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Sherman tire pressure equivalent to other wheels?


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I usually ride at 37psi on an msx 84v 1600wh wheel. I weigh 190lbs

Am I going to want to use roughly the same to get the equivalent feel for the Sherman? Maybe a little higher since it's a heavier wheel? 

Knobby tire if that makes a difference. 

What have been your experiences with tire pressure on this wheel? 

Edited by MrRobot
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12 hours ago, Andy Huang said:

Sherman tire specifications indicate that the maximum tire pressure is 33psi.

Wow that is low. Wonder why. Is that an actual maximum or just like the maximum it would be if it was on a motorcycle? Not sure what the maximum is for an msx to compare it to... 

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26 minutes ago, Andy Huang said:

The maximum value marked on the side of the tire is 33psi. This tire is 2.75-14, which is the marking method for motorcycle tires.

Ah so it can go considerably higher without it being a real problem then. Jason's tire pressure guide says:

According to industry sources, they say that tire manufacturers have a tendency to use overly conservative ratings in order to minimize their warranty obligations, but in the internal testing departments, the actual loads that the tires are subjected to, before failure, can be upwards of 5-10x greater than the marked specification.

https://www.ewheels.com/guide-tires-appropriate-pressures-electric-unicycle/

Edited by MrRobot
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  • 2 weeks later...

Wow, you guys run it high. I just came back from my first ride and my tire was nice and soft at 15psi. I couldnt imagine how much bouce it would be if it were at 35psi. Hard to compare with other tires, as sidewalls and tread tend to change casing characteristics by a LOT. As far as max pressure, I'd say stop when it turn into a rock, nevermind what the damn sidewall says.

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Do you guys find a significant drop in high speed wheel agility when running higher pressure? When you go from 20psi to 35psi, it becomes very difficult to make quick turns at speed (going around a corner) and the wheel seems much more determined to go straight! I have been completely blown away but how much psi affects driving profile. I`m sure there is some interesting physics at play as spinning discs possess strange and counter-intuitive properties.

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  • 2 weeks later...

@ShanesPlanet @MrRobot

Wrongway! chanel  make range test at 33PSI Adam(wrongway!) need some minutes use  Sherman on 33PSI he was shocked how diferent and "hard" is Sherman on 33PSI.

Wrongway later in video speak how 33Psi is too mutch unconfrtable when he ride ??interlocking paving?? 8:32 (i dont know what this terain name is in english)

I hope this video help somebody gain more info about Strman and PSI.

/little Offtopic/ I use on 16X 38 PSI same on my MSP 2500W( lower psi is great i know but i am just too heavy to (rim safely) enjoy lower PSI on any EUC)

   

 

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Im riding the Sherman at 32psi, I weigh 165 lbs.  Ive tried lower pressures however the wheel just feels sluggish. I'm still amazed at some of these lower pressures Im reading about. I guess it's what you are used to. Ill experiment some more..

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I run my sherman at 20psi and its dandy. I began at 15psi. I like sidewall deflection, a smooth ride and would rather rely on my knees for big bumps while not worrying about tire bounce at speed on small shit. My 30-40mph 30mile ride to my local gas station was at 20psi(offroad tire), i enjoyed it immensely. I ride at 25psi on my 18L, 20psi on my mten. Im 130lbs.

10 hours ago, zege said:

I wonder how low you can go before you get flats?

On a tube'd tire, you can go extemely low. I would suspect that if you go too low, eventually the tire casing will eat the tube. Or, youll suffer a tube pinch if rim bites it when bottoming the tire out.

Edited by ShanesPlanet
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I also had 20psi on the MSP with the CST-C186 and that was the best ride. But since I had enough dents on my 16X rim to repair and the speed through the woods increased a lot, I increased to 22psi. :efee612b4b:

Weight 172lb.

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Heh, I had 30-35 psi on thé cross tyre and found it disturbingly soft (though comfy) went up to 40, feels more normal to me (used to 50psi on 18x2.5inch 18XL) I weight 70Kg.

Edited by null
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3 hours ago, ShanesPlanet said:

I run my sherman at 20psi and its dandy. I began at 15psi. I like sidewall deflection, a smooth ride and would rather rely on my knees for big bumps while not worrying about tire bounce at speed on small shit. My 30-40mph 30mile ride to my local gas station was at 20psi(offroad tire), i enjoyed it immensely. I ride at 25psi on my 18L, 20psi on my mten. Im 130lbs.

On a tube'd tire, you can go extemely low. I would suspect that if you go too low, eventually the tire casing will eat the tube. Or, youll suffer a tube pinch if rim bites it when bottoming the tire out.

Or worse as i found out the rim will buckle and maybe split ,with the weight of the Sherman + body weight  

off road Ride is great at low PSI on non suspension wheel but not at the expense of a new motor  

 

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46 minutes ago, Gaz Bon said:

Or worse as i found out the rim will buckle and maybe split ,with the weight of the Sherman + body weight  

off road Ride is great at low PSI on non suspension wheel but not at the expense of a new motor  

 

Wow, you've buckled a sherman wheel already? I tend to keep soft knees to prevent bottoming out. Old habit from the bicycle days I guess. Still is a valid concern tho, as sometimes you get caught off guard and a low pressure does bite ya. I havent split any rims yet, I'm more concerned of bending them. SOrry to hear about the rim, what it cost you to fix?

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On 9/19/2020 at 12:03 PM, ShanesPlanet said:

Wow, you guys run it high. I just came back from my first ride and my tire was nice and soft at 15psi. I couldnt imagine how much bouce it would be if it were at 35psi. Hard to compare with other tires, as sidewalls and tread tend to change casing characteristics by a LOT. As far as max pressure, I'd say stop when it turn into a rock, nevermind what the damn sidewall says.

As a reference, what pressure do you have on the 18Ls? 

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Just now, ShanesPlanet said:

25psi on the 18L at 130lbs, street.

Wow I ride it at 35. I used to ride it at 40 but got a bit of brown-pants moment at speed going over a crack and decided to lower it. I used to really like how twitchy it was at high pressure, so that I'm used to a cushier tire I don't know how the hell I could ride in such squirrelly conditions 😂

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28 minutes ago, travsformation said:

Wow I ride it at 35. I used to ride it at 40 but got a bit of brown-pants moment at speed going over a crack and decided to lower it. I used to really like how twitchy it was at high pressure, so that I'm used to a cushier tire I don't know how the hell I could ride in such squirrelly conditions 😂

its all just compromises for me. 25psi on the 18 and 20psi on the sherman, is a little on the softer side. I usually ride the same road, so there's not much for potholes and cracks that I'm not already aware of. I have been taken by surprise once or twice, and thos pressures got me close to a rim check. But I was also close to eating shit, so I call it a wash. If I'm wanting to ride faster with less effort and am willing to compromise a little comfort, I up the pressure by 5psi = 30psi on 18 and 25psi on the sherman. This is still a pretty soft ride, but its a lot more nimble and requires less user input. Any higher than 30psi, it gets too easiy to begin a rebound/bounce that I dont really like. At 25-40mph, a harsh (yet tiny) road imperfection that isnt abosrbed by a softer pressure, becomes a hop and my feet get too light or off the pedals. I'd imagine if i was wanting to go further and didnt assume I'd be hitting much speeds, I would inflate quite a bit more. In the end, its personal preferance and by tire/wheel. It is fun to see how we all vary.

Edited by ShanesPlanet
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4 hours ago, Melody Ko said:

I'm currently liking 28 psi. 

Yes that's about what I settled on too but I haven't played with it too much out of fear of putting too much wear and tear on the valve on this shitty tube. Going to attempt to swap it out today and then I'll mess with different pressures more. 

Edited by MrRobot
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Just got mine today and put it at 30 and it felt soft.  Bumped it up to 40.  Still feels really weird to me.  I miss my ACM2 1600wh.  I sold it for the sherm.  I hope I warm up to this wheel.

-Roger

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7 hours ago, roghaj said:

Just got mine today and put it at 30 and it felt soft.  Bumped it up to 40.  Still feels really weird to me.  I miss my ACM2 1600wh.  I sold it for the sherm.  I hope I warm up to this wheel.

-Roger

40?!? Jesus! You're going to bounce off every little bump like a trampoline. Be careful! 😬

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