The new old new ebike!

General Discussion about electric bicycles.
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jonescg   10 GW

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The new old new ebike!

Post by jonescg » Aug 17 2013 3:59am

As seen in the Battery forum, I bought a box from Kiwi and mounted it into my old steel framed Trek. I finally finished wiring it up. What I really long for is a simple, solder-bucket type circular 6 pin connector with some level of waterproofing. Cause I gave up and used JSTs from HobbyKing, which work but look bloody terrible.
Ebike done 2.jpg
Ebike done 2.jpg (291.71 KiB) Viewed 3378 times
I put everything together and turned it on. All good. Went to pick the bike up and twist the throttle, but the wheel started spinning! Turned it off, walked outside with it and tried again. Nothing, slight delay, ZOOM! The bike shot off, did a huge wheelie and fell over! I flicked it off, figuring I had a throttle problem. Sure enough my lack of decent connectors lead to the shorting of the wiper to the 5V. Full throttle, all the time. Whoops :) So I tidied it up, taped it up and we're golden :lol:
Ebike done 1.jpg
Ebike done 1.jpg (184.76 KiB) Viewed 3378 times
I finally got around to putting the spacer between the hub and the frame so I can use the smallest sprocket. I only ever use this gear on the top chainring so I should be good for 60 km/h with a brisk pedal rate. I also have ~750 Wh onboard with the LiPo pack, so I should have about 30 km range under 'typical' use :twisted: .

The button is a 500 ohm precharge circuit which you hold down while you flick the switch down - perfect one handed operation. The switch is a DPDT toggle with a waterproof cover. These are rated for 10 A on 240 V AC, so I just soldered the 8 gauge wire across both poles so it's effectively 20 A continuous. Just as well, cause a giant isolation switch would look like a dog's cobbler.

All that's left to do is make an 8 wire harness from a DB15 to go to a couple of Cell-log-8 modules which can be velcroed to the top of the box. I have no cycle analyst, no voltmeter and no speedometer. So the cell log is all I'll have.

Now that this is out of the way, I can fit the new race bike in the shed :twisted: :twisted:

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amberwolf   100 GW

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Re: The new old new ebike!

Post by amberwolf » Aug 17 2013 3:19pm

jonescg wrote: What I really long for is a simple, solder-bucket type circular 6 pin connector with some level of waterproofing.
Look around at junkyards for old aircraft wiring harnesses and equipment. They often use Canon (cannon?) connectors, which while they often use crimped pins rather than soldered, can easily enough have the existing crimped wires cut off just close enough to do a lap solder joint to them, and heatshrink that. ;)

And those are almost always decently waterproofed, easily helped with a little dielectric grease at the contacts, and whatever you like on the back end.
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boostjuice   10 kW

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Re: The new old new ebike!

Post by boostjuice » Aug 17 2013 8:54pm

Amberwolf, Australia doesnt have 1000's of acres of mothballed and part-salvaged aircraft graveyards like the US. I'm sure Chris would be able to find something ideal with enough searching through auctions of high-end old-school communications electronics though. But in the end a decent quality set of nickel plated DB-9/15/24 connectors with gold terminals is hard to beat for ease of availability and corrosion resistance (doesn't need waterproofing to maintain reliable interconnects).

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