E-S LMX 64 Bike Owners

[Cowardlyduck]

It seems like this might be a wider spread issue than we realised.
I also wonder if the throttle settings might come into play?

Hey Adam, is there any chance you can update your Nucular firmware to the latest, tune the motor and PAS, then export your settings and upload here for us. At least then we will have something consistent to go off.

Cheers

 

[Cowardlyduck]

I think I finally figured it out...and of course it was something so simple!
The firmware update reset the wheel circumference down to 2100 or the equivalent of a 26" wheel with 2.2" tire.
According to this link:
https://www.bikecalc.com/wheel_size_math
After setting the recommended 2425 wheel diameter my WOT speed is now 50kph!


So my perception of speed must not be that finely tuned as I didn't feel like it was still actually doing 50kph before, but not it does. :lol:

Anyway, now that I've got that sorted I have a new problem...my belt has started slipping. :|

It started the other day, but I wasn't sure what it was. It seems to be getting worse also. I suspect it might have something to do with the RP7 I sprayed all over the place to stop the squeaking. I sprayed a bunch of degreaser on the belt and that helps for a while, but then it starts slipping again.

It only slips on initial take off and mainly in mode 3. It will do it a bit in mode 2, but it's obviously related to the torque levels.
I played around with accelerations limits and tried reducing my mode 3 down to 150A phase (50A batt) and while it helped initially, it didn't last long before the belt started slipping again even on mode 2 power, 120A phase (35A batt) so it definitely seems to be getting worse.

Is there any substance I can apply to the belt teeth that will aid friction without wearing the belt away?
I have some carbon seat-post friction grease, but it's like greasy sand so I don't think that's a good idea.

Should I just soak the belt in degreaser to remove any residual oils?

Thanks for any replies during this crazy time!

Cheers

 

[Joe]

Now I’m confused. I just took photos of my hall tables. There a lot different as to my LMX cfg listing.
PS. If you are on the March 11th Firmware I have a hotfix file. That corrects the speedo when using data source speed source = Display.
I‘ll Upload it soon.

See hall tables.
Question? Do the hall table get automatically changed when we do the full motor setup? This is the only thing I can think of. I loaded the LMX cfg file. But it now has changed.
PS I run on 0.6 bar. I‘m gonna pump them up to 1.5bar and see what speed I get, just for this test.

 

[Joe]

I was reading about belts. Some say. To stop a squeak. Use a spray, others say. This will only help for a very short while. Then the belt gets slippery. Wash your belt with a degreaser. That might help. I run completely dry. No slipping as yet. Brake cleaner will remove the grease if soap doesn’t.

 

[stingray63vette]

CowardlyDuck - lucky! The one I am working on is 2260 and PAS is still unstable. Assuming Adam is directly involved with LMX from what I can see in the thread. Is it possible that the belt slip as caused by PAS instability that is new to the 11th update? (since my chain would probably also slip with the current issues if it was a belt)

Joe - would also love to compare with that hotfix file. Maybe swapping back over to Display from Controller and then doing Auto-Setup will see my PAS become smooth again.

I do think the Hall changes with Auto-Setup. I loaded the newest official cfg, then did Auto-Setup, then looked at the tables. Different numbers from the March 11th release.

 

[bzhwindtalker]

It is normal to have different offsets, as on the nucular the phases are not identified, it means that from one bike to another you may have the different phase connected from controller to the motor.
For the belt slipping, I would really reccomend to run the belt dry, I think you have a spare?
Best regards, Adam

 

[bzhwindtalker]

yes for a limited time frame only lmx 64 i'm intrested .
what do you think adam do whe have a deal? building bike for competition sezoen 2021.

For frame only I have to check, in any case only L frames are available as kits at this time, as stock on M is low.
Please send me an email or PM with what you need and your adress and I will make an offer.

Adam

 

[Cowardlyduck]

Thanks for chiming in Adam!

The halls offset differences makes sense...to a degree, but what we shouldn't be seeing is differences following a firmware update, or large differences between motors/bikes. If that's the case something else might be going on.

Thanks for the advise on the belt. I will try degreasing this belt and if I can't get it working again, I will switch to the other belt. Glad I ordered 2!

I also wonder if it might be ok to switch to a larger front sprocket? Would 14T equivalent work ok?

Cheers

 

[bzhwindtalker]

Well, making a larger front sproket would make sense for the torque handling, but not for the motor heat. I guess it depends on your use case. That would also require a larger belt, like 1760mm or something similar. 14-100T equivalent with the 116 back sproket would be 16T I'm sure it would already make a big impact on the torque but then the sproket guard would not fit anymore.
I can send you a 3d file for you to try to print it to check fit if you have some free time

Adam

 

[Cowardlyduck]

Thanks Adam!
Yes, can you please share the 3d file for the sprocket.

Is there a slightly larger sprocket size that would still fit with both the current belt size and sprocket guard? Maybe a 13T equivalent?
I don't really want to have to get a new belt or change the guard if I can avoid it.

If I wanted to buy a new sprocket, what would be the type/size I need to order?

Cheers

 

[Joe]

CowardlyDuck - lucky! The one I am working on is 2260 and PAS is still unstable. Assuming Adam is directly involved with LMX from what I can see in the thread. Is it possible that the belt slip as caused by PAS instability that is new to the 11th update? (since my chain would probably also slip with the current issues if it was a belt)

Joe - would also love to compare with that hotfix file. Maybe swapping back over to Display from Controller and then doing Auto-Setup will see my PAS become smooth again.

I do think the Hall changes with Auto-Setup. I loaded the newest official cfg, then did Auto-Setup, then looked at the tables. Different numbers from the March 11th release.

Here's the hotfix file.
This is only for the 11th March firmware. You may need to rename it to Ndisp.bin. The (4) should be removed
Place this file onto your flash card. I took off all the other files and had only this file to load.
Goto.
On-board computer. goto software update. Start. The Nucular logo appears and the top of the screen shows the file loading.
Afterwards, goto, device, nucular controller, goto Data source. goto speed source, change to display and then save.
The rear wheel will show now the speed. Note there is a time delay. After the wheel has stopped turning the speed is still shown for about 6 secs.

 

[stingray63vette]

Here's the hotfix file.
This is only for the 11th March firmware. You may need to rename it to Ndisp.bin. The (4) should be removed
Place this file onto your flash card. I took off all the other files and had only this file to load.
Goto.
On-board computer. goto software update. Start. The Nucular logo appears and the top of the screen shows the file loading.
Afterwards, goto, device, nucular controller, goto Data source. goto speed source, change to display and then save.
The rear wheel will show now the speed. Note there is a time delay. After the wheel has stopped turning the speed is still shown for about 6 secs.

Loaded this on the March 11th firmware that I already had, switched Data Source to Display, and PAS was still blown. Re-did Auto-Setup (again) and now PAS operates perfectly. I do see that 6 second speedo delay.

Note that before I re-did Auto-Setup, max speed was 20mph and it would occasionally read exactly 348.5mph for an eighth second.

Guess LMX will classify the delay as a bug and fix it with a new rollout of March 11th. My current Hall table after Auto Setup again:

[Hall table]
# Hall input = 6
# Step = 0
Square offset = 10
Hall 0: = 0
Hall 1: = 3
Hall 2: = 1
Hall 3: = 2
Hall 4: = 5
Hall 5: = 4
Hall 6: = 6
Hall 7: = 0
Offset fwd 1: = 3
Offset fwd 2: = 4
Offset fwd 3: = -4
Offset fwd 4: = 4
Offset fwd 5: = 4
Offset fwd 6: = 4
Offset bkwd 1: = 0
Offset bkwd 2: = -3
Offset bkwd 3: = -0
Offset bkwd 4: = -2
Offset bkwd 5: = -1
Offset bkwd 6: = -2

 

[Cowardlyduck]

I got around to working on my belt slip issues today.

I removed and soaked the belt in degreaser and disassembled everything leading to a few discoveries.

The front sprocket was loose. The bolt hadn't completely back out yet, but the sprocket was moving around. The sprocket cover was clearly keeping it in there:

You can also see where the movement has worn away at the top cap:


My bearing seals have fallen apart/out. For now I've just jammed them back in and used an extra bit of rubber as a gasket over the top. Does anyone know how to reseat these seals...can I buy new ones...does it even matter, or do I need a whole new bearing?


After I cleaned up the belt and tighten down the top cover again I was hopeful that my belt slip issues might be solved, but nope...still just as bad.

So I took the belt off again, and compared it my other unused belt:

New is on the left, old on the right.
It's a bit hard to see, but there is a noticeable amount of wear on my old belt...enough to make it slip I guess.
Changing to the new belt has solve it...no more slipping.
I reduced my mode 3 to 166 phase amps now as I don't want this happening again. That being said, my belt wore out really fast...I wonder if it was also caused by other factors like the lube I added to quieten it down, or the front sprocket moving about.

Adam also sent me a STL to 3D print a 15T (13T chain equivalent) front sprocket. Thanks Adam!
I test fit it to see if it would fit under the sprocket guard and pleased to say it does:



I think a 16T might even fit also, but then it might be too slow and cause tension problems.

So I will probably get one of the 15T ordered also as I think it might make my worn out belt work again.
I only put about 500km on the first belt.
Lets see how long the second belt lasts with lower power!

Cheers

 

[Allex]

Looks like you have an excessive wear on the motor pulley too.
To reduce the excessive wear on the primary sprocket(and the belt itself) and belt skipping, it needs to be Bigger.

 

[Cowardlyduck]

Looks like you have an excessive wear on the motor pulley too.
To reduce the excessive wear on the primary sprocket(and the belt itself) and belt skipping, it needs to be Bigger.

Thanks Alex. That makes sense... Sounds like I should get/try the 15T then.
Adam is that something you plan to offer or should I look to source one locally?
I wonder how long one printed in PTFE would last? I did try the PLA one pictured above and at first it seemed to work, but I forgot the keyway so it spun out within seconds melting the PLA around the shaft pretty quickly. That was a PITA to get off :lol:

Cheers

 

[briangv99]

Looks like you have an excessive wear on the motor pulley too.
To reduce the excessive wear on the primary sprocket(and the belt itself) and belt skipping, it needs to be Bigger.

...or better yet, same size but made with steel

 

[briangv99]

Looks like you have an excessive wear on the motor pulley too.
To reduce the excessive wear on the primary sprocket(and the belt itself) and belt skipping, it needs to be Bigger.

...or better yet, same size but made with steel

Dug this one out of my parts collection, steel 14t


https://www.out2win.com/catalog/pfeifer.html

 

[Cowardlyduck]

Dug this one out of my parts collection, steel 14t
IMG_20200330_153440_copy_1152x528.jpg

https://www.out2win.com/catalog/pfeifer.html

Well there you go!
If you have no need, I'll gladly throw some $$$ at you for it.
Will it fit though? I have no idea about belts still...are they all the same pitch, etc?

That sprocket looks quite different to my existing one...it looks like it could be too wide to fit under the sprocket guard maybe?

Cheers

 

[briangv99]

Its 8mm pitch, which is same as LMX, but profile may not be right?

It would need to be bored to 14mm, narrowed from 20mm to 12mm and a new keyway filed. All depends if the groove profile is right.

 

[Cowardlyduck]

Its 8mm pitch, which is same as LMX, but profile may not be right?

It would need to be bored to 14mm, narrowed from 20mm to 12mm and a new keyway filed. All depends if the groove profile is right.

Thanks Brian.
Sounds like a lot of effort. They don't look too pricey, so I might just try and source one new...then I can get a 15T while I'm at it to have as a spare or try out when doing some steep climbing.

Measuring up the STL Adam sent me the width (profile) is 16mm total with a 5mm offset from the motor. The bore hole is 14mm, and the keyway is 4mm wide x 2.3mm deep.
Searching around, I can find plenty of almost but not quite matches. They seem either not have the right bore hole size, no keyway, not the right profile, or are not steel.
Any suggestions for where to source these?

Cheers

 

[briangv99]

Any suggestions for where to source these?

No off the shelf options that fit the spec, but a machine shop, like the one that produced your Fighter torque arms, could do a run from a CAD file. Could be expensive for a small production run, but then again replacing 7075 pulleys every 500k isn't going to be cheap.

It may be something Adam is willing to look into.

 

[briangv99]

Any suggestions for where to source these?

No off the shelf options that fit the spec, but a machine shop, like the one that produced your Fighter torque arms, could do a run from a CAD file. Could be expensive for a small production run, but then again replacing 7075 pulleys every 500k isn't going to be cheap.

It may be something Adam is willing to look into.

PS - Pfeiffer Industries, the maker of the pulley in my post, do have a custom pulley request form
https://www.pfeiferindustries.com/custom-timing-belt-pulley-design-form

 

[Cowardlyduck]

Thanks Brian.
That sucks! Had no idea it was that custom.
I wonder if LMX had them custom made though...Adam, can you let us know what the deal is?

Cheers

 

[briangv99]

I wonder if LMX had them custom made though...Adam, can you let us know what the deal is?

Looks like the sprocket is custom made by Adam and looking at the belt picture you posted, the profile appears to be Poly Chain GT, so the sprocket I posted early isn't suitable.



some searching might turn up a suitable sprocket

 

[bzhwindtalker]

Our sprokets are custom made in 7075-T6 because 14T is very small and not readyly available.
If the sproket wear becomes a problem we will look into getting some stainless steel ones made.
We had them sepcially made because 12mm wide is not standard and we wanted to integrate the flange into it.
Adam