New freeride project - LMX P1

bzhwindtalker

100 kW
Joined
Dec 1, 2008
Messages
1,806
Location
Lyon, France
Hey all, I have a new project!
I start to feel some limits with pedals on my freeride bike and i'm tired of the noise of the transmission and the BB issues. I want a bike that is dead simple and I can crash a lot without breaking a derailleur or bending the BB. My goals are to make a 35kg max 5kw peak 750wh bike with 180mm of travel front and rear, with a geometry close to a trial bike but not quite as low. I will re-use my dirt mtb wheels, with a 3" tire in front and maybe a motorcycle tyre in the rear. I will make the frame with mild steel, 1,5mil thick. The frame will have a double downtube like my previous custom frame. I'm undecided yet for the seat, it could be either a bike saddle or a cutom fiberglass seat/rear muddguard. 14s lipo pack, and probably the blt 800 from goldenmotor with a 18fet on 100A peak. The Mac lawnmower motor could suit this project too. I would like to find a double wide GNG inruner, I like that motor but i don't think it will survive more than 40-50A peak. Any other motor that I should consider? The bike will be geared for 55kph, single stage of #219 chain (1/10 reduction ratio max).
I will try to finish this project before spring.
As for legality issues of making a motorcycle, I don't ride on the streets exepted for transitioning between zones and usualy riding on the campus so it should not be a problem.
 
Looks good but you might have chain clearance issues like I am fighting right now unless you slack the chain a lot like a dirt bike and run a pair of chain guides top and bottom... maybe you had planned this?
 
Well I tink the chainline will be simple enougth to work without chain guides or tensioners. Actually what I am trying to do is a mix between the original blade 04 and the E-tricks :
Blade 04 :
mqdefault.jpg

Etricks
7b969b_d40b21cb6dd942ce0b0add8c011409a2.jpg_srz_920_549_85_22_0.50_1.20_0.00_jpg_srz
 
bzhwindtalker said:
Well I tink the chainline will be simple enougth to work without chain guides or tensioners. Actually what I am trying to do is a mix between the original blade 04 and the E-tricks :
Blade 04 :
mqdefault.jpg

Etricks
7b969b_d40b21cb6dd942ce0b0add8c011409a2.jpg_srz_920_549_85_22_0.50_1.20_0.00_jpg_srz


I have now had the pleasure of riding a e-tricks and it rides as good as it looks, I was going to buy one a couple of years ago but there was no uk dealer. I will be watching how you get on with this one, looking forward to it.
 
In fact I think the e-tricks is a near perfect setup for all types of e-biking , its light, small (with the 20" wheels) , ( they should also do it in 24's or 26" wheels ) , its very strong. neat idea to be able to upgrade/expand the battery pack, the only thing it lacks is peddles which should be optional to make it a true e-bike all rounder, I would rather buy one of these anyday of the week than a stealth ( which is to do with price and looks ) . I still think at 4.5k euro's ( top of the range ) is still very expensive for what it is and should be priced at around 2.5k and 1k for entry level.

edit: http://www.etricks.fr/en/range/etricks-little
 
Yeah I like the etriks a lot too, I never ridden one but it looks like a nice little bike! However it's rather limited with only 2500w and 20"s, and yes I think it's a bit overpriced too...
I stared woking on the frame CAD model, Solid edge is such a pain to work with when you don't have all the modules! I have it for free through my engineering school but I would take solidworks or catia over it if I could!
 
Those monster T are not fitting the bike well at all! Who has a Boxxer or Bomber Forks 3d model?
Lmx frame.jpg
file.php

The frame will fit a 180mm motor. I have a old DD hub that I could convert to a bad ass outruner...
 
Thats what I have in mind with the bike seat, I think it will be simpler and stleathier like this, as bike seat=bike and pit bike seat=ghetto gangster (bad stuff)
LMX26.jpg
 
Found a 24 rear whel but I had to model the tire. I made it slighly bigger than my 3" duro leopard. The swingarm looks a bit too long...
I will try a version with the mx style seat to compare.
LMX2624.jpg
file.php
 
looking good. I hope you are thinking about some rear fender, you dont want THAT part of your body to get sucked into the back wheel ( it hurts,,, dont ask me how I know :D )
 
I agree, maybe a thin bar going from below the seat over the motor sprocket to the lower frame. Most of the stress is from the rear shock... Would be a good way to cover the pants grabber too..
 
gwhy! said:
looking good. I hope you are thinking about some rear fender, you dont want THAT part of your body to get sucked into the back wheel ( it hurts,,, dont ask me how I know :D )
Well yes this does not sound good! I suppose the fender needs to be pretty rigid too?

I usualy have quite a good mechanical feel of things and I did not think once of bracing on this frame, but it's true that a protection plate that would double as a motor support and frame brace would be pretty cool.
 
That's looking very nice! Two suggestions if I may:
1. Look at the swingarm and shock mount arrangement on the e-tricks bike. It is subtly different but is better in two ways. One is gives the shock a much easier time due to the more advantageous leverage ratio which makes the rear suspension work better. Second, it has a more linear response over the total travel, again much better if you're planning to use the travel, i.e. jumps and drops.
2. You'll need to brace the swingarm pivot such as this, but maybe you haven't drawn those kind of details yet:
lyster_2_reduced.jpg
 
I am in talks to get a mac lawnmower motor. I got the idea to use the motor mount as a frame brace, water cutting could make it look cool! A friend will make me a stainless steel battery box to hold the fireworks and magic smoke ;)
 
bzhwindtalker said:
I got the idea to use the motor mount as a frame brace.

If the motor can handle it, that is an excellent idea! Think of the motor as the frame and hang whatever structures you need off there, e.g. pivot the swinging arm on the motor shaft.
 
Hi Adam's

Hi hope that you heal quickly, I like to know if I can use your design for my next ebike project because I have found an Agni 95R motor and your design is about perfect for this project.

Good day!
Black Arrow
 
The healing is going on slowly, can't wait to get back riding. I fixed the rear brake on my blue fr and I'm ready to blast. No prob to use my design as long as it's not commercial! Such a bike with a 95R would be really fun ;) keep me updated on your project!

Adam
 
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