S18 Suspension Overhaul

[Feynman]

58 minutes ago, BFE Duke said:

 It's really a job for a lathe...

I agree with that for sure.

[Finn Bjerke]

So just to be clear:

All these overhauls are optional improvements ? Most of the s18 works right out of the box. Batch 2 is prob better with regards to bearings?   Sorry if Im daft Im just not a technical guy and I want to have a functional Wheel for everyday commuting and fun.

[Feynman]

1 hour ago, Finn Bjerke said:

So just to be clear:

All these overhauls are optional improvements ? Most of the s18 works right out of the box. Batch 2 is prob better with regards to bearings?   Sorry if Im daft Im just not a technical guy and I want to have a functional Wheel for everyday commuting and fun.

I would say it's optional.  If you just remove the blocks from the pedal hangers and lube the rails and all suspension joints it will probably be fine.

That said, I wouldn't count on the suspension linkage lasting very long with those lock washers crushing and binding the bearings at points A->D and C.

Edited September 2, 2020 by Feynman

[Finn Bjerke]

Answer much appreciated Sir, I can learn to fix that ... you comments are very helpfull.  Changing those points should be possible even for me.   I have been very close to buy Inmotion v11 instead.  Not so many idiotic mistakes. (I guess)  But I guees ill just buy them washers and stuff. Getting em on a slowboat from China will take a while 

[Finn Bjerke]

Sorry for being daft but the shopping list for fixing suspension linkage is:

??

[Feynman]

28 minutes ago, Finn Bjerke said:

Sorry for being daft but the shopping list for fixing suspension linkage is:

??

Working on it.  I'll post a concise list when I have my suspension back together and happy with how it's working.  One week or less.

[eve]

22 minutes ago, Feynman said:

Working on it.  I'll post a concise list when I have my suspension back together and happy with how it's working.  One week or less.

You mean two lists. One for bushings setup and one for bearings setup. 

[Feynman]

1 minute ago, eve said:

You mean two lists. One for bushings setup and one for bearings setup. 

I'll post my CAD files for bushings if anyone is interested.  I designed them with built in spacers for some of the connections.  

[Feynman]

I've started a 'Final Parts List' with links in the original post at the very beginning of this thread.  I'll update this as I settle on final parts.

[dsd317]

15 hours ago, Feynman said:

I'll post my CAD files

Which CAD program do you use?

[Feynman]

1 minute ago, dsd317 said:

Which CAD program do you use?

Fusion 360

[dsd317]

1 hour ago, Feynman said:

Fusion 360

Nice.  I use Creo for my job, but use a little bit of Fusion 360, Onshape, Shapr, and TinerkCad for my hobbies.

[Feynman]

Update:  the quotes I'm getting for machining custom bushings are ridiculous.  I'm wondering if 3D printing these is an option since I have an F410.  Delrin isn't on the materials list, but I have a query in with their excellent tech support.  If I could 3D print these, that would be so awesome.  The 0.003" resolution of the F410 is better than the 0.1mm tolerances I've been getting from machine shops.  

[BFE Duke]

If you can do it in Nylon, then it miiiight be okay if you achieve good homogeneity. I wouldn't bet my life on it though. Same as before, you will want to overprint the center hole and ream it. Reamers can be bought for like ~$10 a piece. That's for the female part. For the male part, I assume you'll want to make it out of metal. 

By the way, resolution is not the same as tolerance. A print could be set to a 0.003" resolution but the final result could have a 0.050" tolerance. 

[Feynman]

1 minute ago, BFE Duke said:

If you can do it in Nylon, then it miiiight be okay if you achieve good homogeneity. I wouldn't bet my life on it though. Same as before, you will want to overprint the center hole and ream it. Reamers can be bought for like ~$10 a piece. That's for the female part. For the male part, I assume you'll want to make it out of metal. 

By the way, resolution is not the same as tolerance. A print could be set to a 0.003" resolution but the final result could have a 0.050" tolerance. 

It will print Nylon, but I figure I'd try Delrin.  

[BFE Duke]

6 minutes ago, Feynman said:

It will print Nylon, but I figure I'd try Delrin.  

Even better if you can get Delrin to stick. 

Also, if you overprint the outsides and need to sand it down, you can chuck it up on your drill press and use it as a shitty lathe in a pinch for sanding purposes. Careful though cause drill presses spindles cannot handle much side load, so this should be for light sanding only!

[Feynman]

Apparently glass fiber reinforced nylon bushings are standard in mountain bike shock systems.  I ordered a roll of 30% GF nylon filament today.  Expensive, but cheaper than buying a lathe.   

While waiting on that I'll print a set in ABS to test fit

Edited September 3, 2020 by Feynman

[slaweks82]

Hi everyone,

I did full tear-down my S18 to fix suspension. I bought some 10x16 washers (DIN988), but quickly run-out of them, as these bearings needs >3mm spacers to start working, and I ended up making 10.2x15.9mm aluminium spacers, used them where "B" and "C" touches frame, also replaced spring washer, and 0.5mm between "A"-"D" (all these A,B,C,D I'm referring to Feynman picture from one page before), and removed big washer, and add 3x0.5mm instead, to redirect force on inner bearing race.

Tighted bolts, and bearings starts to work - inner fixed and arms rotating freely!  Staring assembly and, and on each step I did suspension test without shock. It was floating, I was very happy, until I tided up an engine. This is wired, but it creates the most friction on the tubes. I tried both scenario from two assembly video, tried also many other variations with tighting bolts in may orders and every time I tideup 2nd side (not important if I started engine wire side 1st or as 2nd) its starts to generate friction. Tried with pedals and block ON and OFF, same result. It's still way better, then before, but I"m worried. Any one had similar issue?

This is my tubes after 400km, and spacers I made: https://photos.app.goo.gl/N9CUSWs79NgrDfrd6

Regards

Slawek

 

 

[yon]

hello 

I just found this forum and now a little horrified to find out the issues you have been having with the suspension.  Mine is still not with me and here is the reason why.

I thought I would post the c&p text I had in a recent email from kingsong ireland with whom I purchased mine, letter dated 24/08/20

 

 

Dear Customer,

As of Thursday 20th August your S18 shipment was due to leave China. 

Due to some minor quality problems found on the suspension of the S18, the departure of same has been postponed. These problems aren't mayor however, an improvement on the suspension bushings of the S18 is currently taking place. At the moment we are in close communication with factory and awaiting confirmation of the new departure date. 

We would like to apologise for this delay. We are aware factory is already rectifying these problem and will soon have our shipment ready for shipping.

You will get notified about the new departure date by email as soon this late improvement is completed.

Dear Customer,

As of Thursday 20th August your S18 shipment was due to leave China. 
Due to some minor quality problems found on the suspension of the S18, the departure of same has been postponed. These problems aren't mayor however, an improvement on the suspension bushings of the S18 is currently taking place. At the moment we are in close communication with factory and awaiting confirmation of the new departure date. 
We would like to apologise for this delay. We are aware factory is already rectifying these problem and will soon have our shipment ready for shipping.
You will get notified about the new departure date by email as soon this late improvement is completed.
 

Dear Customer,

As of Thursday 20th August your S18 shipment was due to leave China. 
Due to some minor quality problems found on the suspension of the S18, the departure of same has been postponed. These problems aren't mayor however, an improvement on the suspension bushings of the S18 is currently taking place. At the moment we are in close communication with factory and awaiting confirmation of the new departure date. 
We would like to apologise for this delay. We are aware factory is already rectifying these problem and will soon have our shipment ready for shipping.
You will get notified about the new departure date by email as soon this late improvement is completed.
 

-- 

 

Best regards,

IRELAND

 

Dear Customer,

As of Thursday 20th August your S18 shipment was due to leave China. 
Due to some minor quality problems found on the suspension of the S18, the departure of same has been postponed. These problems aren't mayor however, an improvement on the suspension bushings of the S18 is currently taking place. At the moment we are in close communication with factory and awaiting confirmation of the new departure date. 
We would like to apologise for this delay. We are aware factory is already rectifying these problem and will soon have our shipment ready for shipping.
You will get notified about the new departure date by email as soon this late improvement is completed.

 

Dear Customer,

As of Thursday 20th August your S18 shipment was due to leave China. 
Due to some minor quality problems found on the suspension of the S18, the departure of same has been postponed. These problems aren't mayor however, an improvement on the suspension bushings of the S18 is currently taking place. At the moment we are in close communication with factory and awaiting confirmation of the new departure date. 
We would like to apologise for this delay. We are aware factory is already rectifying these problem and will soon have our shipment ready for shipping.
You will get notified about the new departure date by email as soon this late improvement is completed.
 

[Feynman]

I should have just done this from the start... 

[Finn Bjerke]

would it be possible to make a video showing the most neccessary upgrades. Is it possible to make the most important things without dismantling the whole wheel? 

6 hours ago, Feynman said:

I should have just done this from the start... 

What is this ?

[Rehab1]

13 hours ago, yon said:

Dear Customer,

As of Thursday 20th August your S18 shipment was due to leave China. 

Due to some minor quality problems found on the suspension of the S18, the departure of same has been postponed. These problems aren't mayor however, an improvement on the suspension bushings of the S18 is currently taking place.

 

6 hours ago, Finn Bjerke said:

would it be possible to make a video showing the most neccessary upgrades. Is it possible to make the most important things without dismantling the whole wheel? 

I’ve communicated with Ewheels about providing their customers with a complete OEM S18 suspension upgrade kit once KS finalizes the new design. Their response:

Hello Dan,

It's a good point, the introduction of suspension has added another dimension of complexity to post-sales support. Rest assured, we will most certainly stock these for warranty replacement, repairs and sales. 

 

@Feynmanand others have dedicated so much time and effort refining the S18 suspension over the past month and should be commended! 
 

I hope KS respects their R&D and implements the comprehensive upgrades and then provides dealers/ customers with a free suspension modification upgrade kit containing all of the necessary components along with an installation video. 

Edited September 4, 2020 by Rehab1

[eve]

I sent the ecodrift suspension comparison to my seller. He asked Kingsong directly. Kingsong said there is no problem with the suspension. @Rehab1

 

Edited September 4, 2020 by eve

[Feynman]

8 hours ago, Finn Bjerke said:

would it be possible to make a video showing the most neccessary upgrades. Is it possible to make the most important things without dismantling the whole wheel? 

What is this ?

Magic.  Set of bespoke bushing for the S18.  These are in ABS, so I'll just use them for a test fit.  The real ones will be printed in glass fiber reinforced nylon.

Sure.  When I do put all of this back together for good (hopefully) I'll at least take step-by-step pics.  Unfortunately, the only connections you can get into without disassembling the wheel are the A-D connection between arms and the shock connections (see pic below for lettering reference).

 

Edited September 4, 2020 by Feynman
better pic of arms

[Feynman]

Here's my design for the A->D connection.  There is a 2.5mm bushing inserted into D, then an 18mm thrust bearing, the bushing in A extends into D and rests against this thrust bearing.  The bearing is enclosed by the D pocket and protected from dirt, etc.  

The rough fit is good, but there's still friction from the screws on the bushings.  I'm thinking I'll create a pocket in the back of the D bushing for a smaller thrust bearing.  This will make the post/screws bound to the outside arm, but let the inside arm rotate freely.  If I ditch the metal washer on the outside of pocket A, I could do the same for this bushing, but then the only thing holding the arms together at this joint is the press-fit of the bushings.  Maybe this is ok?

Edited September 4, 2020 by Feynman
spelling