So last summer I bought my first Power Tap with Renyolds Assault carbon wheels. Those wheels have a 21.6mm rim width. Since putting those wheels on I have gotten more flats in one season then in the 5 years I have been biking. Mostly in the back tire but also one in the front. I have examined the wheels and was very careful when installing a new tube, had the bike mechanic check, got nothing. I am signed up for my first IMMT in August and am nervous that I will flat (maybe more than once) during the race. Anyway, I started thinking that maybe I will get the new FLO 60 wheels and read up on them. As part of their online description they sited as an advantage of their wider rim (24.6mm I think) a reduced pinch flats. Being that I am worried about my excessive flatting I am thinking of racing with the FLOs and not having power and hopefully less flatting. So back to my question, how likely is a smaller rim be more prone to pinch flats compared with a 24.6. My tires are the continental 4000 II 23 mm. Thanks.
you didn’t mention if they were actually pinch flats you were getting.
double check the rim tape you are using, some of the cheaper ones are crap (stretch when the tire is inflated, which exposes the spoke holes).
checked and rechecked. Would pricey Renyolds Assault carbon wheels come with cheap tape? Whats the best tape I can try?
velox.
you didn’t mention if they were actually pinch flats you were getting.
double check the rim tape you are using, some of the cheaper ones are crap (stretch when the tire is inflated, which exposes the spoke holes).
Yes, check for the classic snakebite on the tube and realize that a pinch flat will occur immediately after hitting a serious hole. You can usually feel the rim actually hitting solidly against the ground. If the snakebite is not there than you probably aren’t pinch flating.
Whatever you do, make sure you spend the time to figure out where the leak is. Something as simple as a bur in the valve stem hole could be causing you problems.
A wider rim isn’t going to prevent many pinch flats unless you put a really skinny tire on there. You will be more likely to break a wheel though .
Wider rims are slightly less prone to pinch flats, but tire pressure is usually the main culprit (and of course an impact).
As others have mentioned, be sure it’s actually pinch flats (look for the snakebite puncture holes). Where and what type of holes are a good clue to the root cause.
Common causes:
Hole on the outside of the tube: Glass or metal lodged in the tire casing.
Hole near the stem: Possible burr in the valve hole.
Hole on the underside of the tube: Exposed spoke hole due to shifting or poorly applied rim tape.
Two holes on the side of the tube: Snakebite (increase tire pressure).
Leak at the valve stem: Poorly made tube where the metal stem has pulled away from the rubber.
A couple of times i threw out the tube wo checking. A couple of times i did check it was pinch (2 holes close together). The tape looks good but i cant tell if its shifting or not.
21.6mm rim width is not narrow relatively speaking. And certainly isn’t narrow compared to the rims everyone was using 5+ years ago.
You have another issue entirely.
I am certain it is possible to get a pinch flat with only one hole in the tube.
I am certain it is possible to get a pinch flat with only one hole in the tube.
It is possible, one side may cut through, while the other side of the “pinch” does not. Most cases you get the double sided one though.
Another teletale sign is the the holes look like a cut vs. a hole. The pic below is a classic pinch flat.
http://2.bp.blogspot.com/-Mu_snGTo_VQ/Ty4H8QLIiOI/AAAAAAAAAs4/DOQxuD8mJAs/s320/image004.jpg
In this pic, the hole on the right is a single-side pinch flat. The one on the left is a puncture flat.
http://i105.photobucket.com/albums/m204/Todd_ME/bike%20repair/BikeRepairsOctober162006003.jpg
One surefire cure for pinch flats is to go with road tubeless…alas not an option for carbon clinchers.
for the past 2 years I’ve had a set of Reynolds Assaults on firstly mt QR and now my P3.
and I don’t want to put a hex on myself, but am still to have my first flat.
at 100 kg ( 225lbs ) I’m no lightweight and the roads around my are of Sydney, Australia, are not known for their superior surface, just lots of chip seal & potholes. 23/25 tyres and other than wet days is 90 lbs Front, 100 lbs Rear.
check your rimtape and valve hole as suggested as well as ensuring the tyres are correctly inflated for every ride.
and if you’re really worried about it, replace the whole shebang, rimtape, tubes & tyres