-Bugsy-
100 mW
Over the past 12 months I've been lurking on the fringes, eyeing off everyone's creations here on E.S. Many ideas have crossed my mind. Some more radical than others, but thought that a nice (simple) hub motor build could be a good place to start to get a feel for this E-biking thing and working with LiPo.
Rather than build a dedicated donor bike for the power kit to go into, I decided to retrofit my DH race bike with the hub motor. It takes about 45 minutes to swap between DH mode and E-powered mode. So during the week I can go out and enjoy fast, flowy single-track without the exertion of peddling my ass off. Then on the weekends I can swap the wheel-set over and enjoy the bike for what it was built for.
Bike Specs:
Intense M6 - Raw hand-polished aluminium
Boxxer world Cup forks (2010)
Avid Elixr CR 8" hydro brake-set
Mavic Deemax rims
E-Power Specs
BMC V3 hub motor
BMC 50A controller
Crystalite Throttle
LiPo 16s 2p - 44v @ 11.6 Ah (currently) Couple of other random spares as well.
CA-DP
First up. A big thanks to Ilia at e-bikes SF for answering all my noob questions and supplying my kit. Thoroughly recommend dealing with him.
Batteries, charging system and misc bit n pieces - Hobbyking. Just can't argue with their prices.
BIke - Custom built by myself for this years race season. It's awesome! Many parts sourced from chainreactioncycles.com. All mail-order from UK but pricing is like having sponsorship.
First up came the job of lacing the motor to a rim. Ilia recommended a velosity cliffhanger rim and supplied the spokes to suit the ERD of this rim.
Ypedal has a great vid tutorial on the easiest way to lace a heavy hub motor to a rim. Tips n tricks helped me out a lot. thanks..
Managed to get the rim dished, trued and balanced and decided on a set of Maxxis Holy Roller tyres (2.5") Far less rolling resistance than the Minions I usually run offroad.
Mounting the motor in the frame I came across my first challenge. 150mm dropouts in the bike and 135mm spec on the motor. Lucky for me I had a spare set of 135mm dropouts that suit as I didn't like the idea of shimming out the 150's with washers.
I next discovered that there was a small gap in the dropout where the motor axle has been bevelled.
To fill this gap I noticed that another member had resorted to using split pins cut to size and filed down. So that's exactly what I did. Protects the expensive aluminium dropout from being thrashed out by any axle movement.
View attachment 4
Next up was mounting the brake rotor. I treated myself to something a little bling (nothing to do with the expectation of fire coming out of it). But found that it didn't even come close to lining up with the calliper. A bit of creative washer spacing was called upon. Both inside the disk and between the calliper mounting block. Now it's spot on.
Turning attention towards the batteries, I've noticed a lot of different opinions of Anderson vs Deans vs Bullet connectors but decided to standardise the entire configuration to 5.5mm Bullet connectors so that I can have a play around with different voltages and capacities etc. Soldering up suitable parallel link leads and charging connections etc. Seems to be working OK. Despite some inattentive, Rookie shorts that ended in molten metal on the wall (another story).
Mounting the battery pack. Well for now I went with a seat-post mounted Beam Rack. Seems to be a few of these kicking about. Only trouble was the rear of the bike has so much suspension travel that the rear tyre was rubbing on the rack over the smallest of bumps. Even with the preload wound full on.
Spinning it around forwards is proving to be a viable alternative. And the bike handles one million percent better without that weight hanging over the back wheel. It reminded me of taking a 100Kg Pillion passenger for a ride on the Moto. That's how much it affected the bikes edge to edge performance and turn in. May just stick with it for now 'till a better alternative presents itself. I also think it's kind of stealth with the bag hidden by your body and legs as you blast past onlookers just in time to see their WTF face.
Preliminary tests have given it a 40km range (with a bit of peddling involved to stay warm) and a max speed of 66Kph clocked at the local valendrome.
------------------
Additional notes. I have since gone on to add a pre-charge resistor to stop that awful arcing when connecting the battery pack. Also sick of resoldering new bullet connectors as they don't tend to last too long with that kind of arc. Ended up running with a 5watt 220 ohm resistor that is connected first to allow the caps to fill.
Still needs some fine tuning but pretty happy with result.. And it's been a very enjoyable project. Learnt a lot, and working on other ideas. More will be revealed. I like this E-bike thing! Got my eye on the Hanglider soon.........
Big thanks to all members posting their experiences. Wouldn't be able to do it otherwise.
Rather than build a dedicated donor bike for the power kit to go into, I decided to retrofit my DH race bike with the hub motor. It takes about 45 minutes to swap between DH mode and E-powered mode. So during the week I can go out and enjoy fast, flowy single-track without the exertion of peddling my ass off. Then on the weekends I can swap the wheel-set over and enjoy the bike for what it was built for.
Bike Specs:
Intense M6 - Raw hand-polished aluminium
Boxxer world Cup forks (2010)
Avid Elixr CR 8" hydro brake-set
Mavic Deemax rims
E-Power Specs
BMC V3 hub motor
BMC 50A controller
Crystalite Throttle
LiPo 16s 2p - 44v @ 11.6 Ah (currently) Couple of other random spares as well.
CA-DP
First up. A big thanks to Ilia at e-bikes SF for answering all my noob questions and supplying my kit. Thoroughly recommend dealing with him.
Batteries, charging system and misc bit n pieces - Hobbyking. Just can't argue with their prices.
BIke - Custom built by myself for this years race season. It's awesome! Many parts sourced from chainreactioncycles.com. All mail-order from UK but pricing is like having sponsorship.
First up came the job of lacing the motor to a rim. Ilia recommended a velosity cliffhanger rim and supplied the spokes to suit the ERD of this rim.
Ypedal has a great vid tutorial on the easiest way to lace a heavy hub motor to a rim. Tips n tricks helped me out a lot. thanks..
Managed to get the rim dished, trued and balanced and decided on a set of Maxxis Holy Roller tyres (2.5") Far less rolling resistance than the Minions I usually run offroad.
Mounting the motor in the frame I came across my first challenge. 150mm dropouts in the bike and 135mm spec on the motor. Lucky for me I had a spare set of 135mm dropouts that suit as I didn't like the idea of shimming out the 150's with washers.
I next discovered that there was a small gap in the dropout where the motor axle has been bevelled.
To fill this gap I noticed that another member had resorted to using split pins cut to size and filed down. So that's exactly what I did. Protects the expensive aluminium dropout from being thrashed out by any axle movement.
View attachment 4
Next up was mounting the brake rotor. I treated myself to something a little bling (nothing to do with the expectation of fire coming out of it). But found that it didn't even come close to lining up with the calliper. A bit of creative washer spacing was called upon. Both inside the disk and between the calliper mounting block. Now it's spot on.
Turning attention towards the batteries, I've noticed a lot of different opinions of Anderson vs Deans vs Bullet connectors but decided to standardise the entire configuration to 5.5mm Bullet connectors so that I can have a play around with different voltages and capacities etc. Soldering up suitable parallel link leads and charging connections etc. Seems to be working OK. Despite some inattentive, Rookie shorts that ended in molten metal on the wall (another story).
Mounting the battery pack. Well for now I went with a seat-post mounted Beam Rack. Seems to be a few of these kicking about. Only trouble was the rear of the bike has so much suspension travel that the rear tyre was rubbing on the rack over the smallest of bumps. Even with the preload wound full on.
Spinning it around forwards is proving to be a viable alternative. And the bike handles one million percent better without that weight hanging over the back wheel. It reminded me of taking a 100Kg Pillion passenger for a ride on the Moto. That's how much it affected the bikes edge to edge performance and turn in. May just stick with it for now 'till a better alternative presents itself. I also think it's kind of stealth with the bag hidden by your body and legs as you blast past onlookers just in time to see their WTF face.
Preliminary tests have given it a 40km range (with a bit of peddling involved to stay warm) and a max speed of 66Kph clocked at the local valendrome.
------------------
Additional notes. I have since gone on to add a pre-charge resistor to stop that awful arcing when connecting the battery pack. Also sick of resoldering new bullet connectors as they don't tend to last too long with that kind of arc. Ended up running with a 5watt 220 ohm resistor that is connected first to allow the caps to fill.
Still needs some fine tuning but pretty happy with result.. And it's been a very enjoyable project. Learnt a lot, and working on other ideas. More will be revealed. I like this E-bike thing! Got my eye on the Hanglider soon.........
Big thanks to all members posting their experiences. Wouldn't be able to do it otherwise.
