Sherman tire pressure equivalent to other wheels?

[roghaj]

I must have some Jesus walking on EUC powers because its working just fine. 

[MrRobot]

35 minutes ago, roghaj said:

I must have some Jesus walking on EUC powers because its working just fine. 

Well whatever you're comfortable with I suppose. I just don't know how that'd be enjoyable personally. I'm 200 pounds and run a little under 30 psi. Once I go much past that potholes and large cracks in the road become very rough on the knees and it feels twitchy. But I guess if you were used to an mcm that makes sense. But if I hit a pothole without really having time to prepare for it it could easily send me on my ass at higher psi. Having a little give in the tire for shock absorption is safer imo especially when riding at 30+ mph. If you don't push higher speeds I guess it might be OK. 

Edited October 6, 2020 by MrRobot

[Bridgeboy]

On 10/5/2020 at 6:54 PM, MrRobot said:

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

It depends upon how much everyone weighs, guys. I ride my KS18XL at around 50 PSI but I typically weighed 260-LBS+ when I started riding. I've actually lost a bunch of weight recently so I might want to rethink this, I'm just under 240-LBS now naked (Keto meal plan; eating proteins and fat, no carbs).

Hearing that @ShanesPlanet is 130-LBS...holy cow, he is literally 1/2 of me. And he rides at literally less than 1/2 the PSI I ride at (on KS18XL).

My Sherman is supposed to deliver tomorrow. But I asked for a street wheel to be installed. So that is another factor to consider in this discussion. It won't behave the same as the typical standard knobby tire.

[brockj]

On 10/8/2020 at 9:13 PM, Bridgeboy said:

It depends upon how much everyone weighs, guys. I ride my KS18XL at around 50 PSI but I typically weighed 260-LBS+ when I started riding. I've actually lost a bunch of weight recently so I might want to rethink this, I'm just under 240-LBS now naked (Keto meal plan; eating proteins and fat, no carbs).

Hearing that @ShanesPlanet is 130-LBS...holy cow, he is literally 1/2 of me. And he rides at literally less than 1/2 the PSI I ride at (on KS18XL).

18XL is my current wheel and my current (naked) weight is about the same as yours. I used the ride about 42 PSI but now 38 feels perfect. 

I have a Sherman on the way (well... in December) so I'm curious what pressure your running on yours if you got it.

[.....]

1 hour ago, brockj said:

18XL is my current wheel and my current (naked) weight is about the same as yours. I used the ride about 42 PSI but now 38 feels perfect. 

I have a Sherman on the way (well... in December) so I'm curious what pressure your running on yours if you got it.

i ride my 18L at 22-25psi and I ride the sherman at 20-22psi. Im 130lbs. I'm betting youll ride it just a little lower than your 18XL, as it has a MUCH sturdier sidewall on the Vet.   the ks18 series and sherman make a great set. Add an mten and you're good to go! Fwiw, I envision that you will still ride the shit out of your 18, for those times when comfort and ease are the agenda. Speed and distance is the sherman's wheelhouse. COngrats!

Edited October 31, 2020 by ShanesPlanet

[Bridgeboy]

17 hours ago, brockj said:

18XL is my current wheel and my current (naked) weight is about the same as yours. I used the ride about 42 PSI but now 38 feels perfect. 

I have a Sherman on the way (well... in December) so I'm curious what pressure your running on yours if you got it.

I'm riding at about 33-psi which the Kenda street tire says its rated for, for our weight. I rode the 18XL closer to 50 PSI. The scooter tire of the Sherman is much more robust; the 18XL is like a toy in comparison.

I might add that my feet never get fatigued/numb on the Sherman riding on soft mode and a 2° forward pedal tilt. Even after a long 60-mile ride.

My feet get numb on the 18XL fairly quickly. So for me it's the opposite of what @ShanesPlanet predicts in the above post. The Sherman is way, way more comfortable than the 18XL. But Shane is tiny compared to us so the ergonomics of how the wheel behaves is going to be different for him. The heavy 77-lbs wheel really helps lower our combined center of gravity and it makes a huge difference.

Edited October 31, 2020 by Bridgeboy

[.....]

2 hours ago, Bridgeboy said:

I'm riding at about 33-psi which the Kenda street tire says its rated for, for our weight. I rode the 18XL closer to 50 PSI. The scooter tire of the Sherman is much more robust; the 18XL is like a toy in comparison.

I might add that my feet never get fatigued/numb on the Sherman riding on soft mode and a 2° forward pedal tilt. Even after a long 60-mile ride.

My feet get numb on the 18XL fairly quickly. So for me it's the opposite of what @ShanesPlanet predicts in the above post. The Sherman is way, way more comfortable than the 18XL. But Shane is tiny compared to us so the ergonomics of how the wheel behaves is going to be different for him. The heavy 77-lbs wheel really helps lower our combined center of gravity and it makes a huge difference.

We definitelty have different wheels. I can attest that the sherman IS very comfortable while going fairly straight. Its the weight on the leg with no RollNZ cover during start/stop that isnt so friendly. That, and having to hang so far off the side in high speed turns takes a LOT more effort. Perhpas we also have a slightly different riding style? Good to hear you are enjoying yours so much.

[Bridgeboy]

30 minutes ago, ShanesPlanet said:

We definitelty have different wheels. I can attest that the sherman IS very comfortable while going fairly straight. Its the weight on the leg with no RollNZ cover during start/stop that isnt so friendly. That, and having to hang so far off the side in high speed turns takes a LOT more effort. Perhpas we also have a slightly different riding style? Good to hear you are enjoying yours so much.

I just responded to another post of yours, and my response is just as relevant here so I'll copy and paste: It has to be the differences in our firmware:

When you are about to choose your wheel in DarknessBot to connect to it, what does it list your wheel as being? Mine is LK1158. I'm told that means it's the 1,158th Sherman made.

Yours is probably a very low number and the original F/W that has pedal dip.

Once you get the firmware update module you'll probably be good to go.

Also, I do use the stock power pads that came with it and they help I'm sure.

 

 

[.....]

mine showing lk779. Still don't know what firmware that would be. Im assumign the first one. I tried the stock pads for my obligatory gas station video run, they did help.I also set tilt to +1 back, per @Mike Sacristan suggest, among others. I found them to be a little too narrow and my leg angle isnt the same front and back. I've since been trying to get my own made. I may have a winner, but havent had a chance to ride last few days. Good foam aint cheap, but I've enough to make 3 more sets, in case it takes that many more tries.

Maybe I need to update darknessbot? It sees the wheel, but when I select it, it says 'hardware not supported". I dont care that much, I only use DB in the studio when I dont want to open my tiny lemfo. Hell, probably need to update that damn thing to the newest eucw, once seba lets me know its out.

Its good to hear that you don't have pedal dip. Hell, you can even set a forward tilt and not scrape? HOLY  SHIT! Surely you arent considering upgrading your firmware? One thing is for certain, firmware update is a risky gamble. Its not uncommon it fixes one thing and breaks 3 others. If yours works good, leave it and consider yourself blessed. Makes me happy, at least i know its possible to have a wheel without dip.

Edited October 31, 2020 by ShanesPlanet

[Bridgeboy]

I always keep Darknessbot updated to latest version. So that might be it. You have the 779th Sherman off the assembly line and mine is 1,158th.

I don't know if I'll update the firmware or not, but Jason said he's sending me a module. I'll wait until I hear whether it's good or bad before just doing it.

I posted the thread along with video about the pedal tilt. Here:

It's incredible hard to get the Sherman past 40-mph unless I tilt the pedals forward. Tilting them backwards makes it almost unrideable. Probably couldn't get it to go over 30-mph with any backward tilt at all. I haven't seen anyone recommend backward tilt; I guess I just missed those threads. It's night and day difference on how much better I can control the wheel just by adjusting pedal tilt forward. Backward = bad and forward = good.

At least that's the way it works for me on my Sherman with firmware 1053.0.

However, with more expereince on the wheel I'm sure controlling the wheel at any pedal tilt, or level, will become easier over time.

[brockj]

Do either of you tilt your pedals on the 18XL? (Since you both have them.) Tilting back 1 or 2 degrees feels great on it. I like it for the same reason that I believe you said you like tilting forward: it gives me easier access to acceleration and just feels easier on the feet.

The idea of tilting forward gives me the willies for some reason. I wonder if that's a matter of stance.. or wheel. 

[.....]

35 minutes ago, brockj said:

Do either of you tilt your pedals on the 18XL? (Since you both have them.) Tilting back 1 or 2 degrees feels great on it. I like it for the same reason that I believe you said you like tilting forward: it gives me easier access to acceleration and just feels easier on the feet.

The idea of tilting forward gives me the willies for some reason. I wonder if that's a matter of stance.. or wheel. 

I ride my 18L at 0% tilt(mten also obviously). I mucked with it when I first got it, but decided to just leave it. I tend to stand right leg very dominant, as I have a bad hip and knee on the left side.  . Its quite troubling when I evaluate my high speed turns and the geometry isnt mirrored for left and right .Oddly, i ride scooter and skateboard with left foot forward. Im a lefty, so its the norm for us

Edited November 1, 2020 by ShanesPlanet

[Bridgeboy]

On 10/31/2020 at 11:29 PM, brockj said:

Do either of you tilt your pedals on the 18XL? (Since you both have them.) Tilting back 1 or 2 degrees feels great on it. I like it for the same reason that I believe you said you like tilting forward: it gives me easier access to acceleration and just feels easier on the feet.

The idea of tilting forward gives me the willies for some reason. I wonder if that's a matter of stance.. or wheel. 

I never attempted to change my 18XL pedals to anything other than level. It never occurred to me to do so.

The only reason I thought to experiment with pedal tilt on the Sherman is because it's a feature, you just press a button to go in 1° increments forward or backward up to 5° maximum either way. And, while riding level I was having extreme trouble getting the Sherman to go fast. No matter how hard I leaned forward it just would not go. So, I started experimenting with tilt and voilà, I was able to accelerate fast and reach top-end speeds with forward pedal tilt. Backward tilt makes it much worse to make the wheel move.

But since my feet do get numb on the 18XL and they don't on the Sherman I probably will try forward tilt on the 18XL at some point in the future. Right now it's hard to even think about the 18XL because if I have time to ride, I'd much rather be riding the Sherman.

 

Edited November 14, 2020 by Bridgeboy

[Dominic Winsor]

I’ve just reset mine to 30psi. It feels pretty good for me as a 104kg rider. Certainly smooth on road and capable off road. 

My tyre was not properly centred on the wheel and I only just go around to fixing this. It was causing a vertical oscillation above about 26 mph. I completely deflated the tyre and manhandled it around the rim until it looked better placed. Then I added a little air and checked again. Once I was happy I put it back up to 30. It is really nice to ride now. Cured the wobble. 

Edited November 14, 2020 by Dominic Winsor
Typo. Cantered —> centred

[Bridgeboy]

5 hours ago, Dominic Winsor said:

I’ve just reset mine to 30psi. It feels pretty good for me as a 104kg rider. Certainly smooth on road and capable off road. 

My tyre was not properly cantered on the wheel and I only just go around to fixing this. It was causing a vertical oscillation above about 26 mph. I completely deflated the tyre and manhandled it around the rim until it looked better placed. Then I added a little air and checked again. Once I was happy I put it back up to 30. It is really nice to ride now. Cured the wobble. 

It took me about 7 or 8 tries until I finally got the tire seated properly.

[brockj]

Now that I have the Sherman, for my 106kg (235 lbs) weight, I found 30 psi on the knobby to feel about as hard as the 18xl at 40 psi. I'm finding 24-26 psi to be a sweet spot, as this still feels responsive but has a suspension-like quality that inspires more confidence cruising over the usual potholes and gravel on my route.  Hopping off curbs are non events, just a soft bounce. This tire is amazing.

[Dominic Winsor]

10 hours ago, brockj said:

…has a suspension-like quality that inspires more confidence cruising over the usual potholes and gravel on my route.  Hopping off curbs are non events, just a soft bounce. This tire is amazing.

Isn't it just? It's so smooth, yet so capable. Love it. It works really nicely on the trails too. I found out at the weekend that it doesn't work so well on really wet mud… it was like clay.

[Daley1]

Spent the day riding Sherman at 32psi.Way to hard and uncomfortable on this knobby tyre. Going over tree roots on an asphalt path gets u just about airborne.(105kgs)On the Ks 16s i ride at about 40psi .I think i,m going down to about 25 psi ,to play next time.No-one under 200lbs should b riding this tyre higher than 30psi and possibly a lot less. Raced a couple of guys around the velodrome on their bikes and nearly came undone with high speed cornering pedal dip.Funny as Fxxk! Still blew them away but nearly died in the process!

[Whitebeard]

Does anyone have any update to the wider 6mm rim, what the riding psi should be for a 200 lb rider? 

I personally have my Sherman pumped to 33 psi, but finding it very bouncy in uneven roads. I haven't tried lowering the psi because I worry I'd crack the rim more easily. 

[.....]

I'm not as heavy at 130lbs, but I run 20psi on mine. Same as the stock v1 rim with offroad tire and the new v2 rim with pirelli. I'd say you're near the ballpark. Best you can do is lower it just a tiny bit and keep testing. I think the rim issue is a QC material issue. Its such a crapshoot that either you have a decent rim or don't. Im not sure tire pressure is as big a factor as manufacture, excluding too low of course. As long as you arent bottoming out the tire into the rim, I can't see how a few pounds either way, are going to cause a problem. Either the rim is sh*t or it aint, is my uninformed opinion. Fwiw, my tire upgrade lessened some of the rebound of the offroad tire, at same pressures. FOr those worried, I'd definitely upgrade to a tire that isnt junk. Something with a little more sidewall and meat along the casing.

@brockj I now ride my 18XL with a negative 2degree tilt. Compromise in braking but much easier for me to just glide at speed. I run same tilt on the sherm unless heading down a steep mountain.

Edited July 7, 2021 by ShanesPlanet

[Rawnei]

Depends on the tire more than the wheel, the Kenda 262 that comes with the Sherman is rated for max 33, in my experience up to 30 it feels fine but above it feels wobbly and bouncy, I can't even imagine riding it at 35 or even yet 40.

I have the same tire on my MSP HT and I rode it a lot on 25-26 before bumping it up to 28, so 25-30 feels like the best place to find your sweetspot on that tire.

[Planemo]

11 hours ago, ShanesPlanet said:

 I think the rim issue is a QC material issue. Its such a crapshoot that either you have a decent rim or don't. Im not sure tire pressure is as big a factor as manufacture, excluding too low of course. As long as you arent bottoming out the tire into the rim, I can't see how a few pounds either way

This.

I also believe that everyone saying you have to run high pressures on the sherman is missing the point. If you're not bottoming the rim but are still cracking them then you dont dont need more pressure, you simply have a shit rim. In fact, I would argue more pressure (if you're not bottoming the rim) will actually lead to more chance of a rim failure as all that road force has got to go somewhere if the tyre isnt yielding.

I run 23 on my sherman, and I ran 25 on my msx. I am about 95kg geared up. Neither have shown any issues, but then I do take caution with kerbs etc. I wouldnt want to run more on the sherman as to me it feels a little less compliant than the msx as it is. Prob due to the sherman tyre being less compliant than the 5102 to start with.

[DjPanJan]

Last +-300km done on +-26 Psi sherman knoby stock tire. I pump it to 28Psi month ago or more and self deflate to actual 26psi confortable range fine ,tire heat up after some km/miles to "hot" state. My plan is next ride pump it to 30 and try if some diference hapend.

Im using shaomi air pump for measure/change pressure.

 

Update on sherman stock KENDA knoby(offroad) tire i try 30PSI after 200km im back to 28 PSI.

Edited July 20, 2021 by DjPanJan

[EUC AZ]

40 psi.  Nice and responsive

[Rich Sam]

39.5 PSI, installed TPMS system and note that after 5 minutes of riding pressure jumps to 42PSI.  I weight 235 lbs.

guys in our riding group have taken 120fps vids of what 40 psi looks like and bouncing up and down.  Rider weighed around 200 lbs.  To simulate what it looks like when you hit a pothole, hook up high speed camera and film your self rolling stiff legged over a 2x4.  Look how much that 2x4 eats into the tire. These tests will tell you where your pressure should be.  All it takes is a gentle kiss on those aluminum walls and your rim is toast.

I hit a hidden pothole last night going around 30 mph that thing jarred me so hard I think I lost a tooth filling LoL.  Rim held though at > 40 psi.

ewheels has told me they recommend at least 40 psi, any lower, and you risk rim damage.