Homemade E-Bike 2000 watt

Hello everyone

I'm new here and I decided to show some pics of my e bike project I've been up to, since last summer. I have build an e-bike before but I decided to get some more power this time. This bike was an old city bike and had a 48v 700w e-bike kit on it from Ebay.
I wanted to build a faster bike but also a more reliable bike, this time, that can handle some though off road biking.

After searching and comparing some e-bike kits (which were higher powered than 1500w) I decided to get a 2000w 48v kit from uumotor.com. Ofcourse I needed a good battery, too. I've got a 30AH one from Vpower.hk. After some searching and asking around in the neighbourhood I got myself a crappy old mountain bike. The frame was OK and it still shifted gears well enough. It had no rear suspension and a really cheap from suspension. But I'm happy with it because I wanted to build suspension by myself.

I think you want to get some pics of it now, don't you?

This is the bike all finished up:




This was the previous version of the bike. I attached a strong bag at the seatpost to fit in the 15AH battery (this one was from my electric scooter).


At first, I started demounting the whole bike. To fit in the brand new 30AH battery I had to cut some corners out of the frame. After that I welded angle bars in.



Then I started with the new swingarm. I cutted away the old swingarm but I left the upper frame tubes with the "wheel holders" on their original position so I would get a perfectly aligned swingarm. I welded angled square bars between the pivot point and the wheel holders. Then I removed the upper frame tubes.


I've welded a frame right next to the battery (yes the other side is removable ).


I added extra tubes on the swingarm so I could attach suspension springs between the swingarm ant the frame.


A fast bike needs good brakes. That's why I decided to add dirtbike hydraulic braking systems to it. I made a connecting piece to attach the brake disk to the wheel hub.


I needed to mill out some material from the disks to fit in the bolts. This was a nasty job to do... I don't own a miller so I attached a pneumatic hand miller to our drilling machine with a movable table and cutted out the material carefully.


To attach the front brake to the front fork I made a connecting piece.



A professional painter sand blasted the frame parts and sprayed the primer on it.


The top coat I did by myself at home. I didn't want everything the same color so I made the angle bars black.



Assembling... (The new front fork is a SR Suntour XCM V3)


The bike drives very good.. I love the new suspension on it.. The braking is much better than it was before. The whole bike is a lot more stable to drive. Top speed is about 30 mph and range is about 30 miles.

I hope you guys like it and I'd love to hear some comments from you :wink:

Nicely done! Big applause from me! I love the way you addressed the need for dual rear shocks by placing them low. A nice choice to utilize the low space.

A couple of questions....

How is the lateral stability of the rear forks. In other words are you getting any lateral flexing at where the swing arm attaches to the frame? How do you remove the batteries?



PS

Not sure about shock mounts. Does not look enough support..

It's definitely interesting, though I see a few mechanical compromises that I wonder how long they would last under rough conditions, including the shock mounts on the downtube (especially since the downtube has the cutout and angle welded in there).

You might consider gussets in front of those mounts, extending thru the bottom surface of the downtube to the inside face of the downtube's top surface, and welded in both places.


That said, my CrazyBike2 is full of compromises and though it has required a number of serious modifications over the years to fix problems, it *has* lasted years so far.

amberwolf said:

It's definitely interesting, though I see a few mechanical compromises that I wonder how long they would last under rough conditions, including the shock mounts on the downtube (especially since the downtube has the cutout and angle welded in there).

You might consider gussets in front of those mounts, extending thru the bottom surface of the downtube to the inside face of the downtube's top surface, and welded in both places.


That said, my CrazyBike2 is full of compromises and though it has required a number of serious modifications over the years to fix problems, it *has* lasted years so far.

Click to expand...

Those tubes are welded all around, it will almost never break off

e-beach said:

Nicely done! Big applause from me! I love the way you addressed the need for dual rear shocks by placing them low. A nice choice to utilize the low space.

A couple of questions....

How is the lateral stability of the rear forks. In other words are you getting any lateral flexing at where the swing arm attaches to the frame? How do you remove the batteries?



PS

Click to expand...

Thank you very much

The left side of the subframe is removable. It's attached to the frame with fasteners.
The springs are actually very rigid. While driving on this bike you will notice that the front suspension does more than the rear suspension because it's so rigid but I'm happy they're there because without them, driving on bumpy roads is very uncomfortable.

Interesting bike & nice photos of the adapted brakes.

How well do the brakes perform?

+1 like it. Ditto technical feedback from the experts. For future fans of the process - start your build thread day one and get that feedback before you invest money/time/labor. What I like:

• it was DIY and took some technical skills & tools to pull it off
• got your frame cheap/used and made an analysis of what it'd take to improve for speed/power and ride
• did improvements to add in disc brakes and full suspension
• enlisted the help of your local community for things like the paint job
• shopped around for motor & battery to get the power you wanted
• completed your project and posted pictures for the ES community

FYI, I've added in your pic to the Imaginarium, a slideshow I've put together for makerspace eBike workshop I run, wanting enthusiasts to first exercise their imagination of the possible, to dream a little.

teakuh said:

Those tubes are welded all around, it will almost never break off
http://i.imgur.com/R9wnpOy.jpg

Click to expand...

I do hope they don't, but I have seen similar structures under similar expected forces in my own creations fail because the tubes they were welded to the surfaces of (instead of thru and onto the other surface, and without any gussets) buckled under repeated shock loading. It could be my materials were just weaker; everything I make is from assorted junk someone else didn't want, and I rarely know exactly what materials it's made from, other thatn "steel" or "aluminum" or whatever.


So I just wanted to give you a heads up about the potential problem, so you can keep an eye on the tubing in that area. If you notice any deformation in the surface of the dowtube, you may want to consider at least gussets.

voicecoils said:

Interesting bike & nice photos of the adapted brakes.

How well do the brakes perform?

Click to expand...

Brakes are good, they never block the wheels completely (which is a good sign) and the bike stops really fast and safe. The brakes are designed to stop a lot heavier and faster bikes than this one because I bought them from a dirtbike parts shop.

amberwolf said:

teakuh said:

Those tubes are welded all around, it will almost never break off
http://i.imgur.com/R9wnpOy.jpg

Click to expand...

I do hope they don't, but I have seen similar structures under similar expected forces in my own creations fail because the tubes they were welded to the surfaces of (instead of thru and onto the other surface, and without any gussets) buckled under repeated shock loading. It could be my materials were just weaker; everything I make is from assorted junk someone else didn't want, and I rarely know exactly what materials it's made from, other thatn "steel" or "aluminum" or whatever.


So I just wanted to give you a heads up about the potential problem, so you can keep an eye on the tubing in that area. If you notice any deformation in the surface of the dowtube, you may want to consider at least gussets.

Click to expand...

Thanks for your advice I will pay attention to it.

I love this bike very creative.

Mooi fietsie

heey wat leuk
ik heb zelf ook een e bike gebouwd.
hier dit is de link naar mijn fiets: http://endless-sphere.com/forums/viewtopic.php?f=6&t=59104
hij is nu af alleen moet ben ik nu alles aan het fine tunnen.
ik zal vandaag de pagina updaten.

gr louis

haha foutje dit is mijn account en niet die van mijn broer :wink:

Zeer mooie fiets. Je hebt een aantal vaardigheden. Oranje is ook een van mijn favoriete kleuren, zodat u extra krediet te krijgen voor dat. Good Luck met. Ik hoop dat het dient u goed.



I'm just jumping on the Band Wagon. Google translate is my friend :lol:

'Cal

Ch00paKabrA said:

Zeer mooie fiets. Je hebt een aantal vaardigheden. Oranje is ook een van mijn favoriete kleuren, zodat u extra krediet te krijgen voor dat. Good Luck met. Ik hoop dat het dient u goed.



I'm just jumping on the Band Wagon. Google translate is my friend :lol:

'Cal

Click to expand...

Thank you, orange is a nice outstanding color

louis raaijmakers said:

haha foutje dit is mijn account en niet die van mijn broer :wink:

Click to expand...

Thank you! your bike is nice, too. My first idea was making a replica of the "Stealth" bike just like you did. But I only have construction steel at home and no aluminium so the plates on it would be way too heavy. I also don't want to stand out for the local police because these bikes are actually illegal to drive in the Netherlands (my bike gets an top speed of 30 mph without power assist while the max. permissable speed here is 16 mph WITH power assist).
I decided to make an "Aprilia motorcycle look a like" frame and make the bike compact as possible and the battery almost invisible, but still an attractive bike to look at.

Great diy ebike,i would look into getting a full flat floor under the battery bottom,it will get beaten down in the middle over time with 2 end pieces holding it.

How was uumotor to deal with? They had a E Scooter hub motor I'm thinking about trying. Anyone else use them?

tomjasz said:

How was uumotor to deal with? They had a E Scooter hub motor I'm thinking about trying. Anyone else use them?

Click to expand...

uumotor has a good service, they answer quick and are very helpful. The shipping took a view months to the Netherlands.

I'm just curious how everything has held up, and how well the brakes have worked out for you?

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