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Flatlander
08-06-2006, 04:23 PM
My husband keeps getting flats, and I keep fixing them. I haven't minded much, since I want the practice fixing them quickly, in case I get one during a race. However, I am about to reach the point where it isn't fun to fix one every day.

The odd thing is that I do more mileage than he does. The only place he rides is to th gym or his office on campus. I ride these same routes just as often and never get flats.

He has brand new tires, at my suggestion, but that hasn't stopped the flats.

The punctures are almost always on the inside of the tube--the side next to the rim. I thought that maybe it was something to do with his rim, but today I was fixing one of his flats when he wanted to go to the gym so I took my wheel off my bike and put it on his. He rides it to the gym, comes back ouside and it is flat. So he walks his bike home and shows me the tire.

Mind you, this wheel had just gone 32 flat-free miles not more than a couple of hours ago, and a couple of hundred more miles previously, so I can't imagine that it is a pinch flat at this point. And, since he has now flatted on my rim, I don't think it is his tires or rims causing it.

I take it outside to work on it and happen to notice that his other tire is flat, too. That's 3 flats in one day, and he hasn't ridden the bike more than a mile.

What the heck is going on? Anyone have any suggetions about why he might be getting so many flats?

DebW
08-06-2006, 04:50 PM
The only way to track this down is to analyze every single flat and try to determine the cause of each. First obvious place to look is the rimstrips in his wheels, if the tubes are always punctured on the rim side. Even if they don't obviously look bad, replace them if they are old. Are the flats always the same distance away from the valve stem? Find that spot on the rim and look for metal burrs. The fact that your wheel flatted too could be a coincidence, but where was the puncture in your tube? What brand of tubes are you using? Some of the ultralight tubes are not very reliable. What size tires, what pressure, and how much does your husband weigh? If you are much lighter than he, you can get by with more than him in terms of pressure variations.

Or you could give up and get this guy solid rubber tires. :D

Flatlander
08-06-2006, 05:00 PM
The only way to track this down is to analyze every single flat and try to determine the cause of each. First obvious place to look is the rimstrips in his wheels, if the tubes are always punctured on the rim side. Even if they don't obviously look bad, replace them if they are old. Are the flats always the same distance away from the valve stem? Find that spot on the rim and look for metal burrs. The fact that your wheel flatted too could be a coincidence, but where was the puncture in your tube? What brand of tubes are you using? Some of the ultralight tubes are not very reliable. What size tires, what pressure, and how much does your husband weigh? If you are much lighter than he, you can get by with more than him in terms of pressure variations.

Or you could give up and get this guy solid rubber tires. :D

Hi Deb--He weighs about 60 lbs more than I. We discussed this as a possible reason, that perhaps the extra weight is somehow driving the tube up into the spoke hole. I keep the tires at the low end of the pressure recommendation (~100-110 psi). Should they be at the higher end for him? (He weighs 190.)

DebW
08-06-2006, 05:06 PM
He should be running more pressure than you. That probably doesn't explain constant flats, but could make them more likely. I'd change his rim strips and see if that helps.

Flatlander
08-06-2006, 05:09 PM
Thanks!

He has old wheels, so I'll change out the strips and add more pressure to see what happens. Hopefully,the flat on my wheel was a coincidence, but I'll check them, too, just to be sure.

tulip
08-06-2006, 06:24 PM
The best way to get flats is to run low pressure. Pump up those tires, and pump them up every day!

emily_in_nc
08-06-2006, 06:28 PM
I had a string of five flats in just a few weeks (after none ever for a year or so before that) a couple of summers ago. Turns out that when my husband put rim tape in my new wheels, it wasn't quite wide enough, so I guess some spokage was coming through. Once he put on wider tape, problem solved. I don't know if that's the problem here but glad you're going to change it out, just in case.

And yes, the more he weighs, the more tire pressure he needs to run to prevent pinch flats. But since you say that most of the punctures are on the rim side of the tube, I suspect something with the rim. Inspect it closely!

Good luck,
Emily

Flatlander
08-07-2006, 03:17 AM
Thanks, all! It sounds more and more like I need to change that rim tape and pump those tires to the max.

I'l hit the LBS this morning as soon as they open. :)

DebW
08-18-2006, 12:25 PM
Flatlander, is there an update to this story? Have the flats stopped, or are they still a daily occurrence?