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Too Many Flats - What am I doing wrong?(14 posts)

Too Many Flats - What am I doing wrong?waterman
Jun 7, 2001 6:43 PM
I have gone through 4 tubes in the last 3 weeks

Flat 1 - Front Tire - Hole in "rim dimple" area
Flat 2 - Front Tire - Hole in "rim dimple" area
Flat 3 - Rear - Valve Stem messed up - would release air when you pushed the valve stem to the side
Flat 4 - Reat Blowout - 1.5" hole down the side of the tube

I weigh 230 so I am a bit heavy and run 120 PSI in the tires.

The bike is a 2000 Allez Comp with Mavic CXP 23 wheels.

I go for 30-40 minute rides 3-4 times a week.

I do live in Arizona so it is 100-110 degrees when I am riding.

I have been using Specialized tubes.

Any suggestions on the source of the problem?
Is it normal to have bad streaks?

When my rear tire blew out today, the rim was bent a little bit. Should the shop fix the rim under warranty (bike is 9 months old) or is the repair on my dime?

Thank you
re: Too Many Flats - What am I doing wrong?Canidraftyou
Jun 7, 2001 6:57 PM
Sorry to hear that luck, try this one. I run Axial Pro's, im one my third set since the first of the year. Thats $300 to date, im running 110 lbs to 115 lbs. im 190 lbs. Heck, I love how they roll so I pay the price.

Peace out

re: Too Many Flats - What am I doing wrong?carbon man
Jun 7, 2001 7:01 PM
I have been running Axial Pro's for the last 4 months with over 1000 miles on them and no flats yet.
re: Too Many Flats - What am I doing wrong?Cliff Oates
Jun 8, 2001 1:15 PM
FWIW, I've got 1600 miles on a set of AP's and they're going strong with only one pinch flat roughly 500 miles ago. I've been using a Specialized thorn resistant tube since I had that flat in my back tire. I also weigh 190 pounds and I run the tires at 120 PSI. The back tire has a few hundred miles left in it, and I suspect I will want to buy a few more of those tubes.
rimstrips, tire size...C-40
Jun 7, 2001 7:04 PM
At your weight you should probably be using 700 x 25 tires. If I understand the front flat problem (holes on the underside of the tube, near the rim) this is caused by bad rims strips. Get some Velox rims strips made of heavy, adhesive backed fabric.

The valve stem problem could be from sharp edges around the valve stem hole.

A tube blowout often occurs when the tire's bead isn't properly seated on the rim. A small area of the bead breaks loose from the hooked edge of the clincher rim, the tube squirts out the side, and blows out, instantly.

After installing a tire, inflate to only about 30-40 psi and roll it along the floor, while pushing down hard, to help seat the bead. Then inflate to about 80-90 psi and let the tire set awhile, before inflating to full pressure.

Your tire pump could also have a faulty gauge. If you're putting in 130 psi, instead of 120, you're more likely to blow a tire off the rim.

I recommend Continental Gran Prix tires, in 700 x 25. They are reasonably light, and long wearing.

The rim problem is on you. Tough luck, but that's what can happen if a tire comes unseated from the rim.

Lastly, lose some weight!
Was that last cheap shot really necessary, C-40?boy nigel
Jun 8, 2001 10:54 PM
Seriously. The guy SAID he was a bit heavy; he's aware of his weight, and he's riding to get fit and lose some. Give the man a break, for Christ's sake. After taking some time and giving some fairly sound advice, you sh*t the bed at the end--and with an exclamation point! What's that all about? Your C-40's gone to your head? If you meant it as a joke (poor sense of humor), you must realize that it won't be taken as such without proper text (i.e., "Just kidding") or signage (e.g., a smiley face). Etiquette is important; learn it.

While I'm at it, the Velox products you're referring to are "rim strips," not "rims strips."

get a sense of humor when you grow up, Boy (nm)C-40
Jun 9, 2001 8:10 PM
Think up something funny, phrase it right, and I'll laugh at it.boy nigel
Jun 10, 2001 10:37 PM
I'm not looking to fight with anyone here. I felt that your last bit was insensitive. When READ online, there's no way to figure that you're joking. If I wrote, "Don't worry, C-40, you've got a fat ass anyway," would you take it as a joke? You wouldn't really know HOW to take it, would you? There's simply no way to get the real picture with an "unfunny joke" like you wrote without including something like a :) or a ;) or a :P after it. If you don't like these "faces," and are above writing "Just kidding," then you don't like communicating properly on the Net.

You may've meant it as a joke; if so, that's fine. People can be sensitive about their weight, and to some out there it's no laughing matter. I'm cool with it, but I wouldn't make a joke like that unless I was sure it'd be taken in the proper way.

Don't be afraid to learn something, C-40; you're only human.

re: Too Many Flats - What am I doing wrong?girl
Jun 7, 2001 7:08 PM
Did you find any glass/foreign objects in any of these flats? If so, did you check the inside of your tire for anything stuck in it? Sometimes glass can imbed itself in the tire, so if you fix your flat and start riding again, the imbedded glass can pierce your tube again. Your rear flat could easily have been a pinch flat, which happens (you probably know, I'm just yakking) when you, for instance, hit a pothole or a bump and don't have enough air in your tube. How bent was your rim? Are we talking seriously bent, or just a little out of true? And this is probably a really stupid question, but are you sure your tube is seated properly in the rim? (It's not bunched up or anything...) You should check for bulges in the sidewall of the tires after you re-inflate. Have you been patching your tubes properly? (Waiting a proper amount for the patch to dry...I can imagine in 110 degree heat that could be a problem)
And yes, everyone goes through good and bad runs of luck with flats...sometimes you get 3 a week, sometimes you badly need new tires and won't get a flat for months!

I'm no technical genius...just some common sense advice.
Couple of ideas.Spoke Wrench
Jun 7, 2001 7:09 PM
When you say "rim dimple" area are you refering to the spoke holes? If so, I'd say you have a rim strip that has exposed a part of the spoke hole. When this happens, repeated flats are the result. The solution is to install Velox rim strips that are wide enough to span the entire area between the two rim flanges.

Tube cuts at the base of the valve stem are often the result of screwing those little valve stem nuts too tight. When this happens the tire tries to flex when you take a hard turn and the valve stem doesn't, Consequently the valve stem tears at its base. Personally, I think those little valve stem nuts are the work of the devil and I don't use them on my own bikes.

Warranties cover "manufacturers' defects." If your rim had such a defect that caused your tire to blow out, it would be a warranty item. Most likely, however, the rim bent as a result of the blow out. If that's the case, you're out of luck.
re: Too Many Flats - What am I doing wrong?DINOSAUR
Jun 7, 2001 7:15 PM
Pull off your tires, tubes and rim tape. Carefully run your fingers around the inside of your rim. You have something on the inside your rim that is causing rim punctures. Sand the inside of your rims with a lightly graded peice of metal sandpaper. Make sure that you clean your rims carefully and remove all the remains of the metal shavings. The main cause of rim punctures is under inflation. What is the recommended pressure for your tires? Inflat them to that pressure. I use Michelen A-1 airstops and have had good luck. Each time you replace a tire, replace the rim tape also. It could very well be that your rims don't even have rim tape, some manufacturers substitute cheap rubber strips that don't work worth beans. You should have the rim replaced, unfortunately it will most likely be on your dime. One more thing, run with 700X25 tires. I've had good luck with Conti GP 3000's. I know this sounds like a hassle, but it will take about an hour or so. Good luck, let me know if this works...
re: Too Many Flats - What am I doing wrong?waterman
Jun 7, 2001 9:30 PM

All of you have been very helpful!

I do NOT have any rim tape in my tires. I have seen places that sold rim tape and wondered why my bike did not come with rim tape. I guess specialized saved $.35 by not putting rim tape on my bike. Rim tape will prevent the front flats I was getting.

I am running 700X23 tires - It makes sense that I would need a set of "fat boy" tires. Where could I find a set of the Continental 3000's in 700X25? I checked a few places and they only list 700X23.
re: Too Many Flats - What am I doing wrong?Lou M
Jun 8, 2001 6:40 AM
I recently got back into riding and my weight was a concern initially. I had ballooned to 245 (6'1") and was concered about tire pressure and flats. I have been riding Conti GP 3000's on Campy Shamal wheels @ 125psi. I check the tire pressure every 2-3 days to make sure that I have at least 120psi. I haven't had one flat yet and I average about 150miles per week.

Good Luck and keep riding hard (I am down to 225!! and counting).
re: Too Many Flats - What am I doing wrong?mackgoo
Jun 8, 2001 9:56 AM
Pump your tires up every day before the ride, maybe a little higher than what you are running now. Go to the max pressure on your tire and obviously try not to drive over anything that really "thuds" the tire.