E-S LMX 64 Bike Owners

[iacei]

Just found out why I don't get the whole 17Ah from my battery (which is the one from em3ev), it's because the charger from LMX only charges up to 58V and not 58.8V

In one hand it's good for battery life but on the other hand you loose some capacity.

Next up is to see if the 14S6P and 14S7P from em3ev could fit in a way

 

[Mihei777]

Hi Guys. I ve been riding with my lmx64 mostly throttle enduro and cross (no pedaling). I havent use some much different gears and few times i have broke gearshifter when it hit againts rocks.
So decide to remove it. Here is pictures how i did it


I use only biggest gear and it seems to be suitable when pedaling. Also good thing is that rear wheel is now lighter and less parts to broke.

 

[scrambler]

Based on the dimension Brian gave me, I played with the following scenarios for an extended battery inside the frame.

As a One piece battery, It would seem we could do 14S-7P (98 Cells) or about 1,200Wh and may be even 14S-8P (112 cells) or about 1,350Wh, with an optimized pack and a cover (see drawings below).
14S-7P

14S-8P

14S-7P or 14S-8P install

Now we could also break the pack in two pieces. That would allow to place the bottom part first, then plug the top part with the cover and slide that in place on top, instead of having to rotate the whole thing in (see install drawings below)

14S-8P two blocks

In that scenario, I think that 14S-8P (two 7S-8P) or 112 cells for about 1,350 Wh should be feasible.
And 14S-10P (two 7S-10P) or 140 cells for about 1,700 Wh could may be even work.

14S-10P two blocks

Two block battery install

Battery cover rough mockup

Link to the folder with all the pictures
https://1drv.ms/u/s!At3vMAQjaOZLknFVeh7KzoAENbW3?e=vHne1g

Other premade pack one could try if it would go in
ElectroRide 14S-7P measuring 267 x 135 x 79 (middle of page below, 65Amp cont, 100Amp peak))
https://electric-bikes.com/betterbikes/lithium-battery.html
EM3ev 14S-7P
https://em3ev.com/shop/50v-14s7p-rectangle-battery-pack/

 

[TorEddy]

Nice work scrambler!!
These calculations should also work for a 72v battery which would be more interesting for me.
A 20s5p would be a nice battery for those who want power more then capacity (72v, 100 cells and 1260wh).

 

[scrambler]

Also, regarding the higher capacity battery, I think it might be easier and allow higher capacity to run pouch cells. It would just be a matter of finding some that are the right dimensions to fit. This is what I already tried (and failed) when I ordered 14 x 40AH cells with the idea of stacking them accross the width of the frame 11 or 12, then 2 or 3 on top. Unfortunately they were a little wider than advertised so I could only get 10 in across the width and putting 4 on top was just going to be too difficult. These are the cells I ordered: https://www.aliexpress.com/item/32974873177.html
Advertised size is 8*104*345mm, but the thickness is a bit too much to make it work

@Cowardlyduck, I liked the idea to try and find a pouch cell format we could use.

I looked at many sites from various country, and could never get something that would scale and position to reach even 30Ah.
So I made some calculations, and found out that their Ah per Volume appears to be 20 to 30% lower than the 18650 cells (using the 3.5Ah Samsung 35E as a reference)

This means it could be impossible to get even a 30ah battery in there using them unless they make more efficient ones

May be I am calculating that wrong, but here is the calculation I did
Samsung 35E is 18.55 x 65.25 or 17,659 mm3 for 3.5Ah > 0.198 Ah/mm3
Placed in honeycomb patterns that density goes down around 0.16 to 0.18 Ah/mm3 (because of the space between them and the contour of the pack)

The Pouch cell you looked into was 345 x 108 x 8 = 298,080 mm3 for 40Ah > 0.134 Ah/mm3
I looked at many different pouch cells and this was actually the highest density of all, as the smaller cells density is more around 0.11 Ah/mm3

So It seems that even if we did find a size that would allow us to pack them, it is actually unlikely that we could reach even 30Ah.
If that is indeed the case, the dual 14S-5P battery with 35Ah is likely the largest we can make inside the frame.

 

[scrambler]

here are the dimensions we have to work with
....

Brian, can I solicit your measuring skills one more time ?

Could you measure the space between the Rear engine sprocket (the large one) and the rear disk brake (between two sides facing each other). I am trying to see what is the minimum clearance needed between these two for the brake caliper

Also can you check if the wheel is centered inside the dropout or if there is an offset there because of the space needed on the left side for both the disk and the sprocket.

Thank you so much in advance

 

[Cowardlyduck]

@scrambler, nicely done!
I see your point/s and agree with you.
The only other options that haven't been explored are 2170's or stacking the cells upright instead of horizontally.
I think Brian had done ideas about stacking them vertically.
Cheers

 

[scrambler]

I can do some 21700 mockups, but I wonder if these have proven easy to make work in battery packs...
I only remember Luna saying they had huge problems when they first tried to do the Apex battery pack with them. They ultimately gave up and went back to 18650 from what I read.

 

[Cowardlyduck]

Nah nothing wrong with 2170's and they make for fewer connections.
I wouldn't hold much weight to what Luna says given some of the stunts those guys have pulled over the years.
It would only make sense with the highest capacity 5000mah 2170's though.

You should also investigate the vertical layout. At least for the bottom half of the pack, I think it might result in better energy density.

Cheers

 

[scrambler]

Humm...
I just checked the highest capacity Samsung 21700 and I got the following
Samsung 50E: 21.1mm x 70.7 mm = 24,722 mm3
3.6V x 5Ah > 0.2023 mAh / mm3

That is only 2% more than their 18650 35E

So where is the 20% increase in energy density??
Am I missing something here, or the 21700 just have not lived up to their hype??

 

[scrambler]

You should also investigate the vertical layout. At least for the bottom half of the pack, I think it might result in better energy density.

I checked, but when positioned vertically, 4 rows in honeycomb comes to 69mm and 5 rows to 85mm.
If we could do the 5 rows we would gain substantially, but it does not seem to leave much space for wrapping and padding.
If we do 4 rows, then 69mm occupied vs 65mm will not yield in much gain. And it may even be worse, as you need extra space at the top and bottom for all the connections, space that we have in the 90mm box when laying them down, but when standing up, that space will take precious vertical space.

You have built packs, would you be comfortable with a naked pack of 85 mm to put in a 90mm box??

 

[Cowardlyduck]

You have built packs, would you be comfortable with a naked pack of 85 mm to put in a 90mm box??

It depends on whether the gap is on the ends of the cells or the side. If on the side then its no problem, but won't work for the cell ends.

Sounds like you're original layouts with 18650's are still the best options TBH. Thanks again for laying out all out!

Cheers

 

[scrambler]

Hi again,
I would really love the LMX64, but without a derailleur (to each their own, don’t shoot me )

While my ideal gearbox solution would be a Pinion C1.9XR to get the range with less gears, and centered weight distribution, this would require major surgery on the frame, and poses a problem with the torque sensor. I don’t know if any solution other than the Bottom bracket one currently used could be implemented…

As an alternative, I am trying to see if I could adapt a Kindernay IGH to the LMX64 rear wheel, knowing I would probably have to give up the Motor freewheel for fabrication simplicity (unless LMX would have the time and will to offer customization services).

I extrapolated a drawing of the existing Hub from the LMX part picture (below), but I really need to confirm some dimensions, so I can see if an adapter for the kindernay is remotely feasible. Brian was kind enough to already volunteer the chainlines.

I appreciate if anyone can contribute / confirm any of the dimensions in the drawing below.
• Is wheel centered in the 170mm dropout?
• Space between the Motor sprocket and the disc (face to face, and ideally the belt sprocket, but you can confirm the chain sprocket too).
• Thickness of the Motor sprocket (ideally the belt one, but you can confirm the chain sprocket too).
• Space between the outside of the disc and the end of the dropout.
• Caliper extension between disc and sprocket
• Sprocket inside radius / diameter
• Confirm Chainlines

Thank you in advance for any help with this.

 

[TorEddy]

@Scrambler

I was a prototype test pilot for the Kindernay IGH when i had my previous BBSHD bike.
I know the two startup guys of Kindernay here in Oslo, Norway, and i have gone through several iterations of the IGH.
It was pretty solid in the end, but i cannot see how you can integrate the LMX freewheel into that IGH in addition to the disc brake without massive engineering and CNCing.. It woudl for sure be nice though, as it was sweet to not have the derailiur and beeing able to shift gears while standstill..

 

[scrambler]

From my preliminary work (I got all hub dimensions for Kindernay), but without the info I am looking for, I believe there may be a way to do it.

Yes it would require machine tooling an extender for the torque arm, which requires machining the spline profile so it would require access to a CNC machine.
And it would also require machine tooling some fairly simple revolution parts on a lathe to attach the disc and sprocket to the Hub. That is of course if we give up the Freewheel on the engine sprocket which is not ideal, but not a deal breaker either.
We could create a more elaborate adapter that would support the freewheel but that would mean creating a part similar to the one LMX created, but with a larger inside diameter, so it could clear the Hub Torque extender. That would require probably the cooperation of LMX to get details on that freewheel spider piece they made.

I you can get me the info I seek above, I will be happy to share the attempted design and we can determine if it is ludicrous or not
An who knows, may be LMX can chime in...

 

[iacei]

Hi folks,

I made a paper mockup of this pack:

https://em3ev.com/shop/50v-14s7p-rectangle-battery-pack/
Dimensions: 81mm thick. 324mm long, 140mm wide.

and it fits.....kinda.... but you cannot install it due to the side panels of the battery box of the LMX.

with some rework if we coud split the battery in half just the to install it it could be ok but it would be a shame to have to dismantle a em3ev battery....

Other solution that came to my mind...just carry an extra battery on the top bar......Even a smaller one (14s4P) like this one: https://em3ev.com/shop/52v-14s4p-shark/?doing_wp_cron=1602828135.3378510475158691406250

LMX has already foreseen this need: https://lmxbikes.com/fr/partie-cycle/259-montage-deuxieme-batterie.html

 

[ringring]

Hi,
maybe yes:
1. disassemble the electric motor - there will be a lot of space
2. permanently install the battery
3. mount the electric motor

 

[hut8]

I've been reading this discussion with interest and excitedly ordered my LMX64 in early September.
Unfortunately, LMX don't ship complete bikes to the USA so I ordered the frame kit and I have been gathering all the parts needed to complete the build. Also ordered the belt kit which I believe is now fully developed to a reliable robust solution.
To avoid a costly divorce, I sold my 2 other (heavy hubmotor) Ebikes to make room for the new arrival which in hindsight now seems a little premature.
Still no shipping notification after 38 days and now I have been with without an Ebike for over a month and suffering withdrawal symptoms
I know I need to be patient especially with the global pandemic going on, no complaints to LMX (except maybe they could be better at providing updated shipping estimates) but I am itching to get this build going and get out on the trails.
Anyone else awaiting shipping of their ’64? Anyone stateside taken delivery recently?

 

[iacei]

Hi,
maybe yes:
1. disassemble the electric motor - there will be a lot of space
2. permanently install the battery
3. mount the electric motor

Interesting thought, I guess I will try this Winter

 

[scrambler]

Hi folks,

I made a paper mockup of this pack:

https://em3ev.com/shop/50v-14s7p-rectangle-battery-pack/
Dimensions: 81mm thick. 324mm long, 140mm wide.

Did you try a mockup of the ElectroRide I mentionned in my post above it is a bit smaller at 267 x 135 x 79

 

[iacei]

Exactly what I was thinking about too...I will try

But can they ship to EU?

 

[scrambler]

Exactly what I was thinking about too...I will try

But can they ship to EU?

No idea, and I don't even know if they are reputable, I find it strange they are that much smaller, I would want to see pictures of the pack being built with a tape measure next to it...
It is also expensive for such a small gain in capacity...

 

[iacei]

Hi,
maybe yes:
1. disassemble the electric motor - there will be a lot of space
2. permanently install the battery
3. mount the electric motor

After looking again and making a new cardboard mockup, I think that even with the motor out it would be impossible to slide the battery in.

Next step: trying the Electroride one.

 

[Cowardlyduck]

About 7 years ago I first discovered this spot on my Fighter.


Revisited it today on my LMX64, which rides so much better!



It's developed a creaking sound though which I couldn't quite pinpoint, but only exists when the motor is turning. I recall this being an issue previously for others. Was it the front belt sprocket?

Cheers

 

[briangv99]

About 7 years ago I first discovered this spot on my Fighter.
Photo0395 (Small).jpg

It's developed a creaking sound though which I couldn't quite pinpoint, but only exists when the motor is turning. I recall this being an issue previously for others. Was it the front belt sprocket?

Beautiful spot CD, love riding that trail.

I think the clicking others were getting was from the woodruf key coming lose?