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Carbon 29er hardtail 350w Bafang mid


100 W
Dec 11, 2013
16Ahr Panasonic downtube battery & 350w Bafang both from Pirez bikes here in Australia.

Frame is a Chiner bought 2015 March @ 364USD or 476AUD.
Forks Rockshox Reba
XT gruppo
Xpedo pedals
SunRingle rims/ hubs

Material removed from BB to get clearance for the Bafang; to be re-laid inside; UHM tows.

Battery bottle mount frame had 103g liberated by removing surplus metal; it's redundant.
It's only there for production efficiency since they use the same mount for hub motors and they
use a controller in that space that needs the extra metal as a heat sink.

Estimated AUW sub 20Kg


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With 500km under its skirt I can report it's a fantastic solution.

The big wheels with 2.2 Maxxis tyres are great for comfort (not so great for efficiency).

The BB void was filled thanks to a mix of resin (West Systems) and cut up carbon tows.
The slurry was re-introduced into the void under the BB and then taped-over (masking tape)
and left to cure.

Great result IMHO.

What battery are you using? I have a bafang 350w motor and a friend gave me a 48v ~12 amp battery but when I put them together I get an error code 7 (high voltage). I am trying to decide if I need to get a 48v controller or a 36v battery...
36v 16Ahr


...matched to the 36v 350w motor.

The controllers for Bafang mid-drives are inside the motor end housing.

This bike has done 751km and is brilliant; the best eBike I've assembled so far.
I swapped out the standard Bafang chainring for a 46t alloy with 104BCD adapter
and the drivetrain is pretty smooth.

Next up is swapping out the 10-sp XT DR, chain and gear lever for the Shimano 8-sp equivalents.
The 8-sp system is better suited to high torque.
Cool thanks. I am trying to decide to get a 36v battery (~$300) or a 48v contoller (~$100). Nice build, I hope to have mine up and running soon a well.
Update Jan 2020.

I can't break the drivetrain. I want to so I can replace it with a 9-spd system ;0)

New pedals, drivetrain regularly waxed (dry wax lube is the best), motor, batt., charger and controller are hassle-free.

Odometer is 984km.

Gearing is spot-on; 46T drives an 11t - 32T cassette. I only use 11,12,13 and 15 cogs .

Tyres are fine but draggy, so next set will be "touring" tyres but not Schwalbe 'cos they weight a tonne.

Looks great. Thanks for turning me on to Emax many years ago; my BBS02 system is in its fifth year (AIR) powering a MTB hardtail and doing it with aplomb.

Added later: today 12.6 miles, 2100' ascent on some fairly smooth, but (in a couple of areas) brutally steep ascents.
Hi 2Old.
Good to hear.

Two more colleagues here at work have converted their bikes too.

One of which is a Kona tourer with dyno for lights and leather saddlebags.
2330 km under its wheels. Mostly daily work commuting, 18km return trip.

Rear wheel developed crack in rim around 1900km.

Replaced with Shimano MT500

Great wheel IMHO.

Tyres are efficient but puncture prone; glass shards mostly. I get a puncture every 1-2 months.

Reba forks are great; stable and easily adjustable.

Drivetrain/ battery / charger: faultless.


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Update: 2023 April

This bike continues to perform beyond expectations.

It's just a commuter, but rain or shine, it doesn't stop delivering me to work and back. The charger charges, the bike delivers grins and my carbon footprint is better than a skinny Bedouin.

The Shimano Altus 8-spd DR, CS-HG51-8 bf 8-spd cassette, and 8-spd chain (also Shimano) are a good compromise between cost/performance.

TBH a 5-speed system would be better for me, the top 3 ratios aren't used.

Running costs have allowed me the occasional luxury.


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Great to hear. My BBS is in its eighth year (now piloted by my son) with neither maintenance nor problems. He rode it 100+ miles a week last summer. My first "cassette" was 11-17-28 cogs spaced 8-speed on the end of the freewheel. You might consider just orienting your three gears with spacers the next time you change.
It just goes and goes.

Nothing's broken, no strange noises, no chain-skipping, drivetrain cogs are still good, performance still optimal even over Winter her in Tas.

Tyres are looking a bit bald and disc pads need replacing every 6 months.

The battery charging cord plug/ socket (the small round one that goes into the pack), is a little wobbly but still charges ok.

If I had to upgrade anything I'd get the colour display just because it's colour.