LMX P2 : Freeride trials motorcycle frame development

I really liked your vids years ago.
Can you please put some pedals on the bike so I can buy one. I don't have a truck to put a dirt bike in to go ride in some ORV park. Please please make a middrive frame with pedals so I can ride around at 20 mph then let it rip when I'm away from people.

^ nailed there is a theme here Either way congrats on cool product.
The vids are good but should use a gimble. Also add a dash with speed and G's using some of the common motorsport apps.

StinkyGoalieGuy said:

bzhwindtalker said:

On a side note our solderless 18650 pack in the 81 is doing great so far, very promising for the future.

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Please give more details on that solderless pack. And when will it be available to purchase?

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We need some more testing with the latest improvements but if you are interested we can set you up with a beta unit at beta price in a few weeks. What config would you be interested into? we have a 10S6P and a 8S10P (to be used 2x as 16S10P) config ready for production.

it would come pre-wired with BMS and connectors, you only have to install your own 18650 cells and screw the two halves of the pack together with a few M5 CHC.

macribs said:

I guess KMX has a special bike with pedals the 81(?) or something? But giving the option for people to choose pedals or pegs might broaden the customer base.

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Yes I think the 81 would suit a lot of people asking for a 161 with pedals. The 81 is a bike you can actually pedal with 9 speed drive train (in the future 10 speed with cassette). Weight depending on setup can be from 23 to 29kg. Also with the latest developments we can fit 16S6P inside the frame.

Our own bike is programmed for 1600w peak to go with the speed pedelec laws in EU, and I can tell you it is a very fun bike even on 36v/40A. For now our recommended power is 3000W or 50A before we upgrade the motor/sproket link. We noticed some damage to the axle when doing 120A peak on 36v, that is why we do not reccomend over 50A yet. But the motor, drivetrain and frame can take a lot more when we will have the solution for the front sproket implemented.

We delivered 6 kits so far, two more from the first batch are shipping as soon as we receive more 219 chain.



I undertand the "pedals for show" deal, but we worked hard to bring to market a bike where motor and pedalling can be used with good efficiency that I can not give up so easily on the pedal 161.

pics of some of our customer's lmx81 also :

What do you think of Belt drive, is it possible to use with power of 50A?
I cannot stand the chain noise, I have been waiting forever for a silent belt solution. I will buy a bike from you once see this implementation.
Here is Grace RN1 belt solution with 10-15kW


I have seen floating belt drive covers - this is perfect for mud protection

Belt drive is a no go for serious offroad, plus it needs a concentric design or swingarm mounted motor to work. We could implement it on the 81 with the tensioner and freewheel but we only have max 15mm available for a belt, that will be nowhere enough width to reliably transmit 3000w.

On the other hand we can provide a pedal+hub motor version of the 161 now, and cheaper than the regular frame kit as we will not provide the motor, transmission and back wheel.

bzhwindtalker said:

Belt drive is a no go for serious offroad, plus it needs a concentric design or swingarm mounted motor to work. We could implement it on the 81 with the tensioner and freewheel but we only have max 15mm available for a belt, that will be nowhere enough width to reliably transmit 3000w.

On the other hand we can provide a pedal+hub motor version of the 161 now, and cheaper than the regular frame kit as we will not provide the motor, transmission and back wheel.

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I vote to keep the mid drive but with pedals. there are too many hub motor high power bikes to complete with in the market now, and they are too heavy.

[youtube]5-dFz1vzNLQ[/youtube]

Video of our 81 on 36v/1600w peak in action, I did a 2.5H ride on 650wh
The frame is well balanced and the suspension handles this kind or riding no sweat. Next I need to check some big jumps

bzhwindtalker said:

StinkyGoalieGuy said:

bzhwindtalker said:

On a side note our solderless 18650 pack in the 81 is doing great so far, very promising for the future.

Click to expand...

Please give more details on that solderless pack. And when will it be available to purchase?

Click to expand...

We need some more testing with the latest improvements but if you are interested we can set you up with a beta unit at beta price in a few weeks. What config would you be interested into? we have a 10S6P and a 8S10P (to be used 2x as 16S10P) config ready for production.

it would come pre-wired with BMS and connectors, you only have to install your own 18650 cells and screw the two halves of the pack together with a few M5 CHC.

Click to expand...

I would be happy to help beta test two of those 10S6P units.
1) Can I get it without the BMS? I prefer to do my own cell monitoring with a cell-log and use an RC charger.
2) Can I fill it with just 4P if I have to and leave some spaces open? I know I will obviously have lower current capabilities and some wasted space.
3) What would be the cost of each beta unit without the BMS? I'm in the United States.
4) Do you have any pictures?

This 219 chain does not seem to have free floating rollers like regular bike/motorbike chains. This means faster wear and more noise.
Is it possible to use some kind of heavy duty BMX chain on the motor side, have you guys tried it?

hello, BMX chain has a pitch of 12.7mm wich makes it impossible to get big reduction ratio with it. The chain used here is KMC branded kart chain. We think the noise comes from the 12T laser cut sproket. They are cut from 12mm steel so the geometry is not very clean.

thumbs up for 219er chain. It is optimal for that purpose^^

I think I found the main issue with the sprokets, we got them cut from a parametric model I did, but for some reason I had the pitch at 7.7 instead of 7.774

I machined a sproket on the CNC router to test it out and the updated model geometry seem to reduce the noise quite well! Also the first successfull steel part machined on our small machine! 6mm cardbide and 4mm HSS

161 with pedals?

I have to order a 120mm fat bike crankset to try it.

Would you guys consider a drivetrain that would not compromise reliability or performace if it only alowed pedalling up to 10km/h or so?

Thinking freewheel on the motor axis, 38-7t then 12-94t to the back wheel effective speed at 80 rpm crank : 6km/h

StinkyGoalieGuy said:

I would be happy to help beta test two of those 10S6P units.
1) Can I get it without the BMS? I prefer to do my own cell monitoring with a cell-log and use an RC charger.
2) Can I fill it with just 4P if I have to and leave some spaces open? I know I will obviously have lower current capabilities and some wasted space.
3) What would be the cost of each beta unit without the BMS? I'm in the United States.
4) Do you have any pictures?

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Hi, We can ship without BMS, Do you need balance wires?
We can do specific ones for 4P I think, it will be much better for assemby. Polulating only 4p/6p is also possible but not ideal for safety as you would have exposed nickel strip where you do not have cells.

For beta units I have to check total costs but probably around 30$ ex VAT per 10S4P + ship
They will be machined in lexan for the flame retardant and heat deflection caracteristics, plus you can see through to check for any assembly issues. Our prototype was in PA6 but it is quite hard to machine with small diameter mill.

bzhwindtalker said:

I have to order a 120mm fat bike crankset to try it.

Would you guys consider a drivetrain that would not compromise reliability or performace if it only alowed pedalling up to 10km/h or so?

Thinking freewheel on the motor axis, 38-7t then 12-94t to the back wheel effective speed at 80 rpm crank : 6km/h

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I think speed shouldn't be a factor, mainly for showing purpose mentioned above. I only pedal my bike for few seconds during start up or ride home if electronic part screwed up. For a single speed set up, I assume no one expect pedaling to speed ?!

BCTECH said:

I assume no one expect pedaling to speed ?!

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+1

bzhwindtalker said:

StinkyGoalieGuy said:

I would be happy to help beta test two of those 10S6P units.
1) Can I get it without the BMS? I prefer to do my own cell monitoring with a cell-log and use an RC charger.
2) Can I fill it with just 4P if I have to and leave some spaces open? I know I will obviously have lower current capabilities and some wasted space.
3) What would be the cost of each beta unit without the BMS? I'm in the United States.
4) Do you have any pictures?

Click to expand...

Hi, We can ship without BMS, Do you need balance wires?
We can do specific ones for 4P I think, it will be much better for assemby. Polulating only 4p/6p is also possible but not ideal for safety as you would have exposed nickel strip where you do not have cells.

For beta units I have to check total costs but probably around 30$ ex VAT per 10S4P + ship
They will be machined in lexan for the flame retardant and heat deflection caracteristics, plus you can see through to check for any assembly issues. Our prototype was in PA6 but it is quite hard to machine with small diameter mill.

Click to expand...

10s4p would be great. $30 sounds very reasonable. Depending on what VAT and shipping come out to, I would take two of those. If you can easily add balance wires, that would be great.

Any chance you could make something similar for A123 M1 cells? An 8s3p or 5s3p would make for a good high current pack even though the capacity would be small.

So did I understood that correct? You have build some battery boxes which are already connected, where you just have to put some cell into without even having to weld them together?????

Yes, we have a proto unit in test for a few cycles, also with high discharge static test on the bench. Still a few details to check for ease of installation and performance check but so far so good

Will you sell only the weld less setup to make my own battery pack? Asking because it is getting harder and harder to have actually cells shipped here. Atm it seems local pickup of cells even at a premium is the only way to get cells without all the li ion crazy.

@Macribs Oh really? Since when is this so? I buyed my cells from nkon.nl and there were no problems with that.. Did I miss something?

nkon got the needed paperwork and certificates to ship as dangerous goods? Or maybe you where just lucky? I hear from other people (not specific to nkon.nl) too that some shipments are clearing but also some battery shipments get stuck do to wrongful paperworks or incorrect declarations and at best get returned to sender but most likely are destroyed as dangerous goods.

I will contact them and see if they can ship to norway also. They got decent inventory and ok pricing. If they are certain parcel will arrive without problems I will give it a go with cells from nkon.

both bikes are looking awesome!!

macribs, it should be no problem if you buy single cells (no matter where).
It normally starts to get complicated above 100Wh from what i know. If the manufacturer likes to ship packs larger than that, he needs to make a certification. The manufacturer than can pack it into a normal parcel with a "LiIon Sticker" and "flammable, dangerous stickers", and ship it normally as other goods.