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Tire question

Old 10-23-20, 06:35 PM
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Irishred
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Tire question

For a 26 X 1.95 knobby rated at 40-65 psi,,,I am 160 lbs body weight. I ride lots of roots and rocks with no suspension. Any idea as to how low a psi I can take this tire safely?
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Old 10-23-20, 08:02 PM
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The primary determinant of how low you can go is when you start pinch flatting.

For a ballpark starting point, I’d say you are most likely Ok going down to something like 33/38 front/rear. However, you may end up being able to go a lot lower than that.

The only way to know is to keep dropping each tire by a psi or two and riding it. Keep doing that until you have an issue with pinch flats, and then go back up a couple PSI.
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Old 10-24-20, 12:34 AM
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Originally Posted by Kapusta View Post
Keep doing that until you have an issue with pinch flats, and then go back up a couple PSI.
Or if you don’t want to fix a lot of flats, do forty
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Old 10-24-20, 09:14 AM
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Originally Posted by Darth Lefty View Post
Or if you don’t want to fix a lot of flats, do forty
Sure, but he will be likely missing out on a lot of comfort, control, and performance.

At the very least run the front lower than the rear.
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Old 10-24-20, 10:14 AM
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I guess your asking how low because you’re getting beat up and losing grip at the pressure you are currently ridding at. I think part of your pressure question has to do with how well you are able to pick lines, avoid impacts, and get over things. Roots, rocks, and 26x1.95 rigid is not a good recipe.

While I hate the lower till you flat, I don’t have much of a better suggestion. I’ve run 40 through rocks with front suspension at a little more weight and 26x2.1.

Maybe 38 front/40 rear and see how it goes. If it is still too much pressure, take it down by a psi. I’m purely “guessing” that maybe you’ll end up at 35/38.

John
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Old 10-24-20, 10:42 AM
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I realize some people do not deal with getting a pinch flat, but “lower until you flat” is - in the end - the least painful way to find out what gives best results. Fixing 1 or 2 flats to find the best comfort, traction, and performance, seems a whole lot better than riding around indefinitely with a harsher ride, and poorer traction.

But that’s just me.

Fwiw, back in the late 90s when I was running 2.0 tires with tubes, I ran 30/35 f/r with no issues. i was around 175 at the time.

Last edited by Kapusta; 10-24-20 at 12:38 PM.
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Old 10-24-20, 03:00 PM
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Thanks for wisdom

Thanks to all for your wisdom...I'll try the 30/35 (front/back and see how that goes.
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