The Hayashi Project (mid-drive, hand-made frame)

[rafzan]

Hello ES members!

I'm a newcomer to the electric bike subject. Been studying physics and electric vehicles for a while and now i thought it was time to go further.
A friend told me about this guy, Andre Hayashi, who was selling his e-bike project. He was a product design student at the time, and this was his graduation project. He sold it to me cheaply cause he was goin' to another country. Lucky me.

Its a carbon-steel frame with 1000w motor and controller. Unfortunately, no reduction gearing

Thats how i got it, with this heavy and stupid fork, and without this shitty batteries too. Took out the heavy front wheel too.

Ill be making another posts with the rest of the pictures, so this article stays organized.


Im using these cheap (not so) batteries cause of the budget. Im just a teacher, and this bike is not my priority. They will give me only 2.5 Amps, at 60V, lousy 150W. Its ok to the prototype phase, but when its done ill be buying these:

plus infineon controller from ebikes.ca and a 80100 from store.electricbike.com

 

[rafzan]

For future references, This is a brushed GOLDEN MOTOR "1000W', with a YI-YUN controller.
This controller had burned all three FETs, they were "K4145".
Following advice on this board, i substituted them for "IRFZ48N", first ones who could handle 30V and 60A i could find.

At the same stage i have bought a Sr Suntour EPICON fork and Avid Juice Three disk brakes for the bike. Im using a 220mm rotor that came with it.
Can anybody tell me if this is ok? Is it better to use small rotors? The bike + me will have final weight of +-110kg...

Later on i bought an Arduino, and instead of buying the Cycle Analyst, ill try to make my own computer.

yeah, im brazilian

 

[rafzan]

I cutted the frame where the crank arms were touching it. Ill have to buy new crank arms as these ones are HORRID. Look at the second pic.

Don't mind the soda bottle chain guides... that's why i bought the PVC on the third pic...

Also bought a lot of materials and some swag to work on the bike.

 

[rafzan]

Here i'm working on a aluminum chainring adapter and drinking some stella.
This shit won't end up beautiful, but functional its ok to me.

Smooth edges where the bolts will be touching, to give it firmness

Here is the finished freewheel chainring:

I would use the white industries freewheel, but this dicta was bought locally for 1/10 of the price. Easier to repair if something breaks.
In fact, this bike had a chinese one who just falled to pieces on a test. Shittiest piece of bike i have ever touched.

 

[rafzan]

6:1....

And 4:1.

Then I have 10:1 suggested reduction. I hope i'm right. Please correct me if not so. These pulleys were really expensive.
Now i gotta work the motor shaft and the smaller pulley so they can interact.

 

[rafzan]

Also, when i opened up the motor, i remembered this strange thing:

https://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-ash3/943207_10201247266089584_936599931_n.jpg

There is one brush that's strangely disconnected.
When i put it to work, the motor make a strange noise.
If you look on the wire that connects it, its a little rusty. Ill try making the connection good again and see if the noise disappears.

Can someone tell me what this means? Is it wrong to get the brush down?

 

[kfong]

All 4 brushes should be near center. The one that is off, needs the spring repaired.

 

[rafzan]

All 4 brushes should be near center. The one that is off, needs the spring repaired.

Hello, thanks for the reply. Good to know the 4 brushes should touch the center.

The spring is ok, and the brush is just "locked" up there. When its down, the motor makes a strange noise. Ill try making a video.
The thing that's damaged its the soldering from the wire - its kinda oxidated (you can see it just behind the spring). Ill try sanding and re-soldering the place to see if the noise goes away.

 

[spinningmagnets]

if your freewheel ever wears out, this guy (Mel, at bikemotive)has been starting to sell popular E-bike products to make him a one-stop shop. His ACS-Crossfire based FW is $19:
http://www.ebay.com/itm/ACS-Crossfi...Cycling_Parts_Accessories&hash=item4abe8ce28f

 

[rafzan]

Ill surely check his store!!

I have already seen these freewheels, but didn't notice the other products. Since i'm brazilian and importation here can cost up to 110% of the original value, i prefer to buy things locally, but can't do it with some really specific things.

as an example, I was looking for a bigger sprocket, and have found this magnificent store on 29'er forums:
http://www.ebay.com/sch/mtbtools/m.html

FREAKING 41 teeth. Heaven for heavy bikes like mine. I'll try to make it the more versatile possible, with a front derailleur for 2 chainring (22T and probably 28T) and 10-speed range on the rear, with this 41T sprocket + a 9 range sprocket up to 11T. Thats it for 10 speed. Well, the guys on this 29'er forum said that could work. Let's see...