When it comes to bringing an idea to life it’s best to have both a sense of purpose, and an eagerness to apply whatever is on hand in order to get results. YouTube’s favorite Ukrainians [KREOSAN] are chock full of both in their journey to create this incredible DIY e-bike using an angle grinder with a friction interface to the rear wheel, and a horrifying battery pack made of cells salvaged from what the subtitles describe as “defective smartphone charging cases”.
What’s great to see is the methodical approach taken to creating the bike. [KREOSAN] began with an experiment consisting of putting a shaft on the angle grinder and seeing whether a friction interface between that shaft and the tire could be used to move the rear wheel effectively. After tweaking the size of the shaft, a metal clamp was fashioned to attach the grinder to the bike. The first test run simply involved a long extension cord. From there, they go on to solve small problems encountered along the way and end up with a simple clutch system and speed control.
The end result appears to work very well, but the best part is the pure joy (and sometimes concern) evident in the face of the test driver as he reaches high speeds on a homemade bike with a camera taped to his chest. Video is embedded below.
Personal electric vehicles are fertile ground for hobbyist experimentation, and while everyone might have their own take on a DIY e-bike let’s not forget that unique projects like the Snow Bike are out there as well.
Thanks for the tip, [bat]!
Not as scary as the Russians. At least the bungees will melt and auto release the melting burning cells.
I spy a Kelly controller!
Yep, looks like it, not something you just pull out of a trashcan. Could also be a Curtiss controller from a forklift with the paint removed?
No, it’s an inverter. six paralleled Li-ion packs in series for 24V into the large kW inverter. What they should have done was to rewind the motor for lower voltage or use an old PM dynamo from a car as a motor, that would have been far more efficient.
Too bad they didn’t have a battery operated grinder to use…
they should have wired the cells in series for 240v or whatever since the grinder will run on dc.
I’m pretty sure an AC grinder wants AC power though.
Pretty sure that the motors used in angle grinders are either series or shunt wound or PM, any of which will run just fine on DC.
That’s awesome. Slap together what ever you’ve got and make it work. Much more creative than buying some shiny parts from china
I agree…a proper hack
++!
That is a bike load of hacks, they seem to get a lot of joy out of the process too, great stuff.
How long until the armchair safety nazis come out of the woodwork on this one?
… not even a reflective vest!! :-o
This may very well have cause a total safety overload. I can’t name a part that’s not sketchy. I love it!
What’s wrong with suggesting how things could be done safer? I myself was horribly injured in a shop accident that could have been avoided if I someone with more experience had advised me to change my clothing. I’m all for wild projects and having a blast on homemade vehicles, but I’ll chime in if I see something unnecessarily unsafe.
It’s just normal toxic masculinity. Doing things carefully and safely is weak and not macho. Danger is manly, the more obviously and unnecessarily dangerous the better.
@markRD / armchair safety nazi, don’t forget the AWESOMEness factor of pulling off a great hack without injuring yourself or others while negating armchair safety nerds advice.
That’s called dumb-luck.
In high school I took an auto shop class taught by an old guy who was half deaf. One day he didn’t have enough tall jacks to raise a car up so he used a shop stool instead. I tried to tell him it wasn’t safe, but he couldn’t hear me. A girl’s foot got crushed when it fell and I’ve always blamed myself for not speaking up more.
About the only things I’d ding him on, is wearing sandals/thongs on an open-frame vehicle, especially an electrically assisted one, and I suspect his helmet was perhaps a size too big (seemed to wobble on his head a bit) but kudos for going for something better designed for a motorcycle instead of a bicycle helmet.
Ohh… and lighting up an aerosol can mounted to the back next to lithium batteries … a good way to wind up with projectiles up your bum!
I wouldn’t be comfortable with 220V AC being live on the bike myself… but that’s just risk-averse me. If they could figure out a motor that runs on 24V or 48V, that might be safer, although the trade-off here is that the conductors have to be bigger to take the current, and there is where the extra weight of standard electric bicycle motors comes in.
This set up wouldn’t be legal on Queensland roads, given the power of the motor (I think the limit is something like 200W or so… and it has to operate only when the cyclist is pedaling)… but off-road, you’d be fine, legally speaking, not that I’d want to take that bike off-road anywhere with 220V and a live angle grinder.
Perhaps it is possible to reconnect the series wound AC motor to parallel connection (field and commutator in parallel) and run it directly on 24V DC? But it’s possible that you need a small step down converter to reduce the field voltage (and current).
Here in the UK it is 200W/250W and has to be type approved if it has throttle assist, IMHO is much needed on hub motors, Bottom bracked motors however have a better assist ratio and thus unlikely to cause injury without a throttle to limit power.
Oh and 250W is due to compatability with many parcipitating European countries’ people visiting/working here in the UK…. It might change/become strict.
Oh, unofficially, you’re allowed higher wattage but has to be restricted (and possibly type approved)
see here for our (UK) Governments’ vague details[link]
So rusty is the implementation of said laws that the rider would have to check the corresponding legislation (and it’s applicability/enforceability) and even then the laws are arguable to a degree…
Sometimes it is up to the officer, judge, whom-ever and what mood they’re in that day…
It helps to show you’re sensible with your equiptment and be polite where possible… It can make a difference.
Interesting experience:
A few friends and I was riding about on a couple 75cc engines strapped to pushbikes and used them over in the mountainous roads of Wales.
We only used them at day and had lights, bells and helmets.
One time at an intersection a Riot van patrolling the area (as a shift, The Welsh are rough I guess) was waiting for traffic clearence before exiting. We pull up along side…
Officer sticks head out of the window.. We greet politely… explained about the one-off event and the bikes mostly being used on private land…. Officer asked us to stay safe and left.
Most times, officers local to the area just seemed to not mind.
Likely because we showed we’re being sensible, polite and due to loads of private fields around the area.
.
.
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TL;DR:
E-Bike laws are vague (a grey area), Be sensible and show that you’re sensible, if pulled over then be polite and explain the situation, it may improve your chances of being left alone and keeping the bike.
I doubt e-bike laws are vague at all.
Drone law sure, but E-bike laws are well established now methinks.
This is post-apocalyptic style, use parts you can find laying around. So safety is not very relevant.
Rinoa has done something similar but with a lot of 18650 cells Tesla style.
As an aside, did I hear a couple bars of “Tovarisch Gorbachev” by “Midnight Moscow” around 5:50 into the video?
“This piece is interfering with the motor. Give me that angle grinder …. crap.”
If it works and he is content with riding it why are others knocking him? I give him a” hell yeah” FTW. Keep on doing what you’re doing and don’t worry about what others think or say. Good luck and keep on doing what makes you happy
Anyone else getting (classic) Mad Max vibes from the helmet, the glasses and the overall look of this hacked-together e-bike?
In other news, [KREOSAN] are still alive :P
are they? the young dude from earlier videos is missing :)