Another LCE930 Build Thread

[mikelikesbikes]

Hey Yall,

Im in the process of building my first EMTB and wanted to share with you all since I found other forum/posts here helpful. I wanted a bike the feels like a trail bike with some extra power for commuting to work threw canyons and exploring on longer weekend rides. I narrowed the choices down to a CEF50 and a LCE930, and settled on the LCE930 due to frame geometry. The front offset is 44mm for the lce930, opening up a lot of shock options were as the CEF50 was 51 and more e-bike specific offsets only.

Next decision was motor voltage... 48v or 36v. 43v did not interest me due to lack of off the shelf expansion batteries available... and just kind of seemed niche. I could purchase a BT F100 or BT F014 in 36v, im not aware of any off the shelf 48v battery for this frame. The bafang options seem robust and based on wattage they likely use good cells. Butttt they come in housings that are heavy and take up volume. I decided to go the 48V route and build my own pack. I went with Samsung 50s 21700 5000mah 25a battery, their current ratings are overkill for the bike, but the price was not that much more and by not running the cells close to their limit im hoping for longer lifespan and more thermal stability. a 2P13S pack will yield 480 Wh and a 3P13S will be 720. Im not sure what route im going to choose yet.. waiting on frame arrival to decide. I bought enough cells to make 2 x 3p13s packs... with the thought of making an additional pack for a water bottle mount for longer weekend ride, and keeping the weekday commute inframe pack as light as possible.

I intended to build a 3k usd bike... and then got carried away on suspension... Here is what i have purchased so far. As components arrive i will update here and try to document the build process to help others, as i found help with the resources here in my purchase.

Frame: LCE930 Medium
Front Fork: Ohlins RXF36 m.2 Trail Air 29 Fork, 44mm Offset, 160mm Travel
Rear suspension: Ohlins TTX22M 2 Metric Trunion Side by Side Coil Shock, 185mm x 47.5, 50, 52.5, & 55mm
Stem: cheap aliexpress
bars: Flat 31.8-740mm"ec90"
grips: cheap and look decent...
Brakes: 4 piston
brake rotors: RT86 180MM
Wheelset: EliteWheels 36mmWX24mmD, F15x110mm R12x148mm, Black Decal, MS 11-12S, 6 Bolt Lock
Motor: M820 48V
dropper post: 860i 31.6x345, CHINA

Ill update the battery build once the parts arrive.
Also id like to thank Jim Lee at light carbon for the help in purchasing the frame and info on builds. picture below is the paint scheme i went with, was instock, looks great and should mean a faster delivery.

 

[Sayonara]

I have the same brakes. They are great but come only with one set of olive and needle so if you want to trim front brake cable as well you should buy extra. Bh59/63 are the ones that fit. MTB Bicycle olive head Mountain Bike oil needle BH90/BH59/SRAM/MAGURA /TEKTRO tubing cut-off oil brake with compatible Shimano - AliExpress 18

Also the brake pads that come with the brakes are not great. These fit and work great. Hope Tech Evo E4 RX4+. Bicycle Disc Brake Pads for Hope Tech Evo E4 RX4+ Hydraulic Caliper. 4 Pairs, Gold Full Metal - AliExpress 18

I also bought this bleed kit and works well with the brakes. I chose the 2023 race edition for the storage box but I guess any of them work. How To Bleed Brake Master Cylinder|hydraulic Disc Brake Bleed Kit For Shimano, Sram, Avid, Magura

 

[mikelikesbikes]

I have the same brakes. They are great but come only with one set of olive and needle so if you want to trim front brake cable as well you should buy extra. Bh59/63 are the ones that fit. MTB Bicycle olive head Mountain Bike oil needle BH90/BH59/SRAM/MAGURA /TEKTRO tubing cut-off oil brake with compatible Shimano - AliExpress 18

Also the brake pads that come with the brakes are not great. These fit and work great. Hope Tech Evo E4 RX4+. Bicycle Disc Brake Pads for Hope Tech Evo E4 RX4+ Hydraulic Caliper. 4 Pairs, Gold Full Metal - AliExpress 18

I also bought this bleed kit and works well with the brakes. I chose the 2023 race edition for the storage box but I guess any of them work. How To Bleed Brake Master Cylinder|hydraulic Disc Brake Bleed Kit For Shimano, Sram, Avid, Magura

thanks for the input on the brakes, i added 2/3 of the suggestions. last link to the bleed kit is broken on my side.

 

[STK]

thanks for the input on the brakes, i added 2/3 of the suggestions. last link to the bleed kit is broken on my side.

Thanks for the tip on Full metal pads. I burn through so many on the eMTB!

 

[mikelikesbikes]

Frame is here!!! I'm very happy with the quality of the paint, fit and feel of the frame. No sharp edges inside, resin looks uniform and all in all great value. My cell phone picture skills dont do it justice, the paint appears to have a matte finish but still sparkles in the light and the stickers seem to change color based on light.

Im still waiting on a few parts but decided to start by test fitting the rear shock, it appears to have pleantly of frame clearance at near full compression (i was not able to get to full by myself as i was afraid of tiping my frame stand over...). Lower bushing is on order for the frame size of m10 x22.2mm and should arrive wed.

The aliexpress shimano set appears to be legit! I stripped the chain of the factory oil with a couple mineral spirit baths followed by acetone and dipped in SILCA secret Chain Blend wax.

I mocked up the batteries and think i can get groups of 6, as of now I'm gonna try to go with the 3PS13 and have a jig printing for a test fit. I should be able to clear the water bottle bolt holes, still pick up factory holes and only be slightly longer than the bafang battery. should be... that is

I'm waiting to build up the frame until I can ensure battery fit, figure it will be easy to test fit the battery first, then route cables and reinstall battery.

Outstanding items:
-M820 is still overseas, waiting on a domestic tracking number
-carbon wheelset is way slower than advertised, i picked up a narrower shimano set to hold me over
-handle bars are mia
-identify a charger, and connector system i like... i want ip67 and if it fits in the stock frame hole that would be great
-build a multiple power source circuit with either a diode or an "ideal" diode setup for easy external battery use down the road.
-assemble first battery pack.
-go riding!

 

[mikelikesbikes]

battery pack is going to be made in groups of 6 cells, i plan to daisy chain down the line to reduce amount of wiring complexity and resistance... Each section will have 2Sx3P with each of the S in opposite polarity... Ill put a better drawing up later after i cad it out. Going to use alignment jigs like this first prototype to spot weld in groups of 6 and then fold the Nickle strip over to attach to the other sections.

For structure i think i will use 2 x 1/8" carbon dowels with fdm braces at each cell cluster of 6... then the usual Kapton / heat shrink process. The arrangement of the cells allows for water bottle cage screw clearance, and i plan to attach the battery pack to the oem mounting points aswell. Plenty enough clearance for cables and ill probably add some foam to help keep the battery pack from rattling around.

6 section

8 section was tight and i would not recommend it in this exact arrangement... with enough finesse it might be possible.

I bought "pure Nickle" strips off aliexpress and was pleasantly surprised! I work in Engineering and had a FIB, SEM, EDS analysis done on the Nickle strip... I did not clean the sample and It appears to be pure and of good quality, the other trace elements (other than Zn) are so low that they could be residue from other tests in the machine and not this strip.

I have not spot welded these yet but think its safe to recommend them. I went with 200um thick by 8mm wide. aliexprss nickle strip

I plan to finalize the battery design after work hours and try to assembly by early next week.. unless the M820 or bars are going to arrive soon then ill push this out to ride!

 

[mikelikesbikes]

Its alive! Im fresh back to mtb, been maybe 6 years since my last mtb was stolen and i started riding road/gravel only as i was busy with life. Super plush, carves great and takes a set with alot of confidence.

The battery pack is a home brew 2170 3PS13, it fits, but is snug. I wanted the cells to be able to expand with heat so i designed the pack to have a 20 tho gap between cells. I spot welded the cells in groups of 6 and then folded into a straight line, fdmed a spine like structure to hold each group of cells and then tieded them together with 1/8" carbon rod. After heat shrinking the pack its pretty sound, only fear is if i take a spill in water as its not water tight.

time to ride and start dialing in the bike!

 

[sandnap]

The final weight is impressive, especially with a 720wh battery. Nice bike!

 

[brbr]

Its alive! Im fresh back to mtb, been maybe 6 years since my last mtb was stolen and i started riding road/gravel only as i was busy with life. Super plush, carves great and takes a set with alot of confidence.
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The battery pack is a home brew 2170 3PS13, it fits, but is snug. I wanted the cells to be able to expand with heat so i designed the pack to have a 20 tho gap between cells. I spot welded the cells in groups of 6 and then folded into a straight line, fdmed a spine like structure to hold each group of cells and then tieded them together with 1/8" carbon rod. After heat shrinking the pack its pretty sound, only fear is if i take a spill in water as its not water tight.
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time to ride and start dialing in the bike!

Nice build! Amazed by the weight as well, with a coil !
I really need to build me battery to replace the Bafang and have something lighter. I guess you don't have huge reinforced tires as well ?
Regarding the battery, it would be great if you could share your 3D designs !

 

[mikelikesbikes]

As requested here is the battery pack info and stls for the plastic 3d printed parts. I want to caution people that working with battery cells can be dangerous, please be careful and I in no way imply my design is safe or easy to build. If i make another battery pack i would refine some things and probably make a better alignment jig for laying everything up to the carbon spine. Do not over constrain the battery cells, they need to be able to swell if they get hot, i choose to use E60 potting compound because i had experience with it and i know it gets soft when warm, next time i would choose a more viscous potting compound with the intent of gluing the centers of the cells together but allowing air at the outer bits. The bms was the largest part of the pack and the trickiest to fit in the downtube, next time i would align it to the pack in the tube before fixing it to the fdm mount with e60.

Parts
39 x Samsung 50S 21700 5000mAh 25A Battery 1860 battery store
1 x pure nickel 200um thick, 8mm wide roll aliexpress
1 x 48" 1/8 od carbon fiber rod mcmastercarr
kapton tape 2" wide mcmastercarr
E60 potting compound Henkel
heatshrink 150mm flat width, 3m length Amazon
charger (untested at this point) amazon
charging port (untested at this point) amazon
bms amazon
6x burn in thread inserts 6mm tall, tapered od 7mm to 6.12mm (had on hand, no link)


all parts where printed on my prusa mk3 with petg and standard infill.
i had to clearance some of the mounts to clear e60 that ran in the previous steps. be carful working with carbon, its dangerous to inhale or get in your skin. I assembled the spine in 2 steps, i put the upper 4 hole mount on, with all the sine sections and let cure overnight, in the morning i put it in the frame and aligned the lower 2 hole mount so all 6 mounting holes would be accessible, marked the position, and removed to fix in place with the e60. I also charged the first cycle with a current limited benchtop supply and with out heatshrink so i could see if anything went wrong before i sealed the pack up. I would not trust the pack to be water tight, i may revise the heatshrink before winter. Do not over tighten fasteners into the cell, get short M5 fasteners.
This probably took me 8 hours to fully assemble, i was having fun and included cad time in that, if you take this on, have patience. Good luck!


print atleast 2 6 cell jigs and square up the cells so the top and bottom are different polarity as in the picuture below. Use a dab of e60 (or more viscous potting compound) in the center to tack the cells together. do not use too much.

next i cut the nickle strips for spot welding. the nickle will weld to the cell metal alot stronger than to itself, cut in a shape that allows each weld to directly make contact with the cell.

assemble the 6 groups of 6 cells (12 groups of 3 stacked 2 high... ><), and 1 group of 3 cells. then when ready to put the whole pack together, use the 2 wide jig to align the cells before spot welding 2 groups of 6 together. (note polarity). solder sense wire in a way that it will not rub on sharp edges, kapton and fold long-wise before adding the next group of 6...

burn in thread inserts and print all the fdm structures needed. fixture in a straight line and e60 in place. i test fit the assembly and decided to overhang the cells above the top mount towards the steer tube for bottom clearance.

final assembly

 

[brbr]

this is what we can called a very detailed feedback! Thanks a lot!
I keep all this in a safe place, and I will think about this, I’ve built a 12s1p pack while I was waiting for Bafang official battery, that was fun but working with cells can be scary !
Maybe a 13s2p would be enough for my needs, I will think about it.
Anyway, thanks again for your feedback

 

[patdam]

Congratulations mikelikesbikes for your job and your feedback. To be honest i'm afraid to doing myself the batterie and taking account of cost of custom made, i prefer purchase it to reconized company.
I find also more better to have rigid cage to solidarise cells.

 

[Hattori-Hanzo]

Amazing thread, lots of great info for anyone looking into building an emtb.

Thanks for taking the time to put this together

 

[mikelikesbikes]

thanks for the kind feedback, I did my first decent ride today, left the house at 81% battery and came home at 32%. 22 miles and 1200 feet of climbing, mostly in B and S+ modes.

At first impression the M820 with stock 48v tune is a very pleasant experience, i prefer it to the Bosch perfomanceline on my trek. Biggest thing i noticed is that it adds to the experience without dominating... the power modes actually work, on the bosch if im not in the fastest mode the motor feels like a generator. Its enough power to climb to the limit of the tire grip, and on flats lets me have fun where i would normally drop speed.

I need to play with my fit on the bike and the riders ability, i want to revise the seating position and get more weight rearward. I found a group of experienced mountain bikers on very nice name brand bikes during the ride in a technical single track decent and was able to stay up with them, if anything my ability was the limiting factor.

I highly recommend the lce930 and m820, id buy this again. Thanks @JimLee-Lightcarbon for all the help during purchase to explain what others have done and what should fit on the frame. Gonna put alot of miles on this rig!

 

[JerryXC]

Where did you buy the motor seperately? Your post inspired me to try and build a 1000wh battery. Great work and insight!

 

[brbr]

Where did you buy the motor seperately? Your post inspired me to try and build a 1000wh battery. Great work and insight!

Check on alibaba, there are a lot of sellers, I bought mine on Changzhou.
For the battery, not sure there is enough room in the frame for such a bike battery

 

[JerryXC]

You posted a picture with 8 27100 cells roughly fitting in there. Maybe its somehow possible. might 3d print the measured interior to see if it can fit and then some cables squeezed next to the bottle holder buldge. If its not possible then maybe 800wh is doable. Im thinking about 48 5500-5800mAh LG cells