Rubbing/grinding sound from KS18XL while weight is on one side

[Marty Backe]

19 minutes ago, svenomous said:

Thanks @Marty Backe. I’m hoping not to have to drill out the screws, but will if I must. Maybe I can find hex bolts of the same size to replace them? Anything I should watch out for, to ensure safety, like material (steel, nickel, ...?). Any other tips from those with experienced at dealing with KS hardware?

The machine screws that they use are nothing special. I would just use a generic matching screw. The load is distributed across 6-screws, so there's no need to find high-strength screws, IMO.

Hope you can get them out without drilling.

[Seba]

1 hour ago, svenomous said:

Thanks @Seba. The side covers each use 17 screws, of which 15 are very short and 2 are longer, if I remember correctly. Are the side cover hex screws you mentioned the short ones, and you just keep using the 2 longer Phillips screws?  What about Torx instead of Hex, since for hex you usually end up using a T or L key, while for Torx you generally use a more “normal” straight diver? Wondering which would be more convenient. I agree that Phillips is a bad idea for screws like these, especially the bigger higher-torque ones used for the pedal hangers. Stripped Phillips is something I see (and cause!) often.

Originally M3x10 screws were used in KS-18L and first batches of KS-18XL, but later KS got several reports of breaking posts, causing side covers to be loose. So they reinforced screw posts by screwing the posts from the wheel chamber side also, effectively reducing remaining post thread height. But this only aplies to the posts used to screw side covers and this is why there are two screw lenghts used. However you can use M3x6 screws everywhere, as there is enough length of thread. Torx screws will be good as well - just use whatever is available to your or what tools do you have. Instead of inix, you can also use black steel screws, they are also very sturdy.

PS. I also suggest you to reinforce posts with hot glue. This is easy and will provide much better protection in case of impact, because even with factory reinforcement there is still too small area over which impact forces are distributed.

 

[travsformation]

4 hours ago, svenomous said:

So that's where I stand.  If anyone has a suggestion for how to get these screws off successfully, I will try again.

Maybe, before you drill them out, you can try one of these (I wouldn't recommend using impact drive, chisel or grinder though)

And I totally agree with Seba on replacing them with allen key heads

 

[travsformation]

20 hours ago, NylahTay said:

I'm just under 200lbs/90kgs. For me it feels like the top of the wheel is rubbing the edge of the casing, but I don't know what the inside looks like. I've learned to simply not ride with one foot. I use mine as my main mode of transportation and have already put over 500kms on it.

It's worth pointing out, that still might be worth getting that sorted out. Putting a lot of kms on the wheel with a misaligned tire (if that's your case) could cause issues further down the road (as well as considerably shorten your tire's lifespan)

20 hours ago, NylahTay said:

Since I average 40-50kmh, I don't ride with one foot off very much  

Now that's what I call a badass!

(Please tell me you fully gear up to ride at those speeds)

[erk1024]

6 hours ago, svenomous said:

If anyone has a suggestion for how to get these screws off successfully, I will try again.

Here is a link on amazon for the GrabIt tool: https://smile.amazon.com/gp/product/B000H6PM32/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

Is this something that could be fixed by changing the position of where pedals attach to the axis of the wheel? 

@NylahTay  BTW, the alignment of my wheel seems to be OK.

Edited May 11, 2019 by erk1024
clarification

[Marty Backe]

7 hours ago, Seba said:

Originally M3x10 screws were used in KS-18L and first batches of KS-18XL, but later KS got several reports of breaking posts, causing side covers to be loose. So they reinforced screw posts by screwing the posts from the wheel chamber side also, effectively reducing remaining post thread height. But this only aplies to the posts used to screw side covers and this is why there are two screw lenghts used. However you can use M3x6 screws everywhere, as there is enough length of thread. Torx screws will be good as well - just use whatever is available to your or what tools do you have. Instead of inix, you can also use black steel screws, they are also very sturdy.

PS. I also suggest you to reinforce posts with hot glue. This is easy and will provide much better protection in case of impact, because even with factory reinforcement there is still too small area over which impact forces are distributed.

 

Over two thirds of the posts on my KS18XL broke. I removed the broken bits and attached wood to the inner shell and then used wood screws in place of the machine screws to reattach the side panels.

KingSong used to make really strong shells. Their quality has really dropped. Maybe they hired some ex-Gotway employees 

[null]

Just as side note on screws, if you change you might as well go for Torx rather than Allen/hex as is takes more torque before stripping.

extra side note about screws: if you have a mini grinder you can cut the head so it works with a flat head screw driver.

[svenomous]

Today I had a chance to go to the hardware store.  Boy are they understocked on metric screws.  For most types they have 1-2 baggies, with 1-3 screws in each one.

Anyway, I managed to get 10 of the right size M6-1.0x16mm Allen drive bolts, but had to make up the deficit with 2 hex socket bolts.  So the first type is driven by 5mm hex key (Allen key), and the other type by a 10mm hex socket.  Actually, maybe the hex socket is the best way to go, although 5mm Allen allows for quite a bit of torque before there's a stripping problem.

For the M3-0.5x6mm screws I found some Allen-driven ones, but not enough for the whole case, and they were socket heads (instead of pan/button heads).  I don't like that these use 2.5mm hex keys.  I've seen a lot of 2mm and 2.5mm hex key screws get stripped in the bicycling world.  4mm is the smallest I find reliable for any amount of torquing.  So, I will want to replace these later with something like Torx.

Brought it all home and decided to use what I had managed to get, and to attempt that re-alignment.  So, having read up on "how to extract a stripped Phillips screw," I first removed all the screws I could get with the P2 screwdriver, and it turns out only one of the 12 screws was too badly damaged to turn.  On that last screw I then tried the "rubber band" method, where you place a rubber band over the screw head to help the screwdriver head grab on, but that didn't work.  Next (before resorting to actually drilling out the head) I tried to use a Dremel with a cutting disk to cut a slot, and then to use a large flat-head screwdriver...and it worked!  Got the screw out.

Inserted the new bolts, with the lock washers and blue thread locker in place (just like the old screws), left them all loose, and played with the shell, tightening the bolts a little bit at a time.  Each time I got the shell centered and started tightening on either side, the right side of the shell started moving in toward the tire again.  In the end I held the shell in an exaggerated position with as much gap on the right as I could make, and started tightening the new bolts (10 Allen hex and 2 socket hex).  When I was done, the shell still looked closer to the tire on the right side.  Very disappointing..but:

After putting the outer shell back on, and while I was already messing with the wheel, I decided to Slime the tire, too, which I hadn't gotten around to yet.  Let the air out, got the valve out, squeezed in 6fl.oz. of the stuff, screwed the valve back in, and before airing up I gave the tire a good squeeze all along the rim on the right side, to see if I could get it to realign a bit away from the right side.  Pumped up to 45psi and checked alignment.  It looks centered now!  I don't know if this is due to playing with the tire, or if it happened while putting on the outer shell, or if maybe I got it better aligned while putting on the hanger bolts (and didn't notice the improvement).  In tomorrow's ride I'll see if it's stopped rubbing.  Hopeful!  Will report back!

Oh, and as for screws/bolts, I've placed some orders on Amazon for Torx-drive M6's and M3's. I also ordered some more hex socket M6's, as I'm thinking maybe hex socket is the best way to drive those bigger bolts.  Once I have everything and have decided between Torx and hex socket for the bolts, I'll open everything up and replace all the bolts/screws one more time to make everything consistent.  Right now I have a mixture of 5mm Allen, 10mm hex socket, 2.5mm Allen, and Phillips, which makes me cringe to think about.

[erk1024]

4 hours ago, svenomous said:

I've placed some orders on Amazon for Torx-drive M6's and M3's

Could you share the links? I'm sure I'll have to replace mine at some point...

 

[svenomous]

9 hours ago, erk1024 said:

Could you share the links?

Sure, although keep in mind there are quite a lot of options to choose from, so these are based on some sorting and filtering (as many listings are in quantities of 100 or 1000 or even more), and in some cases just choosing almost randomly.  Not all are Prime btw.  All that said, here's what I ordered last night.

Qty 1
M6-1.0 x 16mm Flanged Hex Head Bolts Flange Hexagon Screws, Stainless Steel A2-70, DIN 6921, 25 PCS
https://www.amazon.com/gp/product/B07Q4LN4RP

Qty 1
uxcell M6 x 16mm Fully Threaded Stainless Steel Hex Head Screw Bolt 30 Pcs
https://www.amazon.com/gp/product/B019ETHMKS

Qty 2
M6 Button Head Torx Socket Cap Machine Screw,304 Stainless Steel,Pack of 10-piece (M6 x 16mm)
https://www.amazon.com/gp/product/B07CTL27FK

Qty 4
(10) M3 x 6mm Stainless Steel Button Head Torx Socket Cap Screws, ISO 7380 / DIN 9427, A2 Metric Coarse Thread, 6Lobe / Star Drive - MonsterBolts (10, M3-0.50 x 6mm)
https://www.amazon.com/gp/product/B07NWQH16J

Qty 2
(10) M3 x 8mm Stainless Steel Button Head Torx Socket Cap Screws, ISO 7380 / DIN 9427, A2 Metric Coarse Thread, 6Lobe / Star Drive - MonsterBolts (10, M3-0.50 x 8mm)
https://www.amazon.com/gp/product/B07NWZ46YH

Quantities are enough to provide all needed screws, plus extras.  This does not include any screws that might be needed once I eventually get deeper into the case to access the mainboard, etc.  No idea what's being used there. 

The first 3 are different versions of M6-1.0 x 16mm bolts for the pedal hangers.  I couldn't decide between hex heads, flanged hex heads, or Torx cap heads, so I ordered all 3, and I'll decide after they arrive.  The 4th one is the M3-0.5 x 6mm screw that makes up the majority of the outer case screws (the ones under the LED strips, 10 on each side).  T10 Torx cap heads.  The last one is the same product as the 4th one, but slightly longer (8mm) to be used for the remaining 5 outer case screws on each side, the ones under the pads.  I know Seba said that the 6mm screws will work all around, but decided to get slightly longer screws for the positions under the pads, to more closely match the lengths used there by KingSong.  All of these are A2 stainless steel, unlike many of the ones I was able to get at the hardware store last night, which had zinc plating or were black oxide.

Thanks again to @Seba for providing the sizing info and A2 stainless steel recommendation, which helped me zero in on what I needed while standing in the "fasteners" aisle of the hardware store, with about 20 billion little packets of screws, bolts, washers, nuts along 100ft of aisle space.  Bewildering.  Too bad the metric selection is so limited at Home Depot, so that I had to resort to online ordering.

[svenomous]

Did a ride today (and another coming...see my post about these in my separate "learner" thread), and the situation is much improved.  In fact despite being a little OCD about this type of thing, I consider the issue resolved and won't try to make further adjustments.  Visually the wheel is now centered in the case, both fore and aft.  While riding, there's no rubbing noise anymore during normal straight and turning travel.  The only time I'm able to get some rubbing going is if I put significant weight on the right foot, thereby flexing the right side of the case against the wheel.  If I put all my weight on the right foot, the rubbing is quite loud, but not quite as bad as before.  As I said, though, in normal riding the wheel is now as silent as a KS wheel gets, not counting the motor whine.  Problem fixed, and I learned a bunch of new stuff about the wheel, and the community came through for me in diagnosing and fixing!  Next time I open the case I will probably even follow the advice to hot-glue around all the screw posts to reinforce them, so I won't get any broken posts later.  Thanks again to all who commented and gave info/advice.

[erk1024]

4 hours ago, svenomous said:

All that said, here's what I ordered last night.

Thanks for the links!  

[travsformation]

@svenomous glad you were able to sort this out, and thanks for the links!!!

I must say, seeing this issue you've had, and the fact it's not an isolated case, is not great news in terms of KS quality control. There should be no issues of this sort with brand new, $2K+ wheels...

[meepmeepmayer]

I'm mostly surprised you were able to alleviate/fix this issue in the first place lol.

And we can add "Why are wheel well clearances so damn small?" to the list of flabbergastingly unnecessary questions we have for the manufacturers and their inexplicable decisions and oversights of utterly predictable issues.

@Jason McNeil Could you advocate for bigger wheel well/tire clearances next, if you get the chance? Thanks

Edited May 13, 2019 by meepmeepmayer

[NylahTay]

 

 

 

On 5/11/2019 at 5:29 AM, travsformation said:

Now that's what I call a badass!

(Please tell me you fully gear up to ride at those speeds)

Motorcycle helmet and jacket.  I'm starting wish I got the Moster as going 35mph/60kmh would be handy. I tend to travel the side rodes in my hometown where the speed limit is about 30mph/50kmh, and use the bike lane whenever possible, but I still find myself needing to go a tad bit faster to keep with the flow of traffic whenever there is no bike lane. I'm constantly getting the "Please decelerate" or whatever it says when I've hit the max speed. lol

Just caught up to this thread, wow! Thank you everyone for posting. 

[svenomous]

An update: all the screws/bolts I ordered arrived, so today after a short ride I decided to open the wheel again and replace the hardware, while also attempting another realignment to further fix the slight lopsidedness that still existed.

During disassembly I discovered some damage to the inner shell at the bolts that attach to the pedal hangers, due to over-torquing last time I did this.  Cracks, gouged plastic (by the metal-toothed lock washers on the bolts, and even some missing plastic where a whole corner just cracked right off.  A disaster that had me cursing myself for minutes.  I applied hot glue to fill in cracks, rebuild the damaged corner,  and reinforce the holes.  Looks OK but hope it works and lasts.

The flanged hex-driven bolts were a no-go, because their heads are too high and the outer case no longer fits.  I've settled on the 10mm hex-driven bolts (the non-flanged ones), with wide plastic washers to distribute the load (and reduce the chance of further damage).  I've discarded the metal lock washers and will rely solely on Loctite (thread locker, removabe blue type) to prevent the bolts backing out.  I will also of course try to be more careful with torque.

Realigned the case again, and visually it looks even better centered now.  In fact it looks perfectly centered, although I haven't had a chance to ride yet.  I should probably re-run calibration as well, since the case must have shifted a tiny bit in the realignment, and the accelerometers are on the mainboard at the top of the case.  The difference is probably too small to make a difference, but why not, for peace of mind.  Will do it before the next ride.

Some of the inner case screws and all the outer case screws are replaced with T10-Torx-driven screws.  Had to use wrong-size (too large) washers for most of them, because I only had a few M3 washers.  The screw button heads are a bit too small to be used on their own without washers.  Ordering some M3 washers right after I post this.

In doing all this I went as far as unplugging all the cables and pulling the case off the wheel, just to see what it looks like under there for future reference (such as if I have to change a tube or tire.  While I was there I also checked the pedal hanger bolts and the screws holding the covers on the motor.  Wasn't adventurous enough to further disassemble to get at the mainboard, although some day I want to do that to see if I can rig up a battery tap.  No hurry.

[Slartibartfast]

On 5/11/2019 at 3:49 PM, svenomous said:

 

It's a bit hard to see but they actually look more like Posidriv rather than Philips bolts to me:

That may explain some of your trouble: ¯\_(ツ)_/¯

[mrelwood]

7 hours ago, Slartibartfast said:

It's a bit hard to see but they actually look more like Posidriv rather than Philips bolts to me:

That may explain some of your trouble: ¯\_(ツ)_/¯

That is a great point, and many do not indeed know the difference.

But so far all those pedal bracket screws I’ve seen have been regular phillips heads. I think the ones in the picture are just stripped a bit.

I have also seen screws in Chinese gadgets that look like regular phillips heads, but grab clearly better with a suitable PZ bit. Although, that may well be just a lucky accident taken the known Chinese tolerances and lack of actual design...

Edited May 26, 2019 by mrelwood

[svenomous]

@Slartibartfast, I agree with @mrelwood that these were Phillips screws, although I cannot refer back to them since I threw them in the trash.  Pozidriv has a distinctive and clean "star" or "asterisk" pattern, and while it's not easy to see in my photo, the heads I encountered were just badly stripped Phillips.

For a while I had hex bolts in place to replace these, but hex bolts are far too easy to over-torque, and I did over-torque them (curse me).  I damaged the plastic of the inner shell as a result.  Have repaired as best I could with hot glue, have applied wide plastic washers to distribute the pressure better, and have switched to T30 Torx-driven bolts.

The front of the shell is perfectly aligned (centered) now, btw, although the back (on the mudguard side of the wheel) is still closer to the wheel on the right, and I cannot improve this no matter how much I wiggle the shell around with the bolts loose.  I've accepted the current alignment, and it's close enough now that I get about the same amount of rubbing when I transfer a lot of weight to the left side (usually when trying to shift around the right foot to get it in the "right" position) as when doing the same thing on the right side, and there's no audible rubbing during normal riding.  The fact that the shell flexes enough to contact the wheel at all tells me that the plastic around the bolts is probably flexing during normal riding, and that my repairs will degrade over time.  Eventually I'm expecting catastrophic failure leaving the case badly aligned and loose against the wheel/motor, and then I'll probably have to see about getting a replacement shell to transfer all the components to.

[travsformation]

BTW, I know this thread had been dormant for some time, but thought it might be worth tagging @US69 to request that in the future, hex bolts be used to hold the shell in place, as opposed to Philips screws. Upvote or comment if you agree 

[mrelwood]

9 hours ago, travsformation said:

BTW, I know this thread had been dormant for some time, but thought it might be worth tagging @US69 to request that in the future, hex bolts be used to hold the shell in place, as opposed to Philips screws. Upvote or comment if you agree 

As written in the comment right above your’s, hex bolts this size are very easy to over-tighten. They are only holding a relatively thin plastic after all.

I wonder if there are correct size hex bolts available for a smaller hex key? A big 3mm hex driven bolt would be a lot harder to over-tighten.

[svenomous]

The T30 Torx screws I'm using now seem like the best compromise of resistance to stripping vs. potential for over-torquing.