: Jul 2006
Location: Northern California
Bikes:
Posts: 2,642
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Yikes! The tread pattern on those looks exactly like the Specialized All Condition tires that came on my road bike and Sirrus. Both bikes still have those tires, and I have noticed cracking in the sidewall along the bead just above the rim, even when the tires were fairly new. I never inflate these much over 100 psi, even though they're rated for 115-125 psi. I keep a close eye on the sidewalls too. When they wear out I think I'll try a different brand.
freighttraininguphill is offline   Reply With Quote
Old 03-05-12, 02:22 PM   #14
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 20,358
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 633 Post(s)
Only pushed the PSI on my 622-40 Nokian A10 tires to 6 bar ,
because the camping tour load
and rolling resistance said to me it was more work, below that.

47 wide tires, especially the 20" ones are fine .. just use the thumb
rather than the gage.

I just don't ride the Roadie bike much, as its not kitted out for rain.
fietsbob is offline   Reply With Quote
Old 03-05-12, 02:23 PM   #15
socalrider
Senior Member
 
socalrider's Avatar
 
Join Date: Mar 2004
Location: Upland, CA
Bikes: Litespeed Liege, Motorola Team Issue Eddy Mercxk, Surly Crosscheck Cyclocross bike, Fisher Supercaliber Mtn. Bike
Posts: 5,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
yes you can overinflate by 10 psi easily.. Stop buying 60.00 tires that fail.. Been using Vittoria rubinos - wire bead models - spec'd to 145 psi, I usually inflate to 130psi with zero issues.. 46.00 for pair of tires.. I buy mine here

http://www.ebay.com/sch/m.html?_nkw=...=bellsbikeshop
socalrider is offline   Reply With Quote
Old 03-05-12, 02:29 PM   #16
magohn
Senior Member
Thread Starter
 
magohn's Avatar
 
Join Date: Jul 2005
Location: Woodinville, WA
Bikes:
Posts: 1,503
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Mr B - me too. As my Roubaix is all Specialized and the original tires were awesome, Ive been trying to chase that reliability. Perhaps they have changed their build process. All I know is once could be a fluke but twice is a pattern. Time to change.

freight - Ive viewed your downhill descents . Your a braver person than me going at 30mph on a tire that could "blow". Mine was instant on both occasions. One second it was fine, the next a terrific bang (that really shakes you up) and the whole back-end wobble as the rim hits the road.

I blame myself though - I should have "searched" on the tire before assuming brand and price equals quality!
magohn is offline   Reply With Quote
Old 03-05-12, 02:46 PM   #17
ThermionicScott 
Gratuitous glib and snark
 
ThermionicScott's Avatar
 
Join Date: Aug 2011
Location: CID
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers)
Posts: 13,597
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 206 Post(s)
Could it be your mounting technique? It looks like the tube might have gotten pinched between the tire and rim, and dislodged the layer of tire fabric that contacts the rim when it blew.

Try using a size smaller tube and inflating it a couple psi before stuffing it into the tire.
__________________
Quote:
Originally Posted by chandltp View Post
There's no such thing as too far.. just lack of time
RUSA #7498
ThermionicScott is offline   Reply With Quote
Old 03-05-12, 02:56 PM   #18
Mr Sinister
Am I evil? I am Man!!!
 
Mr Sinister's Avatar
 
Join Date: Feb 2011
Location: Mass.
Bikes:
Posts: 448
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by TrojanHorse View Post
What kind of tires were you using?

I have Michelin Pro3 tires that are rated to 115 psi and I inflate them to 115 psi every time I go for a ride. I did blow out a sidewall one time (tiny little pinhole, not really a blowout) but I think that may have been related to a little incident I had on some jagged cement a week earlier. Anyway, the Michelins are apparently slightly infamous for blowing out sidewalls.

Hitting a sharp edged road hazard with any force is always a bad idea and can certainly result in the kind of issues you're facing.

Other than that, no tire blowouts of any kind up to 240#.
Just what I wanted to read... I bought a pair of these over the fall, and have changed my tires out to them.
Mr Sinister is offline   Reply With Quote
Old 03-05-12, 03:03 PM   #19
cohophysh
fishologist
 
cohophysh's Avatar
 
Join Date: May 2006
Location: Pacific Northwest
Bikes: Diamondback MTB; Leader 736R
Posts: 1,201
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
OP,
I am a little heavier than you and am on 25's and I inflate them to about 100psi. I have Bontrangers and so far no problems.
__________________
We cannot solve problems with the same level of consciousness that created them. A.E.

1990 Diamond Back MTB
2007 Leader 736R
www.cohocyclist.blogspot.com
http://www.loopd.com/members/cohocyclist/Default.aspx


cohophysh is offline   Reply With Quote
Old 03-05-12, 03:03 PM   #20
prathmann
Senior Member
 
Join Date: Nov 2008
Location: Bay Area, Calif.
Bikes:
Posts: 6,137
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 107 Post(s)
The pressure inside the tire will not be affected more than a tiny, insignificant amount by even the heaviest rider sitting on the bike or when impacting a pothole or other bump. Tire pressure is inversely proportional to the total air volume inside the tube (PV=nRT). When you sit on the bike there'll be a very small decrease in the volume right at the contact patch area - but this is a tiny portion of the total air volume in the whole tire so the pressure increase is insignificant.

Based on the picture, that looks like a defective tire unless the sidewall was cut in some way (such as by a brake pad mounted too high or a sharp object on the road that scratched the sidewall). Unless you're racing and at a level where the difference of a few seconds will be important then I see no reason to go with expensive tires. I haven't had any better experience wrt durability and reliability with $60+ tires as compared to ones that I buy for less than $10.
prathmann is online now   Reply With Quote
Old 03-05-12, 03:16 PM   #21
snowman40
Senior Member
 
snowman40's Avatar
 
Join Date: Feb 2009
Location: Orange County, CA
Bikes: Fuji
Posts: 1,144
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Vittoria. Recommended pressure >100 psi right there on the sidewall...

I ride between 110 and 120, I inflate to 120.
snowman40 is offline   Reply With Quote
Old 03-05-12, 03:21 PM   #22
volosong 
Senior Member
 
volosong's Avatar
 
Join Date: Apr 2011
Location: Antelope Valley, SoCal
Bikes:
Posts: 2,718
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by cohophysh View Post
...am on 25's and I inflate them to about 100psi. I have Bontrangers and so far no problems.
Same here. The 25's made all the difference in ride comfort. Max pressure on those tires are 100 psi. When I ran 23's, I also maxed out at 120 psi.
__________________
Deut 6:5

---

"Ha ha! You fool! You fell victim to one of the classic blunders - The most famous of which is 'never get involved in a land war in Asia'".
- Vizzini during his "battle of wits" with the Man in Black
volosong is offline   Reply With Quote
Old 03-05-12, 03:28 PM   #23
tergal
Senior Member
 
tergal's Avatar
 
Join Date: Nov 2011
Location: Logan, QLD ,Australia
Bikes: Trek 4300
Posts: 790
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
just a thought, are you sure your tyre pump pressure gauge is not screwy ? maybe it says 115 when really it is 125.

do you have a separate one you can confirm with ?
tergal is offline   Reply With Quote
Old 03-05-12, 04:31 PM   #24
Myosmith
Lover of Old Chrome Moly
 
Myosmith's Avatar
 
Join Date: May 2011
Location: NW Minnesota
Bikes:
Posts: 2,548
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I run my Bontrager H2 Ecos (700 x 28) at their rated 85 psi or even a couple pounds high when I'm riding exclusively on pavement. My Specialized All Conditions run at their rated 120 psi.
Myosmith is offline   Reply With Quote
Old 03-05-12, 06:07 PM   #25
TrojanHorse 
SuperGimp
 
TrojanHorse's Avatar
 
Join Date: Mar 2010
Location: Whittier, CA
Bikes: Specialized Roubaix
Posts: 11,237
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 115 Post(s)
Quote:
Originally Posted by Mr Sinister View Post
Just what I wanted to read... I bought a pair of these over the fall, and have changed my tires out to them.
Don't get my wrong, my pair have been great, comfy and grippy - no complaints! The issue I had was a direct result (I think) of a little riding stunt I did to get around my kids when they cut in front of me. I only buy them when they're on sale for $45 or less anyway.

I was booking down a hill yesterday at about 45 mph and not worried at all about the tires. Since I just put the bike together about a week and a bit ago, I was PLENTY worried that maybe I didn't screw something on right.
TrojanHorse is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 12:21 AM.