My road bike sat in the same spot over the winter and, as expected, the tire went flat. When I filled the tires and went for a ride the back tire feels like it has a flat spot. The tire was relatively new. Is it possible to get a permanent flat spot letting it sit like that? It never happened before and I’ve had this bike for more than 30 years.
I’ve had car tires develop flat spots like that, though usually it’s because the car sat for a lot longer than a few months. Driving the car around for a week or two usually worked out the flat spot and the tire went back to normal.
I wouldn’t be so eager to try that on a bike. If you are getting a lot of tire vibration going around a turn, you can lose traction a lot more easily. But, if you are careful, you might be able to work out the flat spot.
My bikes lose a little bit of air over the winter, but nowhere near enough to go flat and develop flat spots (and they aren’t new bikes - both about 25 years old, but they are well-maintained). You probably have a slow leak in the tire or the valve stem or maybe some rust on the rim that is preventing a good seal.
Are these spoked rims? I’ve seen a lot of spoked rims develop rust around the spokes.
ETA: I was assuming bike = motorcycle, but on re-reading this I see that it could mean bicycle (same terminology could apply to either). Either way, it’s the same basic advice. You shouldn’t be losing that much air over the winter, and you can work the flat spot out of the tire by riding on it.
Its a bicycle and these types of tires do slowly leak out over time. I have to put air in them every few days to maintain high pressure (10lbs). There’s no wobble just a thump on every revolution. The spot seems to be at/near the valve stem, FWIW.
tire may also not be seated on bead or tube pinched
I suppose though that the tire could have deformed, though bicycle tires are very light and flexible
Best to hang bikes when not in use
I presume that was a typo? Unless you meant “per square centimeter” or something.
Yeah, my road bike tires take about 120 lbs.
Did you check the tube inside the tire? Those inner tubes are a lot more fragile than tires and possibly more sensitive to winter freeze/thaws. Fortunately they are also cheaper to replace, <$5 and any bike shop can teach you how to do it.
The tires maybe “cupped” which can handle on any tire that has deflated and then not rotated.
The sure fire way to solve this is new tires, but I take it you want to keep them or try something to fix it.
I can only offer my non-scientific/hope this works “advice” from my days as a bicycle mechanic. Which would be to deflate them to 100 PSI or so and leave them in the sun, hoping they’ll get warm enough and with the pressure to restore their shape. You can also try and take the tire off and kneed the sidewall with your thumbs to take the deformation out.
A way to tell if it’s going to be more or less permanent is to take the tire off the rim and lay it flat. If the deformation is still there, it probably won’t go away. Also depends on the sidewall type and construction.
Looking at your last sentence, perhaps if the tire deflated during prolonged un-use, the tube could have moved and the tire may have unseated from the rim. If the valve stem is not seated properly within the tire, you may be experiencing a bump and not a flat spot. To address this, deflate the tube and ensure the tire is seated properly in the rim, and the valve stem is pushed up into the tire before inflating.
Your tire is probably not seated on the rim evenly.
When I change a tire, or if it has been flat, I pump the tire up to max. Then I spin the wheel on the bike and watch for high or low spots. If it does not appear to be spinning true, (just the tire, not the wheel), I let most of the air out and pat the tire all the way around with my palm to try to reseat it. I then refill the tire and check for trueness again.
I’ve heard people really geek out about proper bicycle tire storage before - but if your tire really did develop a flat spot from sitting all winter it would be the first time I’ve known someone to actually have a noticeable negative impact from improper tire storage.
Probably it’s not seated right.
The valve stem should not just be pushed up into the tire; it should be pushed up and pulled back out to make sure it can move freely when the tube is slightly inflated.
Heat also has an effect on tires - like if was leaning against a radiator or something. Once I had tires hanging too close to a light bulb and it ruined them. They were nice tires too - gatorskins.
I think all the advice you’ve received is bang on.
The only thing I would add is regarding your need add air every few days: I had a similar situation two years ago. I was losing about 5 to10 PSI daily. I assumed it was a leaking valve or tiny puncture, but an avid cyclist friend told me that my 2 year old tubes were failing. She said the tube material breaks down as it ages and oxidizes and becomes increasingly porous over time allowing the air to migrate through it.
I ended up getting these German Schwalbe brand tubes::
http://www.chainreactioncycles.com/sg/en/schwalbe-road-tube/rp-prod26727
They supposedly have some proprietary rubber blend that keeps them air tight longer.
I’m almost 2 years into these and I’m very happy. I top up about 5 PSI every couple months.
Losing 5-10 psi in a day is totally normal for road bike tires rated for 120 psi. The rate of loss is highest in that first day, and in the case of my bikes usually doesn’t drop lower than 80 psi which can take weeks. This is with clincher tires and inner tubes, not tubeless or tubular.
Maybe this is “normal” for a 120psi road bike tire, but not for me. Based on my experience, the advice I was given was 100% accurate.
I ride a hybrid running at 90PSI and doing 300 to 500km/month fitness riding at 20 to 22kmh. I went from 5 to 10 PSI loss per day to 5 to 10 per two months with the new tubes. I’m holding at that deflation level so far after 2 years.