Sticky Sherman S suspension

[wstuart]

On 2/1/2023 at 2:58 PM, supercurio said:

@Planemo I was thinking about how to measure the load necessary to break stiction in that case, since I can't remove the spring.

I'll give it a shot tomorrow, taking an average to break from stiction at the (inaccurate as a result) sag point of the suspension under the wheel's weight.

Regarding temperatures since it was a common question, the result appears identical at room temps 6h later as it was at approximately freezing temp earlier.

 

23 hours ago, MrMonoWheel said:

I have noticed my batch  1 SS has some stiction but its not noticable when riding. 

My Sherman S has 320 miles and my suspension has the same amount of stiction as both of yours.  It has not gotten any better or worse since I first got it.

I have batch 1 bearings that are still good, but I've only ridden on a wet road once - for a mile.

Also my wheel is misaligned like yours.  The gap is bigger on the right on the front, and bigger on the left on the back. This can't be good.  I wonder if this is why the wheel feels unstable above 30mph.  Also when I do a freespin test the wheel shakes a little like something is unbalanced

I absolutely love the performance of this suspension.  I highly recommend playing with your settings.  I had several s22 riders try my wheel at a group ride and they said they liked my suspension better - which actually surprised me.

@MrMonoWheel would you be willing to help me out when it comes time to replace my bearings?  I'm in San Diego too.

Edited February 2, 2023 by wstuart

[supercurio]

Thanks for the input @wstuart
The motor on my unit is reasonably well aligned with the battery boxes. Oddly the mudguard, well aligned in the front is shifting completely to the side on the rear. Something to investigate.

A rider with stock S22 original sliders as baseline will find any Sherman S better 100% of the time, no doubt. Even perfectly clean and the best grease.
A rider with S22 on CNC POM rollers with the correct spring for its weight: that one's stiction is essentially undetectable and the ride incredible.

Edited February 2, 2023 by supercurio

[wstuart]

11 minutes ago, supercurio said:

Thanks for the input @wstuart
The motor on my unit is reasonably well aligned with the battery boxes. Oddly the mudguard, well aligned in the front is shifting completely to the side on the rear. Something to investigate.

A rider with stock S22 original sliders as baseline will find any Sherman S better 100% of the time, no doubt. Even perfectly clean and the best grease.
A rider with S22 on CNC POM rollers with the correct spring for its weight: that one's stiction is essentially undetectable and the ride incredible.

They had the pro rollers on theirs.  I thought their suspension was better than mine.  I still plan to get an s22 when they finally get their board and motor sorted out..... I'm 6'8" 220 so I need reliable torque. 

[supercurio]

1 hour ago, wstuart said:

They had the pro rollers on theirs.  I thought their suspension was better than mine.  I still plan to get an s22 when they finally get their board and motor sorted out..... I'm 6'8" 220 so I need reliable torque. 

It's an interesting case, KS messed up their rollers implementation before shipping them to the extent that eWheels is switching to a 3rd party one (by ningning)

KS increased stiction by adding far too many POM wheels, swapping to the wrong type then failing with tolerances. How bad is the results showed in KS sliders "upgrade" installation video.

The reference is the fine tuned Russian original 4x rollers design. I have a set from Alexander Vodnev, the original inventor.

Good point tho, for the next comparison I'll be more specific on which CNC rollers model 👍

 

Edited February 3, 2023 by supercurio

[supercurio]

On 2/2/2023 at 3:44 AM, Planemo said:

It is quite surprising how much force is required when you actually put a number to it. Using hands I didn't think the totally stock forks were too bad but they measured a lot more than it felt!

I'm discovering at the moment how much you are right.
While preparing a video to demonstrate how much stiction is present, I'm trying to find household items heavy enough to break the stiction.

Last one I tried: an Inmotion V10F.
Yep! A whole other wheel on top of the Sherman S and still no suspension movement apparently. I'll need to confirm that but this is getting ridiculous.

Edited February 3, 2023 by supercurio

[Paul D]

On 2/1/2023 at 6:36 PM, Planemo said:

 

This is exactly what we have with EUC's unfortunately. Very few riders have experience with MTB suspension and even fewer have the knowledge to say 'hmm this isn't right, I'll strip this bugger right down' and instead simply ride on blissfully unaware. Unless it's shockingly bad of course. But on the flip side I guess many folk would consider even poor suspension better than no suspension so there is that.

I have a lot of experience with some pretty nice mtb suspension. I can’t get mine to stick at all with 250 ish on the odometer

[MrMonoWheel]

On 2/2/2023 at 2:58 PM, wstuart said:

 

My Sherman S has 320 miles and my suspension has the same amount of stiction as both of yours.  It has not gotten any better or worse since I first got it.

I have batch 1 bearings that are still good, but I've only ridden on a wet road once - for a mile.

Also my wheel is misaligned like yours.  The gap is bigger on the right on the front, and bigger on the left on the back. This can't be good.  I wonder if this is why the wheel feels unstable above 30mph.  Also when I do a freespin test the wheel shakes a little like something is unbalanced

I absolutely love the performance of this suspension.  I highly recommend playing with your settings.  I had several s22 riders try my wheel at a group ride and they said they liked my suspension better - which actually surprised me.

@MrMonoWheel would you be willing to help me out when it comes time to replace my bearings?  I'm in San Diego too.

First off, I would be happy to help you out when its bearing swap time 

Secondly, I wonder how much the crooked wheel could be affecting the suspension. If the wheel is crooked and there is uneven lateral pressure on the forks I could only assume it is causing extra friction leading to some of this stiction. When I freespin my wheel it also shakes like something is out of balance. I haven't thought anything of it but maybe all of this is why I keep getting weird behavior at higher speeds.

[Paradox]

7 hours ago, MrMonoWheel said:

Secondly, I wonder how much the crooked wheel could be affecting the suspension. If the wheel is crooked and there is uneven lateral pressure on the forks I could only assume it is causing extra friction leading to some of this stiction.

It will be interesting to see if the crooked wheel can be mounted correctly and if this will reduce stiction.  We all await your next maintenance post.

[mrelwood]

8 hours ago, MrMonoWheel said:

When I freespin my wheel it also shakes like something is out of balance. I haven't thought anything of it but maybe all of this is why I keep getting weird behavior at higher speeds.

It’s definitely worth checking out. Does the tire run straight when you do the free spin? If not:

 

[wstuart]

12 hours ago, MrMonoWheel said:

First off, I would be happy to help you out when its bearing swap time 

Secondly, I wonder how much the crooked wheel could be affecting the suspension. If the wheel is crooked and there is uneven lateral pressure on the forks I could only assume it is causing extra friction leading to some of this stiction. When I freespin my wheel it also shakes like something is out of balance. I haven't thought anything of it but maybe all of this is why I keep getting weird behavior at higher speeds.

Sweet man.  I'll totally take you up on that.  I have an ewheels wheel so I'm sure Jason will help me out when bearing swap time comes, but TBH I would rather have someone who knows the wheel helping me work on it.

INTERESTING!  so yours behaves weird at high-speed too??  Mine gets pushed around by the wind.  Taking off the Suron seat has help with this, but the wheel still feels sketchy above 30mph.  I cant put my finger on what it is, I'm just not confident at that speed the way I am on my EX or my Sherman Max. It might be the wheel, it might be that I suck at riding, it might be my 6'8"frame getting pushed by the wind on these high pedals.....or any combination of these. If it's the wheel, I was thinking the vibration might have something to do with it...... vibration probably isn't helping the bearings either.

I wonder if the vibration is coming from the tire being slightly misaligned on the rim (I'm gonna try to straighten mine) or the wheel being misaligned in the shell..... or both

I really think the way the wheel is constructed might contribute to the wheel misalignment...... 

I have an idea.  Before you take your wheel apart, can you measure the gaps between the battery and tire case on front and back?  Then measure after you reassemble and see if they change.  If they do, then I think we could point to the wheels peacemeal construction as a source of wheel misalignment.

 

Edited February 4, 2023 by wstuart

[wstuart]

4 hours ago, mrelwood said:

It’s definitely worth checking out. Does the tire run straight when you do the free spin? If not:

 

Yup I need to do that.  My tire is not running straight on the rim.  I'll try that and report back on the vibration. 

[wstuart]

5 hours ago, Paradox said:

It will be interesting to see if the crooked wheel can be mounted correctly and if this will reduce stiction.  We all await your next maintenance post.

I wonder that too, but I also wonder what "mounting correctly" would require.  Because of the way the batteries, suspension and plastic top part peice together, I wonder it have some kind of an assembly jig with help with proper alignment of these parts as the wheel is assembled.  

IMHO, the construction of the wheel seems prone to "tweak", where slight variations in the alignment of the wheels pieces would produce varying degrees of sticky suspensions and wheel misalignment.  I think the fact that some wheels are less sticky than others supports this idea

[Paradox]

Just now, wstuart said:

I wonder it have some kind of an assembly jig

A workmate work bench could work.  It looks like the workbench Eevee's used.

[supercurio]

@wstuart agree and since the Sherman S has rebound dampening on one side, compression dampening on the other, forces trying to get the system misaligned are introduced each time the suspension travels with battery boxes connected to each other by the controller box serving as bridge.

What I'm reporting here is on an out of the box wheel but I wonder how things are gonna evolve over the next few years for most of the the Sherman S suspensions.
Although for now I have no clue if the problem comes form one/both of the shocks, machining of the motor shaft or parts attached to it, the battery boxes, the controller box, the interface between them or a problematic assembly. It's gonna be a long troubleshooting.

Edited February 4, 2023 by supercurio

[wstuart]

2 hours ago, Paradox said:

A workmate work bench could work.  It looks like the workbench Eevee's used.

Yeah I saw a video of a guy in Boston using one of those while tearing down a Sherman S.   If I had room I'd get one. 

[wstuart]

2 hours ago, supercurio said:

@wstuart agree and since the Sherman S has rebound dampening on one side, compression dampening on the other, forces trying to get the system misaligned are introduced each time the suspension travels with battery boxes connected to each other by the controller box serving as bridge.

What I'm reporting here is on an out of the box wheel but I wonder how things are gonna evolve over the next few years for most of the the Sherman S suspensions.
Although for now I have no clue if the problem comes form one/both of the shocks, machining of the motor shaft or parts attached to it, the battery boxes, the controller box, the interface between them or a problematic assembly. It's gonna be a long troubleshooting.

I agree.  This could take a while.  I think in 2 years when they release the "Sherman S Max V3", most of this will be ironed out and we will have the perfect wheel (maybe with a smart BMS and hall sensor redundancy!)

I do want to add though that despite all of these bearing/wobbly shortcomings, I am still blown away by the performance of this wheel and I am extremely pleased with it.  The fact that I get to ride this amazing wheel for the first 6 months/year of its release to me outweighs these issues and design flaws I'll have to put up with.  I'm riding more than ever now because I LOVE riding this wheel.  In a year or 2 I'll sell this wheel for like 2 grand and buy whatever new Sherman S comes out.  

However, I do still find the rare electronic issues in this first batch to be a little troubling, and I would have expected more.  Hopefully @MrMonoWheel electronic glitch is a rarity.  

[supercurio]

I put the Sherman S upside-down to check the stiction and couldn't resit to take a peek behind the kickstand frame.

Like a friend was suggesting, there might already be metal to metal friction, and that could cause the loads of stiction here. Speculating.

Edited February 5, 2023 by supercurio

[MrMonoWheel]

On 2/4/2023 at 6:24 AM, mrelwood said:

It’s definitely worth checking out. Does the tire run straight when you do the free spin? If not:

 

During my initial inspection when I first got the wheel this is one thing I checked, and it seems to be acceptably straight on the rim. Its just the entire motor/wheel combo is crooked in the chassis. 

 

On 2/4/2023 at 10:25 AM, wstuart said:

Sweet man.  I'll totally take you up on that.  I have an ewheels wheel so I'm sure Jason will help me out when bearing swap time comes, but TBH I would rather have someone who knows the wheel helping me work on it.

INTERESTING!  so yours behaves weird at high-speed too??  Mine gets pushed around by the wind.  Taking off the Suron seat has help with this, but the wheel still feels sketchy above 30mph.  I cant put my finger on what it is, I'm just not confident at that speed the way I am on my EX or my Sherman Max. It might be the wheel, it might be that I suck at riding, it might be my 6'8"frame getting pushed by the wind on these high pedals.....or any combination of these. If it's the wheel, I was thinking the vibration might have something to do with it...... vibration probably isn't helping the bearings either.

I wonder if the vibration is coming from the tire being slightly misaligned on the rim (I'm gonna try to straighten mine) or the wheel being misaligned in the shell..... or both

I really think the way the wheel is constructed might contribute to the wheel misalignment...... 

I have an idea.  Before you take your wheel apart, can you measure the gaps between the battery and tire case on front and back?  Then measure after you reassemble and see if they change.  If they do, then I think we could point to the wheels peacemeal construction as a source of wheel misalignment.

 

I rode my light little V11 for over a year maxing it out at 35-37 daily and it always felt extremely planted and like it was on rails, going wherever I pointed it. I rode it in storms that had wind gusts knocking fences over but the wheel just felt like an extension of my legs and I never thought about it. On the sherman S, there has been a handful of times where I will just be riding straight and all of a sudden it feels like a magnet is pulling my wheel off to one side, and no matter how hard I fight it the wheel just keeps wanting to go to the left or right. I have to slow down significantly, wait for the adrenaline rush to wear off, and then continue on my way. Honestly its stopped me from riding at higher speeds because there were a few times where if I hadn't gotten it under control in time I would have crashed hard. When I asked around people said its wind, but I have never experienced anything like that before, its absolutely terrifying.

 

On 2/4/2023 at 10:36 AM, wstuart said:

I wonder that too, but I also wonder what "mounting correctly" would require.  Because of the way the batteries, suspension and plastic top part peice together, I wonder it have some kind of an assembly jig with help with proper alignment of these parts as the wheel is assembled.  

IMHO, the construction of the wheel seems prone to "tweak", where slight variations in the alignment of the wheels pieces would produce varying degrees of sticky suspensions and wheel misalignment.  I think the fact that some wheels are less sticky than others supports this idea

If you look back in this thread towards when the wheel was first announced, my biggest complaint was the lack of a solid U-structure formed by the suspension and motherboard housing. Instead the wheel relies on the joined batterybox-motherboard connection to get that structure. As you said, any misalignment will cause the suspension to not function as it should. There's a reason motorcycles/bicycles have the suspension forks connected together by at least one single member, if not two or three. 

I don't really know what my plan is to get things reliable and straight, but I am certain I will figure something out.

 

On 2/4/2023 at 10:38 AM, Paradox said:

A workmate work bench could work.  It looks like the workbench Eevee's used.

Harbor freight sells one too!

https://www.harborfreight.com/tool-storage-organization/workbenches/folding-clamping-workbench-with-movable-pegs-47844.html

[wstuart]

37 minutes ago, MrMonoWheel said:

 

I rode my light little V11 for over a year maxing it out at 35-37 daily and it always felt extremely planted and like it was on rails, going wherever I pointed it. I rode it in storms that had wind gusts knocking fences over but the wheel just felt like an extension of my legs and I never thought about it. On the sherman S, there has been a handful of times where I will just be riding straight and all of a sudden it feels like a magnet is pulling my wheel off to one side, and no matter how hard I fight it the wheel just keeps wanting to go to the left or right. I have to slow down significantly, wait for the adrenaline rush to wear off, and then continue on my way. Honestly its stopped me from riding at higher speeds because there were a few times where if I hadn't gotten it under control in time I would have crashed hard. When I asked around people said its wind, but I have never experienced anything like that before, its absolutely terrifying.

Yes!!!! I know exactly what you are talking about.   I can think of 3 instances where the wheel was going hard to the right and I had to do a full lean left turn to keep it going straight.  I've never had a wheel do this before on the wind.  

Things to note - this always occurred in strong gusty wind situations.  - it always resulted in my wheel going to the right.

I would like to say it was just the wind causing it but the problem is that it's inconsistent.  There are times when I get hit by strong winds and the wheel doesn't get "blown off the road".  I wondered if maybe it was a combination of wind and train-tracking from the tire.

Here are 2 things I've done that have seemed to help.

1. I removed the Suron seat from the wheel.  I think this was acting as a sail and catching wind that would tip the wheel over.  After removing it I experienced less movement of the wheel in wind and more stability overall.

2.  I switched from hard mode to medium mode today.  This COMPLETELY TRANSFORMED THE WHEEL!  In hard mode I was having to full press against my pads to maintain high speeds.  I think this extreme front lean/pressure in combination with wind gusts was generating the high-speed instability.  In medium mode I don't need to even have my shin touching the pad to cruise at high-speed.  I've only done 10 miles testing with this, but it seemed like wind gusts had MUCH less effect on the wheel in medium mode.  If you are in hard mode, try medium.  

Edited February 6, 2023 by wstuart

[Paul D]

[Paul D]

Road around the soft desert dirt of south Utah. Had a blast. Wheel performed great. Beyond what I can push it so far. It got pretty dirty. It’s easy to hop over rocks and get a little air. 
 

I also blasted up a paved road just west of Zion NP that was really steep. No problems at all. 

I tested for sticky suspension today. Still really smooth. I also checked all the bolts while cleaning it. Some tightened a very small amount. 

[Paul D]

[Paul D]

I’m still figuring out if I like medium or hard mode better. 
 

I think medium for paved and hard for dirt?  

[Paul D]

Virgin river. 
 

once off the paved or hard packed roads, the dirt was pretty soft, but still rideable. 

[Paul D]

Lol, just realized where I’m posting. 
 

I meant to post in main SS thread.