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Frequent flatting help?!?(10 posts)

Frequent flatting help?!?BigEye
Aug 15, 2002 2:37 PM
Hey, everyone - hoping for some insight here -

I've been back on a bike for the last 6 months - bought a Jamis Coda which
I'm really happy with. But I keep getting flats. With my knobby tire bike of
years ago I never did, so I don't have a feel for why.

I am riding on Avocet cross k 700X32 with tire liners.
Specialized tubes.
I have checked the rimstrips and they seem fine and in place.

I am mostly riding paved roads, very little curb hopping.

When I put the tubes in, I check to make sure they are not caught between
the tire and the rim. I roll the tires between my fingers to help seat the tubes well up
into the tire.

I fill the tubes up, then deflate, then reinflate to help with the seating
(suggestion from my bike shop guy).

I am on my second slow leak in two days. Any ideas, tips, tricks?

Are the tire liners too much with the stiffness of the kevlar beaded cross k's?

Anything? Anyone? Very frustrating.

Thanks in advance!
First thing to do. Analyze the problem.Spoke Wrench
Aug 15, 2002 2:44 PM
Where are the holes in the inner tubes? Inner or outer circumference? Is it the same place relative to your tire? Is it the same place relative to your tire liner?

Answer these questions and you won't have to ask me what to do next.
Spoke's right, but a couple of suggestionsSilverback
Aug 15, 2002 2:55 PM
Once you see where the holes are, you'll be on the way to fixing the problem. I've the flat king of the western U.S., though, and I have a couple of possibilities:
Your tires are plenty stout for the road--many people would say they're too heavy. For that reason, I'd guess that IF tires are the problem, it's a thorn or something stuck in the rubber, not a new sharp thing every time. Run your fingers or a piece of cheesecloth (snags on the point) around the inside of the tire very carefully. Also check the tire liner--I've seen thorns break off in those so the point just protrudes enough to flat the tube over time.
If the punctures are on the rim side of the tube, examine your rim strip. You don't have to have the end of a spoke sticking out to cause trouble--just a tiny slice of the spoke HOLE, if it's exposed, will let a little of the tube slip in and wear a hole in it.
First thing to do. Analyze the problem.BigEye
Aug 15, 2002 3:11 PM
Well, the weird part is, when I changed the tube out this AM I couldn't find a freakin hole! I put some air in, dunked it in water, and still couldn't find it. So I thought, well, either it's really small, or maybe somehow I messed up the valve, so I put another tube in and did my ride-to-work. But after being at work for 5 hours, my tire is noticably low in pressure, just like it was before I replaced the tube this am. So I dunno where the holes are. I just deflated and reinflated it again and we'll see what happens when I leave.

Keep those thoughts comin'!

Aug 15, 2002 4:33 PM
Did you fill it with CO2 is permeates the rubber and goes flat in a day or 2
Or latex tubes ...Humma Hah
Aug 15, 2002 4:35 PM
I don't hear about those in roadbiking so much, but some MTB racers use em, and they ooze air fairly quickly.
Slow leaks, huh? Try this ...Humma Hah
Aug 15, 2002 4:33 PM
Run your fingers or a piece of tissue around the inside of the tube and the inner surface of the rim. Chances are very good there's a small piece of glass, wire, or maybe a little sharp metal edge sticking out just far enough to ding your tube.
Aug 15, 2002 8:08 PM
had a piece of glass stuck in tire and it would give me a flat once in a while only when I'd hit something at that spot. My second guess would be rimtape if it shifted and or has punctures. Third which tubes? some are pretty crappy.

try to find a leak, if it is on inner side it's gotta be rim tape if out either a liner or what Humma says.


PS also check the valve good luck
re: Frequent flatting help?!?cabinfever
Aug 16, 2002 3:46 AM
1. As stated, check for glass/thorns in tire.
2. Use a quality rim strip. I find I can only use a Velox or Pedros rim strip. The plastic ones seem to shift. Others may have suggestions, but these have always worked great for me.
3. Check your rim. I've notices some rims have a burr on the inside. Especially at the joint where it is welded together. They grind the rim side wall smooth on the outside, but often leave the weld rough on the inside. You might need to file off some. With a slow leak, this doesn't sound like your problem, but I thought I'd throw it out there.
OK, try this:Spoke Wrench
Aug 16, 2002 5:11 AM
When you get home, blow up one of your defective tubes really big. Then try the water thing again and see if you can find anything. Use the bath tub. If it will fit in the toilet you havn't inflated the tube enough. Good luck.

It's not the tubes. I suppose it's possible for a manufacture to have a bad run of tubes. It's also possible to hit the lottery. I put the odds about equal.

With those tires plus the tire liners, I think we can eliminate the possibility of a new thorn or piece of glass every day. I'd also set aside for now the notion that you have a persistant thorn or piece of glass sticking in your tire because you are also running the tire liner.

What tire liner? Mr. Tuffy's have a history of causing flats themselves where they overlap, but it usually takes way more than a ride or two to abrade the tube enough to cause a leak so I don't think that's it either.

That leaves the rim as the most likely suspect. The rim tape needs to go all of the way from flange to flange. Does it? The tinyest little crescent of spoke hole showing will cause repeated flats every single time. One of my biggest aggrivations with MANY bike manufacturers is the crummy rim strips they use. Check the inside of the rim, especially under the flange where it's joined to see if they left a burr when they cut the extrusion.

Once you are sure the rim and rim tape are OK, it's time to revisit the persistant thorn theory. Sometimes you just have to buy a new tire. I had a piece of glass in the Continental Double Fighter on my beater bike that I never could find. After a few flats I replaced the tire and havn't had a puncture since.