Road Racer Ebike

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safe
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Road Racer Ebike

 

Ebike - Side Scenic.jpg

 

http://sfbay.craigslist.org/eby/bik/5839792278.html

 

You can see the project here:

 

http://www.twospoke.com/forum/f27/safes-project-003-a-10614/

 

With a Kelly Controller set at 50 amps I have pulled 50 mph as a top speed, but I've geared it lower so the top speed is now 30 mph. (changing the gearing is easy, just get a smaller rear sprocket for $10)

The throttle needs replacement... the hall sensor went out. Plus you have two controllers to pick from.

Currently the bike sits in pieces in my mother's garage and she is in declining health (in a wheelchair) and making a rather sudden move to a nursing facility. I live in Wisconsin these days.

So the price is a fraction of the effort put into it. (literally years)

If you want a fun project at a good price this could be for you.

Email through Craigslist

 

safe
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Re: Road Racer Ebike

 

Step Up to 80V at 40A.gif

 

An Update...

Mother has moved into Assisted Living. Condo is not going to be sold yet as I'll move out there and live in it for a few years until my mother passes away. This means I'll actually get a chance to use the ebike again and one idea I've toyed with for a long time is to Step Up the voltage to 80 volts using a pair of 20 amp voltage regulators.

Since it's a brushed motor this is easy to do in one step. (not so with brushless)

The advantage is that the gearing can remain low (meaning more torque for the same level of heat) but the top end will come back like I had the bike setup when it was geared taller.

240 Watts of heat won't even cause the motor to heat up. (from past experience)

Downhill it should reach a theoretical maximum of 65 mph.

After I get it perfected then I'll sell it.

 

safe
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Re: Road Racer Ebike

Have moved back to care for my mother now.

The ebike has been perfected and I have ridden it at least 5,000 miles.

Works great and a lot of fun.

And I have a fully functioning garage now as long as my mother continues to live... at 85 years old... and unable to walk.

So if anyone wanted to know "Safe" is alive and well.

------------

Technical:

I'm running a brushless sensorless skateboard motor now at a 10:1 gear reduction through the 219 chain. (10, 100)

Upgraded to Maxxis Hookworm (24") tires and the grip is astonishing.

Two cells in the battery died, so I replaced them with A123 20ah pouch cells and that repair was not too difficult.

New hubs front and rear just to upgrade the quality.

Will be installing new sealed bearing bottom bracket soon as the old style ball and cup now has wear and problems.

safe
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Re: Road Racer Ebike

VESC is AWESOME

No longer in California and now in a place with a big garage to work in again.

This bike continues to be improved and has something like 25,000 miles on it because I ride it all the time and have been doing it for years.

All I want to talk about now is the big, big improvements in the ESC hardware and the brilliant work of the "V" is for "Vedder" in VESC.

Compared to the Chinese Brushless Controllers you get for $30 the newer VESC is about five times more "intelligent" in that the ERPM is now as high as 150,000. The old Chinese crap could get to 28,000 in Sensorless Mode but then went into dumping random current pulses because it could not keep up.

With the 6.0 level VESC like the Flipsky 6.9 I'm able to get near perfect brushless, sensorless performance from just a few start up rpms.

And the ability to customize EVERYTHING is both wonderful and scary... you can seriously screw up so spend some time getting it right.

I also upgraded to a 1.33 kWh battery so my range is about 40 to 50 miles and the VESC even records the data. It's running roughly 30 wh per mile when I'm pushing it hard.

And the tires are getting full wear on the edges too. It's funny that I'm actually wearing the edges off first and the front still has good rubber on the top.

Anyway... I'm still doing this stuff all the time.

My next upgrade is a "Copper Modding" of the MOSFETS which should dramatically improve the cooling of the VESC. As it is now on some of the longer hill climbs I will get some temperature related current reductions. I bought copper plates to replace the rubber pads. With computer heatsinks they do this upgrade and it seems to work well.

safe
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Re: Road Racer Ebike

Mileage.jpg

This was data from the ride this morning.

The VESC cools quickly once you stop... but it can be better.

safe
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Re: Road Racer Ebike

Battery Performance.jpg

Most of the battery was used.

Regen is set very low... only 5 amps.

safe
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Re: Road Racer Ebike

RPM Configuration.jpg

I'm doing something weird so let me explain... the motor gets into serious vibration above 4000 rpm so I'm limiting it to 30,000 ERPM to keep it stable.

But I'm also reducing a 100 amp Battery Current Limit early (40%) which softens the high rpm torque.

It works well and makes compromises I can live with for now.

safe
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Re: Road Racer Ebike

Quick Update.

The "Copper Modding" was a massive success and allowed me to push more watts through the system than before.

Unfortunately the motor was not up to this increase and burnt up on an aggressive sequence of hills.

So I'm doing a bunch of redesigns with Chinese Drone motors to try new things.

The bike is always being improved... still my favorite hobby.

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