Tire Pressure
02-23-14, 11:02 AM
#26
Should Be More Popular
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BTW is that your pic next to the chart?
02-23-14, 11:09 AM
#27
Should Be More Popular
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I had to look up the meaning. Was surprised it's named after a county in North Carolina:
[After Buncombe, a county of western North Carolina, from a remark made around 1820 by its congressman, who felt obligated to give a dull speech "for Buncombe".]
[After Buncombe, a county of western North Carolina, from a remark made around 1820 by its congressman, who felt obligated to give a dull speech "for Buncombe".]
02-23-14, 11:10 AM
#28
Glad to see someone else is riding in the 75 - 90 psi range. Makes me cringe when I read about folks putting 140 psi in their tires. I compromise between rolling resistance and comfort, with a tilt towards comfort. Riding tubulars I can get away with slightly lower pressure.
02-23-14, 11:21 AM
#30
Fixie Infamous
I ride 80/85, at +200#.
But I can't pinch flat.
But I can't pinch flat.
02-23-14, 11:54 AM
#31
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https://www.bikeforums.net/showthread...tip-of-the-Day
Tire Width=20: Pressure(psi) = (0.33 * Rider Weight in lbs) + 63.33
Tire Width=23: Pressure(psi) = (0.33 * Rider Weight in lbs) + 53.33
Tire Width=25: Pressure(psi) = (0.33 * Rider Weight in lbs) + 43.33
Tire Width=28: Pressure(psi) = (0.33 * Rider Weight in lbs) + 33.33
Tire Width=32: Pressure(psi) = (0.17 * Rider Weight in lbs) + 41.67
Tire Width=37: Pressure(psi) = (0.17 * Rider Weight in lbs) + 26.67
Example: You are 150lbs running 28's
Pressure (psi) = (0.33*150) +33.33 = 82.83psi (rear)
Front Pressure = .9*Rear Pressure = .9*82.83psi = 74.55psi front
Tire Width=20: Pressure(psi) = (0.33 * Rider Weight in lbs) + 63.33
Tire Width=23: Pressure(psi) = (0.33 * Rider Weight in lbs) + 53.33
Tire Width=25: Pressure(psi) = (0.33 * Rider Weight in lbs) + 43.33
Tire Width=28: Pressure(psi) = (0.33 * Rider Weight in lbs) + 33.33
Tire Width=32: Pressure(psi) = (0.17 * Rider Weight in lbs) + 41.67
Tire Width=37: Pressure(psi) = (0.17 * Rider Weight in lbs) + 26.67
Example: You are 150lbs running 28's
Pressure (psi) = (0.33*150) +33.33 = 82.83psi (rear)
Front Pressure = .9*Rear Pressure = .9*82.83psi = 74.55psi front
02-23-14, 10:53 PM
#32
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Thanks for all the replies guys. I tried 105/110 PSI F/R today, off from my usual 120/120. N. Jersey roads were poop to begin with but 4 snow storms (or 5? I stopped counting...) and all the plowing, they turned into a veritable poop show with pot holes several feet across. I mean these roads would do the cobbles of the Koppenberg justice... Anyways, I really enjoyed the ride quality of the reduced pressure and I'll probably play around some more, maybe drop both tires by another 5 PSI. As always, you guys have been a great help. Thanks!
02-24-14, 08:51 AM
#33
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What's the easiest way to determine the delta in efficiency as it relates to tire pressure? Buy a power meter? What if I'm running 23s on a wide wheel (23mm wheel on Flo 30s)?
02-24-14, 09:36 AM
#34
After reading this thread I tried lowering my tire pressure to 100psi from the usual 110 that I'd been running for years. Running ROL Race SLs(23mm wide) with Vittoria Zaffiro Pro 700x23s.
I like it - smoothes out the road a bit and doesn't seem to slow me down any.
I like it - smoothes out the road a bit and doesn't seem to slow me down any.
02-24-14, 09:53 AM
#35
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Those Michelin and PSImet pressure are still way too high for me. Both recommend 110-120 PSI given my weight, with no account for different weight on the front and rear tires.
I used the Tire Drop article, and my bathroom scale to determine the actual weight on both the front and rear tires. I came out in the 85-90 range for the front, and 95-100 for the rear. So I've been running 90/100 for some time on 25c tires.
I used the Tire Drop article, and my bathroom scale to determine the actual weight on both the front and rear tires. I came out in the 85-90 range for the front, and 95-100 for the rear. So I've been running 90/100 for some time on 25c tires.
02-24-14, 10:36 AM
#36
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I bought a thin michelin tire and it's harder to pump up. I hope I put it in the rim correctly without any pinches but I got up to 90psi and then it got tough. The cheaper "normal" tires will pump to 120psi no problem.
02-24-14, 10:39 AM
#37
Still can't climb
lower tire pressure. you won't regret it.
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coasting, few quotes are worthy of him, and of those, even fewer printable in a family forum......quote 3alarmer
No @coasting, you should stay 100% as you are right now, don't change a thing....quote Heathpack
coasting, few quotes are worthy of him, and of those, even fewer printable in a family forum......quote 3alarmer
No @coasting, you should stay 100% as you are right now, don't change a thing....quote Heathpack
02-25-14, 12:49 PM
#38
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So....let's try this out from the start and make sure you got the formula correct to begin with. What size tires are you running and what is your weight?
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02-25-14, 01:28 PM
#39
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