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I ride a hybrid on 26" rims currently fitted with hybrid tires. As I am 300lbs+ the rear tire runs permanently deformed/flat and the rims ride over the rubber causing tire pinch. Can anyone recommend the tyre tube combination that I should try to obtain that will stop this happening?

  • 1
    What tyre pressure are you running? – Criggie May 10 '16 at 20:12
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    Would also be good to know the exact model and width of your current tyre – Andy P May 11 '16 at 8:09
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    It definitely sounds like your tire pressure is too low. You should be running AT LEAST 40 PSI with any tire, and generally closer to 65 with wider tires, 100 with narrower ones. What width tires are you using? – Daniel R Hicks May 11 '16 at 20:53
15

As a heavy rider personally, I don't have many issues with flats.

A normal tire on the high/maximum pressure works fine to avoid pinch flats.

The key is to check tire pressure every time you get on the bike. Even a day will allow a tire to soften 10 psi, and that will allow flats to occur.

Road hazard flats are not avoidable except by avoiding the hazard in the first place. :)

Edit: to be clear, my answer is that it is most likely that your existing tires are not fully inflated, rather than that a different tire is needed.

  • 4
    Getting a pump with a built-in pressure gauge will help immensely, as tires are typically grossly under-inflated without one. – altomnr May 10 '16 at 14:27
  • If you're losing 10psi in a day, are you running lightwieght tubes? Narrow tyres? I expect more like 10psi in a week on a 28mm tyre with (e.g.) standard tubes from continental. – Chris H May 10 '16 at 14:43
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    Actually, the first 3 days, with 25c tires, I drop from 125 to about 100psi with regular Conti tubes and GP4000s tires. I prefer tubbies, for that reason, but I'm in need of a new set of wheels for that at the moment. – zenbike May 10 '16 at 14:47
  • Its possible my weight adds to the pressure loss, though. – zenbike May 10 '16 at 15:13
  • If you hit a road hazard once a day by accident, you can easily lose 10 psi. – Batman May 10 '16 at 15:38
7

Do a web search for tandem tires. A tandem bike carries two people, so typical loads are even bigger than you.

Also, definitely use a pressure gauge. You may think you can tell by feel, but I ride every day and can't tell the difference between 80 and 100 psi.

  • Not really - tandem wheels tend to have more spokes, and sometimes thicker gauge spokes, and better rims, but the tyres and tubes are just normal 700c . They do tend to be wider though - 28 would be narrow for a tandem, and 32/35 is not unusual. – Criggie May 11 '16 at 9:17
7

We don't do product rec here, but some general advice: You want to find the biggest tires you can fit into the bike, and run them at high pressure. The pressure written on the tire sidewall is useless (the maximum pressure depends on the rim and the tire), but in all likelihood you will be close to or exceeding it on many tires. The particular model of tire won't really make a difference if you're pinch flatting them -- that is a symptom of too low pressure.

Also, riding on a flat tire is bad -- you can damage the rim and wheel that way.

If the biggest tire you can put in at the highest pressure you can run safely doesn't work out for you, consider switching to a rigid mountain bike, where you can easily get 2+ inch tires in, which will easily take 300 lbs.

Note that running at a high pressure leaves you vulnerable to other things like road hazards damaging the wheel. You want the lowest pressure such that the rolling resistance is negligible, you avoid pinch flats, the tire absorbs some of the nature of the surface and keeps you in control of riding (i.e. no bouncing). For a 300+ lb rider, this will be a pretty high pressure on many tires. Also, remember tires are supposed to deflect a bit (visibly when you're on the bike), but not too much. If they don't deflect, they're overinflated.

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    I don't think this advice is actionable - "high pressure" means different thing to different people. – tymtam May 11 '16 at 1:59
  • Its a hard number to quantify. Various people have made charts, but they're all pretty much ad hoc. – Batman May 11 '16 at 9:08
  • Narrower tyres can generally take higher pressures, so he might be better off with a tyre that isn't the largest possible if it can be run at a higher pressure. – armb May 11 '16 at 15:07
  • The pressure ratings on the tires are arbitrary. You can often go quite a bit higher than the top end. The problem with a narrow tire is that you have to run it at a very high pressure which in turn makes any road hazard a potent source of wheel damage.\ – Batman May 11 '16 at 16:05
  • I wouldn't say the pressure ratings are arbitrary. They are what the manufacturer feels safe to guarantee, and what the tire is designed to be used with. As long as you are within that range, there should be no problems with wear on the sides of the tire, or exploding tires. Of course, that means that you won't immediately experience any problems if you slightly exceed the limits. That's the nature of a safety limit. However, you can expect problems when you significantly exceed them. And then the manufacturer will just say: You have been warned. – cmaster - reinstate monica Jul 23 '18 at 21:22
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This is close to my goto answer for tyre issues. Tyres designed for touring use are meant for higher loads and inflation pressures. I run marathon plus on my commuter hybrid. They make a 26x2.0 version which is rated to a load of 260lb per tyre and 70psi inflation (which you could probably exceed a little). It's possble that won't fit your rim (see Sheldon Brown) or your frame/mudguards (flip the bike over and pad the tyre out to test it). But you could go a step thinner.

As you've noted, your weight isn't split equally between the tyres - the back wheel carries more load.

  • Need to also check the rims themselves are rated for the extra pressure. – mattnz May 11 '16 at 9:27
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    @MattNZ fair point, though I haven't seen rims rated to less than that. – Chris H May 11 '16 at 11:56
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You could try converting your tyres to a tubeless system.

I run much lower pressures on my tubeless mountain bike than I used to - they are super resistant to pinch flats. Every now and then I can feel the rear wheel pinching in a way that would previously have caused an instant flat but to date no flats (touch wood!).

I find (anecdotal) that the tubeless tyres seem to lose pressure a little faster than normal inner tubes.

Combine that with regular pressure checks and you should be better off.

  • For a moment I read that as running a solid/foam tire. Which would certainly avoid the flats problem... – Wayne Werner May 11 '16 at 11:56
  • At the cost of a lot of other problems (see various other questions on why solid tires are bad). – Batman May 11 '16 at 12:05
1

Schwalbe Big Ben or Big Apple tires. Maxxis Hookworms.

I'm 450lbs and ride Maxxis Hookworms. Which are 26X2.5 tire. I always ride at maximum PSI. But They might not fit in your forks. I had to buy new forks for the tire to fit.

Another good beefy tire the Schwalbe Big Ben tires. Rated for riders 350lb. Which would most likely fit your bike with no alterations.

-3

just pump it on bigger pressure, then two things can happen; 1) inner tube won't be able to hold pressure -> buy some inner tubes for downhill 2) tyre jumps out of rim -> buy some rims for dirt jumping/downhill, they will hold the tire better

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    Inner tube does not hold the pressure. – ojs May 10 '16 at 17:11
  • The problem is that the most likely time for either of these failures is just when you don't want it. E.g. the tyre jumps off the rim and the tube blows when you hit a pothole at speed. Also, new tyres are cheaper and easier to fit than new rims, and at least as likely to help. – Chris H May 10 '16 at 17:49
  • @ojs bad inner tubes are porous so in that term they do hold the pressure – AshKetchumTheBiker May 10 '16 at 17:52
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    ojs is correct, the tire holds the pressure, the inner-tube holds the air. – Scott Lundberg May 10 '16 at 18:42

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