LMX P2 : Freeride trials motorcycle frame development

[madin88]

bzhwindtalker, can you tell us what kV this motor has and the length of stator?
i have lost track about this motors because there are now so much different available..

 

[recumpence]

My first ebike had "motor plates" that bolted to the rest of the frame. Very similar to yours. I had a lot of creaking and flex noise from that design. I only used 1/4-28 bolts but I used a lot of them thinking it would be fine. This years re-design is different and so far, quiet. Just waiting for winter to end so I can see how it works out.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=52793&start=25

Looking at y our design, the creaking noise is almost certainly related to the mount screws to the motor housing, not the many screws attaching the frame sections together. That would be my guess.

Matt

 

[Joe T.]

My first ebike had "motor plates" that bolted to the rest of the frame. Very similar to yours. I had a lot of creaking and flex noise from that design. I only used 1/4-28 bolts but I used a lot of them thinking it would be fine. This years re-design is different and so far, quiet. Just waiting for winter to end so I can see how it works out.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=52793&start=25

Looking at y our design, the creaking noise is almost certainly related to the mount screws to the motor housing, not the many screws attaching the frame sections together. That would be my guess.

Matt

The noise would be less if I were driving off the motor alone. It came from the twisting of the frame while I was pedaling and torque off the handle bars. I sprayed oil on all the joints and the noise went away. (for a while at least)

 

[bzhwindtalker]

some bling

[https://scontent-ams.xx.fbcdn.net/hphotos-xfp1/t31.0-8/p640x640/11021354_10153149393504617_8133725406349843310_o.jpg/img]
[img]https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-xpa1/t31.0-8/p640x640/10960129_10153149393244617_9080669049343305565_o.jpg

 

[brooklands]

Still waiting desperately for the announcement of the date of sale...

...or a test ride

Looks very nice!

 

[morati]

Still waiting desperately for the announcement of the date of sale...

...or a test ride

Looks very nice!

+1

 

[Allex]

Really looking forward this frame. But one detail got me worried. Where will the crankshaft be?
If you want to pedal or yet alone sit on the bike comfortably the pedals need to be in front of the seatpost.
Some of the e-frame makers have failed with this. Please, please let this one have the proper alignment.
Look at the "SB" section:

 

[up0]

Drool!
I can't wait for this to be released into the wild!
Looks like amazing work by Lucas!

> If you want to pedal or yet alone sit on the bike comfortably the pedals need to be in front of the seatpost.

Hmm, good point!
Looking at the picture on FaceBook:

I also scratch my head....
But from everything I saw of Adam's work so far, he usually puts a lot of thought into the geometry.
Lets see what his thoughts are.
Cheers,
Ulli

 

[recumpence]

As one who has done a little frame building I can tell you this is a really nicely laid out frame. It does look like the bottom bracket is a bit rearward. Of course, all that would be needed is moving the seat back a couple inches if needed.

So, anyone else notice this picture is a mirror image? Not only are the cranks backward, but the lettering on the mill behind him is backward.

There is a popular cereal brand near us that has the same kind of image on the back of their cereal box. We got into quite a conversation at our house about it.

Matt

 

[Allex]

Looking at the picture now, the motor should be at the back and the crank shaft in front of the motor.
Its hard to judge by the picture but it looks like you have to move the seat quite a bit back if you want to have a normal position.
Anyway, I really hope that this is not the case! We need to see the frames profile to be sure.

 

[r3volved]

Looks like he's already planned on it located behind the bb. Keep your panties on

 

[bzhwindtalker]

Hey I did not reverse this picture haha you guys did :lol: we will probably need to make a new longer seat subframe, but the final product will have the seat subframe adjustable (+- 25mm). Keep in mind this is the prototype frame, used to get the cad right on. It will be rolling at least on pedal power next week. For availability, we need to setup production in India and especially custom rear hubs.

 

[up0]

> So, anyone else notice this picture is a mirror image?

Sure, I have mirrored the image so it would be more easy to compare to Allex white schema-picture above
No big secret behind it.

> but the final product will have the seat subframe adjustable (+- 25mm).
> Keep in mind this is the prototype frame, used to get the cad right on.

Ah, I had thought so - Thanks for explaining/confirming!

> For availability, we need to setup production in India

Ouch, that sounds like we will not have this frame in our hands by this summer :-(
When I look at similar projects it might be the summer of 2016?
Do you have any thoughts to share on timeframes?
If it is 2016, I might look at a temporary solution for this year.

Thanks for a tip!
Ulli

 

[efMX Trials Electric Freeride]

bzh,

as always, really love the bikes, videos, and design progression!..

but while the bike is still prototype and testing..

do you think it may be possible (or might you consider to run the motor chain on left bike side via a davinci drive style brake adapter???

left side motor chain (via davinci drive) would allow use of common dh mtn bike rear hub with no special rear hub required.. and "off the shelf" dh rear hub use could help shorten production time, money, parts sources needed, etc..

left side motor chain with davinci drive would also allow for full range of close ratio rear pedal gears using modern lightweight dh bike components on the right bike side.. opposite the left hand motor drive.. this would also help avoid cross chain interference in the event of a chain break, mechanical, etc..

anyways,, looking good and really looking forward to testing!..

8)

edit, example: http://endless-sphere.com/forums/download/file.php?id=114784

Hey I did not reverse this picture haha you guys did :lol: we will probably need to make a new longer seat subframe, but the final product will have the seat subframe adjustable (+- 25mm). Keep in mind this is the prototype frame, used to get the cad right on. It will be rolling at least on pedal power next week. For availability, we need to setup production in India and especially custom rear hubs.

 

[bzhwindtalker]

We went for this design because it was the simplest option to integrate dual freewheeling. We could have fitted a freewheel to the motor but it would have limited reduction radio and torque handling. As we use a 100mm BB we need at least a fat bike hub in the rear (170mm spacing). If the proposed setup does not work out, we would only have to switch two bearings and the rotor to make it letf side drive and have the full 8-9-10 gears on the other side. But we use #219 chain wich is wider than bike chain so the disc+sprocket on the left side may be a tigh fit.

 

[bzhwindtalker]

Anyways, thanks for the heads up on this, always good to be challanged on design and concepts

 

[scorpionice]

Hey Bzh you haven't answer the question regarding the type of motor you're using. Is that size of a big block GNG or the small one? + one here on waiting on the production.

 

[efMX Trials Electric Freeride]

bzh,

sounds good.. every design has some compromise..
but i thought the motor rear chainring was fixed at the hub??
won't high motor power soon break the freewheel???

even fat bike hubs (150mm) and fat bike multispeed hubs (170mm)
should be easier to source than produce (esp as they become more popular)

as for the brake spacing with left hand drive..
all the disc bikes i have could move the rear rotor about 10+mm left before any frame contact..
then the caliper could be centered on the rotor by using a direct post mount
or a brake caliper adapter that mounts outside the frame instead of inside the frame brake mount..

We went for this design because it was the simplest option to integrate dual freewheeling. We could have fitted a freewheel to the motor but it would have limited reduction radio and torque handling. As we use a 100mm BB we need at least a fat bike hub in the rear (170mm spacing). If the proposed setup does not work out, we would only have to switch two bearings and the rotor to make it left side drive and have the full 8-9-10 gears on the other side. But we use #219 chain which is wider than bike chain so the disc+sprocket on the left side may be a tight fit.

 

[madin88]

Hey Bzh you haven't answer the question regarding the type of motor you're using. Is that size of a big block GNG or the small one? + one here on waiting on the production.

i believe the motor is from here: http://cztopwin.en.alibaba.com/productgrouplist-800331383/motor.html

 

[bzhwindtalker]

Some more progress

 

[sn0wchyld]

Some more progress

looks great mate, and im incredibly jelous, ive been working on my own custom frame for probably 2 years now, and still haven't gotten it off paper yet. You guys work damn quick!!

 

[bzhwindtalker]

Thanks sn0wchyld ! working in team certainly has advantages

more pics, notice how thin is the frame (only 80mm)

 

[Allex]

Any chance of having belt drive on this thing? I really don't like the noise of 428 Chains and similar.
Edit: guess not, due to particular swing arm design..

 

[efMX Trials Electric Freeride]

one can see from the new pics that indeed the cranks are currently behind the seat..
that would not be ideal for pedal input (but i expect it will be corrected before production)..

Looking at the picture now, the motor should be at the back and the crank shaft in front of the motor. Its hard to judge by the picture but it looks like you have to move the seat quite a bit back if you want to have a normal position. Anyway, I really hope that this is not the case! We need to see the frames profile to be sure.

 

[brooklands]

one can see from the new pics that indeed the cranks are currently behind the seat..
that would not be ideal for pedal input (but i expect it will be corrected before production)..

Looking at the picture now, the motor should be at the back and the crank shaft in front of the motor. Its hard to judge by the picture but it looks like you have to move the seat quite a bit back if you want to have a normal position. Anyway, I really hope that this is not the case! We need to see the frames profile to be sure.

I would not care too much about the position of the BB. If you want to use the bike as a commuter bike this might be a problem. But the intended use of this bike is freeriding. And while freeriding, most of the time you are standing on the pedals. The only purpose of the seat is not to sit and relax but to bring some pressure on the wheels when cornering. And the closer it is positioned to the handle bar the more weight ist transferred to the front wheel. (Same reason why you sit almost on the tank when cornering with a MX bike).

Check the position of the BB on a normal DH bike:

It is also behind the seat and I guess it is meant to be like this and not a design failure