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Re: Another EV bike :)

Posted: Thu May 29, 2014 2:46 pm
by flaninacupboard
Looking good, seems you may be riding by the end of summer!

Re: Another EV bike :)

Posted: Sat Jun 07, 2014 12:43 pm
by ChrisBarron
Hopefully :)

I've just run the bike up on battery power FIRST TIME BATTERY POWER !!! woohoo !

I need to replace a couple of suspension parts, but I've just found good quality parts on ebay very cheaply :)

So here is the video ! ...

I step the volts up 12 - 24 - 36 on old lead acid batteries to check everything is tight.

Then I connect 1 of the lithium packs...the bike tries to kick itself over with the torque and spins the rear wheel to 1150rpm. If that were on the road the speed (for the 600mm diameter wheel) would be 77mph. I'm too scared to connect 4 lithium packs in parallel just now. I need to make a decent stand and have it the right way up before I try that !

The chain is 112 links long, probably 2 links too many but I can live with it for now :)

Re: Another EV bike :)

Posted: Sat Jun 07, 2014 4:38 pm
by ChrisBarron
I've rebuilt the motor mount to perfect chain alignment, and when it started to rain I headed into the garage to build a proper rear wheel paddock stand.

Next job will be to fit the 4 lithium packs and secure them down before wiring in the controller and seeing how well it goes !

chain align.JPG
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Re: Another EV bike :)

Posted: Sun Jun 08, 2014 11:41 am
by ChrisBarron
The paddock stand seems strong enough, so here's a video of the wheel spinning up on the 4 X lithium packs (Yet to be buddied with a further 20Ah of Headway LiFePO4 cells ...

Re: Another EV bike :)

Posted: Wed Jun 11, 2014 11:10 am
by ChrisBarron
I ordered the endplates used for connecting the Headway cells together, but the plastioc spacers designed for use with Headway cells were out of stock. I was going to shop around but then realised I could make something myself, at least temporarily.

40mm waste pipe, cut to 15mm lengths and cemented to the ABS sheet seems to work fine.
headway1.JPG (95.24 KiB) Viewed 20800 times

On their way are the endplates for the Headway cells, some new suspension linkages and some front brake calipers (required for testing !)

I should probably look at wiring in the controller soon, but I don't have a throttle pot yet. I should probably get that first !

Re: Another EV bike :)

Posted: Mon Jun 23, 2014 3:10 pm
by ChrisBarron
I had the good fortune of being able to get the front brakes working thanks to an ebay find on calipers.... (rear brakes coming soon ! )

I fitted the batteries and motor, and located the controller roughly in it's intended location to get a couple of short tests in the garden.

I have to say that it performs as good as I might have expected it to, with the motor current limit would all the way up to about 200A, and the acceleration ramp rate set to maximum it takes off quite well. on the grass it's a handful.

In this video the controller is set to maximum speed so I have to pulse the 'forward' button on-off, but when taking off from the concrete patio the tyre gets enough grip to let the motor push hard !

First short test ride video is here > ...

Re: Another EV bike :)

Posted: Sat Jun 28, 2014 2:06 pm
by flaninacupboard
Looking really good, though your lawn won't thank you!! :D

Re: Another EV bike :)

Posted: Tue Jul 01, 2014 7:08 am
by ChrisBarron
I know, I don't have a throttle pot yet, so I set the speed using the controllers current and accelration limit pots and stabbed the power on off using a thumb button.

I've done a deal with forum member Skooler, who is sending me a curtis style potbox which I will be incorporating as soon as it arrive and then I'll think about transporting the bike to a private site I visit through work to see what it can do.

I've fitted a rear brake now too. When I spin the rear wheel up to full speed and let go of the throttle and stabe the brake the rear wheel stops very quickly and stays locked.......until I press the throttle and the torque which develops then overcomes the braking force. The brake pads are yet to bed in properly and there was probably a little bit of brake fluid on them too, but I'm surprised and pleased to see so much torque being developed. There's a chance I might get my 15 stone frame up to 50mph yet !

Re: Another EV bike :)

Posted: Tue Jul 01, 2014 9:44 pm
by ChrisBarron
Throttle pot arrived this AM and I managed to hook it up this evening....and find a quiet piece of tarmac to test on.

Initial feelings are that it might not get to 50mph, but it's too hard to tell of the acceleration is limited due to the motor current limit or an all round lack of power. I think a change of gearing could be required (larger sprocket to the rear).

However, it does go quick enough for me. Some onlookers commented that it looked quick and was incredibly quiet.

I checked the battery voltage. Pack volts were 41.6V last week, since then I've done a lot of wheel spinning in the back garden and stall testing, as well as pushing the controller hard making it drive against the back brake. And tonight I've a had a few minutes of full speed acceleration over 50 metres. Pack voltage is now 39.8V. At maximum acceleration the voltage sag was about 4.5V.

The controller has a bypass output, which shorts across the switch terminal to connect the battery pack directly to the motor, so I need to look into using that eventually.

Anyway, I feel happy that in it's current form it can keep up with local traffic with ease. I'm having some galvanised steel panels cut to size in order to clad the outside of the battery box.

Next job , I think, should be to integrate the Headway pack. Then I need to look at laying out a wiring harness.

However, it feels like I've passed a milestone now that I've been able to give it some running up to a good speed.

Re: Another EV bike :)

Posted: Sat Jul 05, 2014 1:27 pm
by ChrisBarron
Having realised that the gearing is not helping the motor work with it's current drive system, I decided I could either change rear sprockets (could be expensive to get one made), or try doubling the pack voltage.

I had read somewhere in the past that the EV10 24-48V controller I have can actually switch 72V packs, as long as a limiting resistor is introduced between the 72v supply and the controller logic board. I calculated a suitable resistance, reconfigured the pack for 84V max voltage and turned the throttle.

I can do a tyre smoking burnout now !

Riding the bike the acceleration is exceptional, like a good 400cc or 600cc bike. To save the pack I've wound back the current limit to where it is enough to get the bike rolling at a reasonable rate.

I'll have to reconfigure the headway pack from 12s2p to 48s, and then that means I'll also have to look at some battery management for that, but on the upside I have a pile of contactors, fuses and other electrical ancilliaries from a Lansing 72V forklift which I can now use, so I've saved a bit there. :)

The bike has a soft rear tyre and the chain is the largest 530 sized chain. Together these two things are adding up to a fair loss of power. perhaps I'll look at changing to a 520 size, or even smaller, chain and sprockets, in the future.