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  #1  
Old 08-05-2021, 03:51 PM
PandaCub PandaCub is offline
 
Join Date: Jul 2019
Location: Colorado Front Range
Posts: 25
Default Curious Flat Tire on my RV-14A

Well this a new one (to me, anyway):

After several months with no tire trouble, no hard landings, etc I made an uneventful landing at Bloomington, Indiana. After refueling and taking a 20-minute break at the FBO, I came out to discover my left main was flat.

The folks at KBMG were exemplary and jumped into action to help me solve the problem. We ultimately discovered the flat wasn't from a puncture or leaky valve stem but from a small rupture at the tube's sidewall - in an area roughly same shape as the tire rating stamp that's embossed onto the tire (see photos).

Anyone else ever have this happen? I'm still scratching my head.





Can't see images myself, so here are links:

https://imgur.com/a/tle7rQH

https://ibb.co/Gt9HP1h
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Carbon Cub FX-3 CCX-2000 (N134PB)

Last edited by PandaCub : 08-05-2021 at 04:01 PM. Reason: Images not appearing
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  #2  
Old 08-05-2021, 05:01 PM
Ron B. Ron B. is offline
 
Join Date: Nov 2007
Location: Yarmouth, Nova Scotia
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Do you know if you used talc powder when the tube was installed? We had a similar re-occurring problem on the front tire on our Amph floats. Were trying different tire pressure, different tubes until someone asked if we were using talc. I hadn't heard of it but once we applied the talc on the new tube , never had a flat since. The tube didn't have the shape yours do but it was from the tire rubbings on the tube.
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  #3  
Old 08-05-2021, 07:39 PM
Christopher Murphy Christopher Murphy is offline
 
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Location: colorado
Posts: 932
Default Yep..

No or not enough talc or running excessively low pressure.
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  #4  
Old 08-05-2021, 07:45 PM
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rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
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Wear spot caused by tube movement against the interior surface of the tire.

As mentioned, caused by too low of air pressure, not enough talc, or a combination of the two.

When I install tires I coat the entire inside of the tire, and I apply a coating to the tube before inserting it in the tire.
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  #5  
Old 08-05-2021, 08:36 PM
Jake14 Jake14 is offline
 
Join Date: May 2014
Location: Seattle
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Interesting...maybe the effect of stamping the sidewall (making it thinner and less rigid) caused the tire and tube to bulge in that region and present a ridge against which to rub....

maybe the manufacturer should be informed....
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  #6  
Old 08-06-2021, 05:29 AM
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rv8ch rv8ch is offline
 
Join Date: Feb 2005
Location: LSGY
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Good to know that can happen. What kind of tire and tube? I've been using talc since my motorcycle days in the 70s more out of habit than anything else, and I've never seen a tire rub through a tube. Is there perhaps a manufacturing defect inside the tire?
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  #7  
Old 08-06-2021, 09:43 AM
Ralph Inkster Ralph Inkster is offline
 
Join Date: Feb 2008
Location: Calgary, Alberta
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Years ago I had a recurring nose tire (Lamb) going flat for no apparent reason. Kept replacing tube and suffering same result. I finally took a close look inside the tire & found a series of barely detectable rubber injection nubs in the sidewall (similar to the ones you find on the treads of some tires). Dremel tool used to smooth them out and never had problem again. & yes, Talc powder is a must.
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  #8  
Old 08-06-2021, 09:56 AM
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wcalvert wcalvert is offline
 
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Back in my "road bike" days (bicycle), we would Talc our bottoms to prevent chaffing in the saddle area ...

That same can of talc came out for any tube patching, lots of talc inside the tire and on the tube made everything go together easier and prevented those pesky pinches that would flat a tire in a second.

Old habits die hard (I don't talc my bottom any more) but I sure do talc any tube I install !!!
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  #9  
Old 08-07-2021, 07:24 AM
PandaCub PandaCub is offline
 
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Location: Colorado Front Range
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Thanks for the insights, gents. I've ordered new Michelin tubes and tires - and a large can of talcum powder!

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  #10  
Old 08-07-2021, 09:17 AM
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plehrke plehrke is offline
 
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Location: Defiance, MO
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Quote:
Originally Posted by wcalvert View Post
That same can of talc came out for any tube patching, lots of talc inside the tire and on the tube made everything go together easier and prevented those pesky pinches that would flat a tire in a second.
Plus my tires smell baby fresh as I am using up the talc powder my wife no longer is allowed to use.
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