formal introduction

[Lenk42602]

hello to all - i have been lurking for a while, early august. attached pics of my version one ebike. already working on v 2.0. This one is a 48v 5304 with sla batteries mounted in main triangle. Great fun. I am convinced that my future lies with light electric vehicles. Every single person that has ridden it has had the same reaction - disappear over the horizon, return too many minutes later with tears streaming down their eyes, and a grin ear to ear. That exilaration is what initially brought me to cycling. Became burned out on cycling, but this has rekindled my love for garage engineering.

V 2.0 is based on a GT LTS-5 chromoly full suspension design, 48volts, lithium battery pack, 5305 motor. I was going to take a run at 72 volts, but after consisdering the overall design, application, and most importantly power requirements to overcome drag coeeficients over 38mph, i decided to just keep e bicycle v 2.0 just that - an e bicycle.....

Have been faithfully riding this on my 16 mile commute to work.


relocating batteries in the main triangle makes a HUGE handling difference.


I was quite a "hardcore" cyclist - rode across the country on a solo tour (towing a trailer) in 2000. That trip pretty much extinguished my desire to pedal a bicyle anymore. Tried motorcycling several times with several different motorcycles, but they never really elicited "the grin" like bicycles, and now e bicycles.
Anyways, I am thinking of R&D ing these kits for a year, using for primary transportation and potentially buying an old bike shop late next year where I can use the shop as a platform to begin selling/installing these kits. I am so sick of the more, more, more mentality. Want to be able to work with my hands again, provide a product and service that I am passionate about, and do so while helping the environmental challenges we face. Hello to all, and thanks for a great site!

[D-Man]

Cool battery box and bike. What size sla's did you fit in there? Got a picture of the batterys with the side cover off? I assume its a side cover and the batterys aren't upside down. Good job.

[fechter]

Welcome aboard!
Another person has discoverd the "EV grin". It takes a long time to wear off, if ever.

Great build, I love the ammo can, but I would have looked for something that contained live rounds, not blanks

I can't wait to see V2.0.

[knightmb]

I like the battery box, very clever design. It can probably hold a lot of SLA, plus keeps the balance and center of gravity. Just imagine later when you can upgrade to another battery technology, you'll already have the space for it. Except it might be lighter

[CGameProgrammer]

The frame is definitely a good place for the weight. I used to have 55 lbs of SLA on a rear basket in addition to the controller and rear 5303 (this is what my avatar shows), and steering was very squirrelly and nerve-wracking. Moving even just some of the weight to the frame makes it track much better and more confidently.

Definitely interested in seeing v2.

Bicycling cross-U.S. is pretty hardcore, but boring. I used to bicycle when I was a teenager, going on 2-4 hour trips every day, and it was a chore. I did it to explore but the act of riding a bike was not fun compared to rollerblading or skateboarding. But it sure is fun when you don't have to pedal, at least not just to cruise.

[Lenk42602]

Cgame, The problems with all the battery weight over the rear wheel at high speed are definitely not confidence inspiring.

The batteries are 12volt, 12ah B&B's. The dimensions of each battery are what eventually led me to the ammo box. Considering the narrowest configuration, this size ammo box is a perfect fit with very tight tolerances running the length and height. Regarding width, I narrowed the box by about 1.5 inches. This allows for the width of the batteries plus about an inch which gives me enough area inside to stuff the wiring, 50 amp fuse, ignition switch, etc. I was orginally going the narrow the box and reweld, but access inside the box is much easier throuth side via screws. The lid is not used.

When developing a design, the challenge was in trying to satisfy two different needs for the relocation of the batteries in the main frame with one system:

1. Creating a "subframe" for the batteries
2. Creating a "case" to cover the batteries

I was trying to figure out how to do this with one system that was simply bolt - in. I could not come up with a suitable design, so I began to consider how I can build a tray that the batteries rest on, with a case surrounding the batteries that hep secure them from fore/aft and up/down movement.

If you look closely, you will see that I modified an old rear rack - cut the leg to frame attachments off, fabricated some brackets out of flat stock that mount to the water bottle bolts and into the bottom of the rack. This serves as a solid battery tray, and the ammo box a solid case which is attached to the battery rack, and frame via band clamps.

V 2.0 will use be using some sort of vaccum formed abs or fiberglass casement, potentially incorporating the modified - rear rack- battery tray set up. All very solid in V 1.0 so far, just looks a bit industrial.......

[D-Man]

Are those stock handlebars? Where did you get them? Looks like you could make a dashboard with gauges with that type of design.

[Lenk42602]

those are motorcycle handlebars - off a suzuki dr250. cheap carbon steel. very wide and comfortable... definitely a lot of room for guages

[TylerDurden]

Damn. That's a brick-shithouse.

Lessee... 50lbs in batts/controller, 20lb motor, 25lb bike, plus rider: you might wanna horn... anything in your way is dead meat.

[xyster]

And a brilliant use of hose clamps, I might add.

[Lenk42602]

ha! that's a 23" 4130 chromoly frame from bike nashbar, EASILY close to 7 pounds! Just the frame! Wanted it to be bombproff as my daily commuter. It is a big, bad ball of steel once it gets moving......I kind of feel like a trucker when I get on it....with a full face helmet....

[knoxie]

Hi

I like it!! it really does say F*ck You! in many ways, its got a military edge to it as well!! great stuff, those bars are a great Idea, for gauges lights etc, good luck with the shop as well.

Knoxie

[Ypedal]

Yes sir !!!.. good job !

Single speed rear = good. ( and really.. all you ever need as long as you have juice left !! )

Keep it up !, looking forward to V3 !

[Doctorbass]

Welcome Lenk42602 !

Welcome to the 5305 BRUTE club

at 86V, this beast is simply amazing!

I hope you have the rear version for your V2 ?

Doc

[Lenk42602]

it is a single speed rear - but I am running double rings up front - a 48t big ring and a 38t small ring.

I modified the pawls inside an old XTR front shifter, changing from a three speed to a two speed front shifter.

High. And low.

The 38t has been good for "walking" the bike when cafe hopping downtown, no juice. The 48t ring is good for pedal assisting the motor on the steepest hills around here at full speed. Otherwise, the pedaling i do is just confuse and disorient the enemy.......

[Lenk42602]

thanks doc, but I am only running 48 volts on V 1.0. Version 2.0 is definitely getting the rear wheel set up, however, I can't decide between the 5303 or the 5304. Do intend on lithium, so I plan on losing about 20 or so pounds from the total e bike weight.

[Ypedal]

Suggestion no 1 = 20" rim !

[Lenk42602]

gt (V 2.0) has no rear disc mounts....

[efreak]

welocme

this is exactly what I have in the works and the center mount is identical to that an dafter seeing
these pics today i know i am on the right track specially with the voltage for the 5304 fro my 20 25 km commute.


Why the brute for v.2??

how about 5302 or 3?


v.2 for me is a dual suspension which doesn't allow for a center mount like this one so a lithium pack either on a rear rack but brought around to the front but attached to the seat post or a saddle bag style smallish enough to go over the center bar.
not a lot of room on a bmx style to put a big pack although i love the back pack with the long line yo the controller just unplug and LOCK and walk away ( I am so scared already about LOCKING and stolen stufff like that)

nice really nice thanks

efreak

[Lenk42602]

VERSION 2.0 - frame stripped & repainted the post apocalypse colors......

In the matrix........


Down the rabbit hole.....

Rear linkage close up. Wish this thing was disc, but v brakes will have to do....


More details to follow. Headset and other parts will be forthcoming over the next few weeks. Will document the build process..... For those of you running 20" rear wheels (xyster,ypedal,etc) what do I really gain versus a 26"? I realize it is gearing, just trying to weigh the performance gains versus cost of retro fitting a 20" rear wheel braking system. It can be done, there are disc adapters and v brake lowering plates available. just want to weigh it all before i have these parts in my hands....

[xyster]

For those of you running 20" rear wheels (xyster,ypedal,etc) what do I really gain versus a 26"? I realize it is gearing, just trying to weigh the performance gains versus cost of retro fitting a 20" rear wheel braking system. It can be done, there are disc adapters and v brake lowering plates available. just want to weigh it all before i have these parts in my hands....

Nice work.
Versus a 26" wheel, a 20" wheel gains you ~25% more thrust (like torque but includes the effect of gearing), at the expense of ~25% lower top speed. It's a simple wheel size ratio thing. You can compare graphs of the effects on the hubmotor sim:
http://www.ebikes.ca/simulator/
For maximum efficiency, range, and acceleration, single speed systems like most hubmotors should be designed to go no faster than the top speed on level ground you think you'll want to ride. This top speed can, of course, be increased by increasing voltage without sacrificing power or system efficiency. Increasing top speed by using a wheel that's bigger than you need saps both acceleration/hill climbing power and system efficiency.

And smaller wheels with shorter spokes are in my experience sturdier.

[Lenk42602]

thanks. that simulator is pretty neat. i get it. since I have your attention, can you explain to me what exactly determines how much torque (thrust?) a particular hub motor generates? I am familiar with ICE theory, and have only begun to understand the internals of these hub motors. Windings?

I think I am sticking with lith 48 volts, 5303, and 26 wheel. With my current terrain, I really do not have too much in the way of hills. The few I do I can drop down into my lower gear and actually pedal.

Keeps it a little bit bike....... And fun when I can run wide open....

Len

[Lenk42602]

xyster, reading more on the link you sent regarding hub motor design. cool site. saw it before but never really married intellectual theory to application back then....

len

[Ypedal]

Small wheels and high voltage are a winning combo in the Brushless Hub motor world.

Using a smaller wheel allows more leverage and quicker speed adjustments, peak power is used for less duration when you accelerate.

High voltage makes the motor run smoother, and allows similar Watts at lower Amps..

ex:

72v x 20 amps = 1400w ( Peak )
36v x 40 amps = 1400w ( "" )

The only good thing large diameter rims have over small wheels is gearing choice, it's easier to setup a regular bike to pedal assist at 40 km/h if you have larger wheels.

But depending on your goals pedals may not be required much !! lol

[Lenk42602]

Hello Folks,

Thought I would post some progress pics of the V 2.0 build. The platform is just about complete. Installed headset, fork, stem, moto handlebars, seat post, bottom bracket, replaced rear elastomer shock, regreased all pivot bushings.



Oh and in case you were wondering about the disco-meets - Tron finish, I bought some 3M Scotchlite auto-grade vinyl reflective material for the fork legs. My GF was watching me ignore her (working on the bike) and suggested I do the whole frame. More I thought about it, the more I liked the idea of really being lit up at night. Probably be a few ground - level ufo sightings in Oakmont once I get this baby rolling!

The reflective material is really cool - looks black during the day. Here is what it looks like without the camera flash (equivalent of car headlights) hitting it....



Anyway, the next step is to wait for my 48 volt lith pack, order a controller, half throttle, x lyte 5303. I think while I wait I am going to begin the center mount case for the batteries, controller and tool/tube pack. I have been woking on the design in my mind, but still have to come up with anything more solid than the ammo box and modfied rack set up as on the blue bomber. Everything that I have come up with that is lighter is going to require thermo plastics, or fiberlass work. Does anyone out ther have any high tech acces to forming plastic cases?

Cheers,

len