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Firecrackerktm

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Discussion starter · #1 ·
I keep getting flats ... but only when going downhill. This is the third one now.

I haven't found any thorns or glass or anything in my tires, and the tubes seem to hold air later (haven't put them back in, but filled them up in the garage to see). Could it possibly be something to do with my brakes getting hot?
 
Discussion starter · #4 ·
No patches, and like it says I didn't put the flatted tubes back in the bike. I just aired them back up when I got home to see what would happen, and left them in the garage. They aren't leaking now.

how much more air? 45 psi now.
 
#5 ·
With the tube pumped up put it in a bucket of water and see if there is air leaking out. This will help you find where you are getting the flat. I doubt you are getting pinch flats at 45 psi. Also, check the inside of the tire. Turn it insideout and run your hand around to make sure there isn't anything in there. Check the rim tape, make sure there isn't a spoke poking the tube. Check the seam of the rim and make sure it doesn't have a rough spot on it. Finally check the valve stems.

Of course when you find the hole in the tube, it will give you a clue as to why it keeps going flat.
 
#10 ·
Firecrackerktm said:
And why does it only happen when I'm going downhill?
Click to expand...
either strange coincidence or because you are going faster and hitting rocks harder which would make pinch flats more likely

Flats are basically always either a puncture (thorn, glass, etc) or a "pinch flat" as pop_martian explained where you hit a rock hard enough to cut the tube. If you can figure out which one is your problem then you can figure out how to fix it. A puncture will generally be only one hole and possibly very small. A pinch flat will usually be two parallel cuts that are at least 1/8" long. If you have trouble finding the holes, inflate the tube and hold it under water to see the leak.
 
Discussion starter · #14 ·
Yes.

And all 3 times I was riding along, lalalala, and all of a sudden I could hear a hissssss of the tire flattening.

I bought Specialized tubes this time. Maybe they will be better.

I am wondering about the thorn resistant style. Are they worth the weight sacrifice? if they weigh a little more but dont' go flat, I'd be OK with that.
 
#15 ·
Firecrackerktm said:
Yes.

And all 3 times I was riding along, lalalala, and all of a sudden I could hear a hissssss of the tire flattening.

I bought Specialized tubes this time. Maybe they will be better.

I am wondering about the thorn resistant style. Are they worth the weight sacrifice? if they weigh a little more but dont' go flat, I'd be OK with that.
Click to expand...
Did you investigate your old tubes yet? You can't find the proper solution until you know whether it is thorns or just pinch flats. They are two very different things
 
#17 ·
Firecrackerktm said:
No, hubby cleaned up the garage and threw them away :( I didn't tell him I was going to see what was wrong with them.

I did check the rim & spokes, and that all seemed OK.
Click to expand...
Oh well. Hopefully it never happens again and you won't have to worry about it, right:thumbsup:
 
#18 ·
This doesn't make sense...

Firecrackerktm said:
Yes.

And all 3 times I was riding along, lalalala, and all of a sudden I could hear a hissssss of the tire flattening.

I bought Specialized tubes this time. Maybe they will be better.

I am wondering about the thorn resistant style. Are they worth the weight sacrifice? if they weigh a little more but dont' go flat, I'd be OK with that.
Click to expand...
So you were riding along with the valve in the closed position, you hear air leaking out of your tube, it quickly goes flat but when you get home and pump up the flat tube, it holds air?
 
#20 ·
I posted up somewhere here, that I always had flats, somethime twice on a ride.
my current bike came with WTB Weirwolf 2.3, no flats fron thorns or pinched flats at any pressure, 25 to 45 psi. It's been over 2 years.
The Weirwolf have thick sidewall that protect from side impact punctures and flats. they also climb, and descend well. and so far are good in the wet and sand.

you might want to go to a tire with stronger sidewalls.
 
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