Kingsong S20/S22 (Confirmed)

[mrelwood]

2 hours ago, enaon said:

My experience with the s18 says that silicone is the way. We no not need grease or anything that dust can stick on, silicone is good way to clean off debris/wash the wheel, and also protects all euc parts and lubricates.

Just to make sure, are you talking about a silicone spray, silicone oil, or some other? Silicone grease and silicone itself do not really seem to lend themselves for “washing”… 

[rolis]

Some Data sheets for Material properties (thermal, mechanical, electrical, physical, ...). Right now I don´t want to filter out the relevant information, but this should be helpful nonetheless.

PTFE: https://laminatedplastics.com/teflon.pdf
POM: https://3faktur.com/wp-content/uploads/2018/07/Materialdatenblatt-Pom.pdf
UHMWPE: https://www.directplastics.co.uk/pdf/datasheets/UHMWPE Data Sheet.pdf
Nylon66: https://www.theplasticshop.co.uk/plastic_technical_data_sheets/nylon_66_technical_data_sheet.pdf

[Paradox]

 

[Eucner]

On 3/11/2022 at 12:35 AM, Freeforester said:

Adam’s observations:

 

This was a major let down. The sliding mechanism is mediocre at the best. The groove should be protected from debris. There should be an internal fender preventing dirt getting into the groove. It is also possible to protected it by curtains, brushes or bands. Unfortunately none of these is very feasible in this application. The sliders needs to be shaped differently. There should be separate wipers at the both ends of the sliders. The edge of slider should prevent dirt getting between rail and slider. Hard sand will wear out soft aluminium and plastic very fast. There should also be a recesses in the sliders to prevent this happening.

The play in the link system wasn't too excessive to my eye. It would be interesting to see it after more usage.

In my opinion the one month recommended maintenance interval is a minimum in clean environment. The wheel should be cleaned after every dirt ride. Also the quality shock manufacturer's recommend full overhaul for their shocks in every 100 - 125 hours. For an active rider this can easily mean less than one months rides. Suspension wheels needs much more maintenance than the non-suspension wheels.

On 3/11/2022 at 5:13 PM, Paul A said:

Perhaps for the sliders, use UHMW/UHMWPE plastics.

UHMW (ultra high molecular weight polyethylene) is an extremely tough, abrasion-resistant, low-cost plastic.

UHMW has an extremely low friction coefficient. It is comparable to PTFE, which also slides well. UHMW has an excellent shock resistance.

Because of its high molecular weight, UHMW is resistant to moisture.

UHMWPE would be a great material for the sliders. Much better than PA, POM or PTFE. Considering the amount of wear shown in Adams video, I'm certain it is something else.  

22 hours ago, fryman said:

At .30 it shows them greasing the channels

 

Nooouuu, there shouldn't be any wet lubricant used in this application. All dirt would get attached into it.

20 hours ago, jrhz06 said:

I’m planning on cleaning the grease off and using TriFlow. Works great on S18.

Tri-Flow is a brand, not a single product. Do you mean their dry lubricant? That could be a good to go.

19 hours ago, Paul A said:

Kevin thinks the slider is plastic.

Kevin puts all materials into 3 categories: alloy, metal and plastic. From this we know the sliders are not metal or alloy .  

9 hours ago, Freeforester said:

It would seem on the face of it that if KS could be persuaded to use the correct type of plastic insert in these friction bearings, they could omit the greasing of the channels, saving them both on manufacturing time and potential for wear related issues in the casings further on down the road, as well as omitting the ‘service each month’ instruction to potential buyers, which is likely to prove to be more of a turn off for more than a turn on?

This is a great suggestion.

4 hours ago, Rollin-on-1 said:

I have white lithium spray...I wonder if that would be a good product to use?  

Wet lubricant is not a good idea here. In any case you should be very careful when choosing a lubricant for plastics. The lubricant can make plastic soft, hard, sticky, brittle or swollen. It should be always tested before use.

Edited March 12, 2022 by Eucner
missing word

[techyiam]

1 hour ago, mrelwood said:

 

 

Many thanks. That's a good shot.

[supercurio]

I read that POM can be 3D printed at 220-230 °C.

Well probably it's gonna be a pain to get it to stick to the print bed but.... challenge accepted!

They'll definitely be ways to make alternative designs for the sliding blocks, or print a bunch of replacement parts in case they're not readily available.

Coming to think of it, the video you linked @mrelwood regarding upgrades of the V11 suspension probably come from the same concept. Will watch it now.

Edited March 12, 2022 by supercurio

[Forwardnbak]

2 hours ago, Paradox said:

 

The S20 seems nicely planted, very stable hitting those roads. The Sherman seems like it is a little more skippy over the pavement, s20 sits into the road nicely. 

[techyiam]

2 hours ago, mrelwood said:

 

 

Many thanks, that's a good shot.

The video was somewhat illuminating on wear, play, and stiction vs length of bearing insert.

[Paul A]

Maybe it could be as simple as this...

 

 

[fryman]

4 hours ago, Freeforester said:

Slick, dry stuff:

 

 

Looks like a lot of companies make this similar product.  Can someone relay this suggestion to KS.

[enaon]

3 hours ago, mrelwood said:

Just to make sure, are you talking about a silicone spray, silicone oil, or some other? Silicone grease and silicone itself do not really seem to lend themselves for “washing”… 

Silicon spray, thinner than water, very nice for cleaning the s18. This was to demonstrate the effect of silicone on a stuck system. 
 

 

[fryman]

Edited March 13, 2022 by fryman
Couple of options based on what the guides are made of.

[enaon]

dry spray holds lubrication effect for more time, but  do not clean the surface. Silicone spray needs frequent applications, but also provides a way to clean the surfaces. I think the dry spray is not a nice match for the s18/s20 "open to debris" system. 

[Forwardnbak]

 

I’m not a tech guy but thought about bike forks this above is from a dirt bike discussion, maybe a similar idea could help keep dust away and things running smooth. 

[Lex Smith]

14 hours ago, mrelwood said:

but the rumored monthly maintenance requirement is just laughable. They know very well that not a single rider can manage such a tight maintenance schedule for more than a few months,

 

I've been maintaining the suspension on my V11 on  a weekly basis since purchasing it many months ago so there is at least a single rider 😅 but I suspect I would be in the minority. 

As an aside I used to maintain my hang glider with the same schedule but there is arguably even more at stake consequence wise for a catastrophic failure. 

[Paul A]

Maybe it wouldn't matter that much if dirt gets into the tubes. 

It might add some resistance/friction, but would it be significant to affect the performance of the suspension?

Thermoplastics are very tough and hard wearing.  The material can be used in ballistics vests.

Abrasion from particles of dirt might not cause damage.

 

 

 

[mrelwood]

8 hours ago, rolis said:

Some Data sheets for Material properties (thermal, mechanical, electrical, physical, ...). Right now I don´t want to filter out the relevant information, but this should be helpful nonetheless.

PTFE: https://laminatedplastics.com/teflon.pdf
POM: https://3faktur.com/wp-content/uploads/2018/07/Materialdatenblatt-Pom.pdf
UHMWPE: https://www.directplastics.co.uk/pdf/datasheets/UHMWPE Data Sheet.pdf
Nylon66: https://www.theplasticshop.co.uk/plastic_technical_data_sheets/nylon_66_technical_data_sheet.pdf

POM was the only one that had a value for friction coefficient. Which is unbelievable to me, as these are all materials touted mainly for their low friction and suitability as bushings and bearings!

6 hours ago, techyiam said:

Many thanks. That's a good shot.

It was a shameless quick copy paste from one of the V11 threads here. I have dozens of photos myself, but this was faster… 

6 hours ago, supercurio said:

I read that POM can be 3D printed at 220-230 °C.

The parts used in the V11 are not regular POM, they are hardened or treated some other way. I have no idea how, or if the S20 ones are also hardened. So 3D printing might not get exactly the same outcome.

 

At least one instance is looking into 3D printing UHMWPE:

https://3dprintscape.com/can-uhmwpe-be-3d-printed/

Once the technique becomes feasible to an end user, I know I’ll finally get my first 3D printer!

 

6 minutes ago, Paul A said:

Maybe it wouldn't matter that much if dirt gets into the tubes. 

It might add some resistance/friction, but would it be significant to affect the performance of the suspension?

Thermoplastics are very tough and hard wearing.  The material can be used in ballistics vests.

Abrasion from particles of dirt might not cause damage.

No, you’re right, the plastic parts would still operate reasonably well. The problem is that they run in tight fitting aluminum channels. Tiny rocks that get squeezed in between will get stuck in the plastic, and will keep scraping the aluminum which then acts like rough grit sand paper to the rest of the plastic, ruining the whole system.

 

[mrelwood]

Just ran into this: For 3D printed parts, HDPE retains many of the properties of UHMWPE:

https://www.tutocad.com/3d-printing/how-3d-printer-hdpe-vs-uhmw/

[Paul A]

A little sceptical of grit managing to penetrate and remain in the tubes.

Gravity is acting to prevent and remove grit.

The very minimal clearance between slider blocks and tubes limits the size of any possible particle ingress

Thermoplastic and aluminium tubes are hard and do not deform to allow grit to be embedded.

Rubber could deform and have grit embedded.

Grease could bind and hold grit.

[mrelwood]

1 hour ago, Paul A said:

A little sceptical of grit managing to penetrate and remain in the tubes.

Gravity is acting to prevent and remove grit.

The very minimal clearance between slider blocks and tubes limits the size of any possible particle ingress

Nothing notable will get in through the top or the bottom, that seems clear. Where the grime/dust/sand/dirt comes in is from the side, between the top and bottom plastic sliders. If I looked at it correctly, dust seemed to have a mm or a few of clearance at all times when entering the non-sealed tube. And this is right next to the tire, where harsh dusty gusts are present even when you ride just calmly to the corner store.

1 hour ago, Paul A said:

Thermoplastic and aluminium tubes are hard and do not deform to allow grit to be embedded.

They can do so, I’ve seen it on the V11. Even reinforced aluminum is still aluminum, and can be carved with a knife. A tiny rock is way harder.

[Eucner]

3 hours ago, Paul A said:

Thermoplastics are very tough and hard wearing.  The material can be used in ballistics vests.

Thermoplastic is not a name for group of super materials. Plastics can be divided into 2 groups: thermoplastics and thermoset plastics. The only difference is how plastic behaves under heat. Thermoplastics will get softer and thermosets will not. Thermoplastics are easily recyclable.

3 hours ago, Paul A said:

Abrasion from particles of dirt might not cause damage.

Aluminium and plastic are soft. They will get damaged. Just look at Adams video.

[Eucner]

9 hours ago, fryman said:

Looks like a lot of companies make this similar product.

Dry lubricants are usually based on graphite, PTFE or MoS₂. Graphite and road salt together can cause corrosion problems with aluminium. PTFE is good at under 230° (446°F). MoS₂ can be really messy. I would pick Teflon or MoS₂ based dry lubricant. A wax lubricant could also work nicely. They are dry to touch.

[Eucner]

4 hours ago, mrelwood said:

POM was the only one that had a value for friction coefficient. Which is unbelievable to me, as these are all materials touted mainly for their low friction and suitability as bushings and bearings!

There are plenty of variables affecting plastics friction coefficient. In many cases it needs be tested in specific application. For marketing and liability reasons manufacturers are reluctant to give exact numbers. UHMWPE alloyed with molybdenum sulfide can have as low as 0,08 CoF. PTFE can even go down to 0,04, but has other restrictions for it use.

[Paul A]

Google searches for:

 

UHMW's coefficient of friction is 0.14 or lower, and it typically does not require lubrication.

http://www.garlandmfg.com/pdf/Extrusions.pdf

 

PTFE's coefficient of friction is 0.05 to 0.10, which is the third-lowest of any known solid material (aluminium magnesium boride (BAM) being the first, with a coefficient of friction of 0.02; diamond-like carbon being second-lowest at 0.05).

https://en.wikipedia.org/wiki/Polytetrafluoroethylene

 

The friction coefficient of POM-C sliding against stainless steel starts at a relatively low friction level of about 0.2 and rises to higher values after 20 h of sliding due to material transfer.

https://www.sciencedirect.com/science/article/abs/pii/S0043164803004101

 

1) The surface of a polymeric material like Nylon 6-6 can be composed by polymer, oligomers, hydrolysis products and water. 2) The value of the friction coefficient of Nylon 6-6 against steel ranges from 0.1 to 1.5 in our experiments.

https://www.sciencedirect.com/science/article/abs/pii/S0167892208710733

 

 

[Planemo]

8 hours ago, Forwardnbak said:

 

I’m not a tech guy but thought about bike forks this above is from a dirt bike discussion, maybe a similar idea could help keep dust away and things running smooth. 

Running oil sponges under the wiper seals has been done for years on MTB forks and I cant think of any that dont these days. Its simple but effective, keeping the stantions lubed with every pass. The sponges, along with low friction SKF wiper seals (as I have fitted to my Rockshox) do work very well together. Pic of sponges for anyone who is wondering where and how they fit:

https://images.app.goo.gl/uRsYR7nCdp6V1bGP7

 

Edited March 13, 2022 by Planemo