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Custom middrive hardtail (with GNG motor)

Posted: Dec 11, 2017 8:27 am
by vlaca2
Hi All!

This is my first middrive build log.
I built one rear hub driven Specialized Bighit, its working fine, but i want some different beast :)

I selected GNG electric motor and LightningRod’s one stage idea.

67kV motor, 12S Lipo cca. 3200rpm full throttle.
12T/85T 219H chain, 1:7 reduction to BB (cca 460rpm on BB, less stress on components, no pedaling :) )
24T/48T bikechain 1:2 reduction to rear wheel.(cca 260rpm, low speed, high torque :)

The 48T and 42T is front chainwheel, mounted to cassette with special adapter. The other rear sprockets is from 8S cassette.

Now in test period i use 42T/48T and enjoy the torque :) The shifting partialy working, need some fixing for speed setup.

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Components:

- Magellan PolarX hungarian dirt/street frame.

- GNG motor, 67 kV “small block” from GNG
- GNG 12T 219H sprocket from GNG
- 85T 219H carting sprocket from local carting shop
- 219H 106 links carting chain from local carting shop
- 24T front chainwheel, 5 holes direct freewheel mount from Cyclone
- ACS freewheel from Eclipse UK
- 148mm ISIS BB from Cyclone
- ISIS freewheel mount crankset from Eclipse UK

- 3/32” bike chain from local bike store

- cassette to104BCD front chainwheel adapter from ebay
- 48T and 42T front chainwheel from local bike store


- Greentime 1500W / 40A controller from Greentime
- Turnigy Graphene 8000mAh 6s 15C 2pcs from hobbyking


First offroad test video:




https://www.youtube.com/watch?v=L4o_SCjO4ww

Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 11, 2017 8:30 am
by vlaca2
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Test fit



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Bench test.



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Motor mount plan.



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Chainwheel adapter plan



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Chainwheel assembled

Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 11, 2017 8:37 am
by vlaca2
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Motor mount.


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Motor mount assembly



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Motor mount assembly

Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 11, 2017 8:39 am
by vlaca2
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Front chainwheels in cassette adapter.

Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 11, 2017 8:42 am
by vlaca2
Throttle test:


Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 18, 2017 5:05 am
by vlaca2
Update1:

New handmade derailleur hanger for 48T/42T:
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Installed ok:
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Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 28, 2017 7:48 am
by vlaca2
Short training video :)


Re: Custom middrive hardtail (with GNG motor)

Posted: Dec 29, 2017 1:21 pm
by Emoto
nice build , like the alloy motor mount, i like alloy :) , nice music too keep it up man.

Re: Custom middrive hardtail (with GNG motor)

Posted: Jan 02, 2018 9:46 am
by vlaca2
Emoto wrote:
Dec 29, 2017 1:21 pm
nice build , like the alloy motor mount, i like alloy :) , nice music too keep it up man.
Thanks! :)


Circle (of power) :) :) :)


Re: Custom middrive hardtail (with GNG motor)

Posted: Jan 22, 2018 2:19 am
by vlaca2
Hardtail ok, but i need full suspension.

New build coming... :) :) :)

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