Full-throttle's 1st

This is my first e-bike, built as a reliable everyday commuter.

I'm currently (slowly) working on a different concept which can be found here: http://endless-sphere.com/forums/viewtopic.php?f=6&t=15066

What it used to be
Bought the frame as a replacement to the cracked DH frame. I picked it because it has a long top tube (22.5") and short seat tube (15.5") - perfect for aggressive XC (the pannier mounts look a bit odd though on a DiamondBack Race series). Soon after I started commuting on it, so the fat knobbly tyres gave way to slicks, 5" suspension fork to a rigid and DH cranks to road double ring ones. Who knows what it would have ended up as if I didn't get a proper road bike.
Some time later, the pannier mounts came in handy for touring and I took the bike to NZ and Perth as well as a couple of mountainous tours around Victoria.
I only raced it once, and what a race it was: Otways Odyssey - a 100km MTB marathon!
Later still it became a singlespeed MTB..


Ver 1.0
Mark_A_W is the pioneer of the e-bike revolution at work. One morning, rather tired after riding in I asked him if he knows where to get a motor. He quickly offered me one of his - a rear geared bafang (no idea what model, prob s a 150mm), and quite cheaply too. He even threw in a small 6FET lsdzs controller and a busted throttle. All I needed was a battery and a bike.
The little controller used to be a 36V 10A and it didn't take long to mod it to 48V by replacing the caps and the main regulator.
The battery I got from V-power (never again) although it still working. And the bike - well.. why not give it another life!
So it began. I opted for 700c x 28 instead of original 26" to maximise the speed. Needless to say, the bike happily accepted bigger wheels and the top speed increased from miserable 25kph (@36V) to a more respectable 37kph (@48V). I've set it up as a singlespeed (150mm axle worked great with that, became a standard 135mm) and still think it makes a lot of sense for an electric bike.
Initially I had the batteries in a tool box at the back (those pannier mount came in handy again), but soon bit the bullet and repacked the cells inside the main triangle together with the little controller. So soon in fact that I don't even have a picture of it.

Ver 1.1

This setup got me through the winter, clocking 4,144kms. It weighted just under 20kg and had great handling.. but lacked response and comfort because of its small controller and skinny wheels. Said that, the bike kept up with Adrian's 408 48V Headways and Mark's 9C 60V Headways.. until it got to the top speed..
I could not fit any more batteries into the frame and I wanted a stronger motor and wider tyres, so I was looking into getting a new motor. My first choice was a BMC V2-s, but the cost was quite high, even if purchased directly..

Ver 1.2
After some research I purchased BPM code 13 from bms-barrery/ecitypower and a 12FET sensorless controller directly from lsdzs.
My first review here http://endless-sphere.com/forums/viewtopic.php?f=3&t=12582&start=15#p199870
I really like this combo, despite the usual phobias associated with sensorless it works great: smooth and torquey startup, responsive, efficient, operates at sub-walking speeds, grass and gravel burnouts, wheelies. Top speed is around 40kph on the flat w/o pedaling, 30kph w/o pedaling up 13.5% (35kph w pedaling). I'm light though.
Up to now it clocked close to 3,000kms.


Daily trip (one way)


Edit: added daily trip figures [metric (imperial)]

• 
  Max voltage 58.4 V
  Min voltage 48.1 V
  End trip voltage 52.1 V
  Total discharge 5.5 Ah
  Total energy 284 Wh
  Max current 26 A
  Max power 1330 W
  Total distance 23.3 km (14.6 mi)
  Average speed 32.5 km/h (20.3 mi/h)
  Total time 43 min
  Ave energy/distance 12.2 Wh/km (19.5 Wh/mi)

to be continued..

Hey, that looks familiar!


It's a really nice bike, that BPM motor is really torquey, a pity the axle is too narrow for my DH Team frame.


Actually I wasn't the first at work, the guy with one leg (he had an artificial leg) rode a big heavy lead acid batteried off the shelf thing.

Hey you make me sound like a bastard giving you a busted throttle...it was only meant to allow you to test the system! I did give you the disc and disc adapter


Have you got a picture of the repack battery pack before you taped it up?

So.. after nearly 2 years of 2hr-a-day, 5-days-a-week commute (23,000km give or take) time has come to retire this frame.

While I was planning to change over to a new frame soon, going trough an intersection at dusk and not paying enough attention made me speed up my decision

Consequently a bent RHS drop-out and crank, bent brake rotor, snapped motor axle and chain tensioner, severed motor wires and a couple of scratches. Luckily I was unharmed apart from a bruise on the shin.

Ouch.

Glad to hear you are okay. What happened? Must have hit something pretty damn hard.

[EDIT] Oh, and photos. Otherwise it didn't happen.

Snapped motor axle.....ouch..

Glad you are ok!

adrian_sm said:

What happened? Must have hit something pretty damn hard.

Click to expand...

I don't want to go into details, lets just say I unexpectedly appeared in front of something rather large and fast traveling.

adrian_sm said:

Oh, and photos. Otherwise it didn't happen.

Click to expand...

Yeah sure, that what you really care about
Just kidding
Thanks for your concerns guys, I'm ok. It wasn't the first nor the worst.

Now that day-light savings has finished, riding home @ 5-5:30 ish is really bad. The sun is right in your eyes the way we go home. I have been thinking of leaving work early or late to avoid it. I really don't want some car with the sun in theirs eyes running me over.

Anyway. Really glad to hear you are okay. From the sound of it, things could have been a lot worse.

Take it easy.

Adrian

The damage was more than I originally thought: the frame is actually bent from impact. Rear rim is cactus too.

Borrowed a BPM core from BenMoore untill the replacement axle arrives - thanks Ben!

Put together a new battery pack using salvaged Headways and my own BMS

Made hidden torque arms

Went for a ride - love it! The feel of steel. Super quiet.

Very neat build. Looks like you could convert it between electric and not pretty quick if the need arose.

Hi Full-Throttle,
How does the BPM Code9 compare to the HS3540 in your Bomber? I know you don't run the same power on both, but both motors have similar RPM/V , weight isn'y far away either. So how about torque and efficiency?
I have the same BPM on my commuter, running 12S2P Lipo, and I am quite happy with it. Have to build something similar for a friend, so I was wondering if it was worth trying the HS3540 instead.
Thanks
Martin

HS is nearly double in weight, doesn't freewheel and will probably have less KA (torque per amp)
It will take more heat, no gears to strip and the axle is not as fragile.

Efficiency and Kv are similar as you said.

Nice commuter bike FT

I have a sensorless BPM from Ecitypower, but a code 14 I think, tops out about 36-37kph on the flat with 12s lipo. As mentioned in my PM, I'm now looking to pick up one of Ben's sensored BPM to slot into a dual suspension Giant. Any advice on which code to use? looking for a top speed of 40kph and ability to tackled the occasional steep rocky track with some pedal assist.

Thanks Brian,

A code-12 or code-11 will be fine. The loan motor is a code-12, so if you have any questions now is a good time to ask

Re: off-roading:
The axle is not well designed - the right section in the picture is unsupported AND there are 3 stress concentrators right at the point of the most stress: circlip, exit-wire hole and keyway slot. It is also hollow.. No wonder it snapped off. On closer inspection it appears to have partially cracked before the accident. All those speed humps I threat as jumps

Another support bearing closer to the RHS dropout might just be what it needs.

A cassette type freewheel would do the trick, but it is next to impossible to do... would be great, RHS bearing right next to the dropout. Unfortunately, this means also a major redesign.

FT, thanks for the tip on the axle. I'll keep an eye on it for cracking and see how it goes. I'll see if can come up with some additional support (maybe a aluminium sleave and bearing), but if it starts to go anyway I always can get a MAC later on. Do like how the BPM is put together, so willing to test if it can take the punishment.

No specific questions just yet, just interested to hear your opinions on how it goes, speed vs climbing etc. Main reasons for going with the BPM over a HS35 or 9C is better torque at low speed and lighter weight for lifting the bike onto the car bike carrier and over the ocassional gate or fence.

full-throttle said:

The axle is not well designed...It is also hollow.. On closer inspection it appears to have partially cracked before the accident.

Click to expand...

I wonder how the design compares to the 9C. Any idea? I don't mind cracking mine over a jump, but would hate for a surprise at high speed...

Glad you're OK. New one looks nice.

9C has bearings on the sidecovers much closer to the axle ends - so you got nothing to worry about.

One easy way to add extra support on the BPM would be a bearing fitted to the inside spline of a multi-cluster screw-on freewheel. The freewheel would still be removable by removing the sideplate and knocking the bearing out. I just cant' find any bearings with 15mm ID and 22mm OD.

adrian_sm said:

Looks like you could convert it between electric and not pretty quick if the need arose.

Click to expand...

That's the idea!

Rode it yesterday without battery/controller and couldn't believe how well it rolls along. I'm aiming for the change over to take 5 minutes or less.

full-throttle said:

Rode it yesterday without battery/controller and couldn't believe how well it rolls along. I'm aiming for the change over to take 5 minutes or less.

Click to expand...

I would never have considered trying to switch between electric and non-electric for either of my hub motor builds. It was just way too much hassle. So to get it to about 5 minutes is awesome. But not quite as quick as installing or removing my Commuter Booster. :lol:

A bit of trivia today:

How is this (the connector) related to this (burn marks)View attachment 1 and this (Electronics Resource Group Smoke Award)

Hmm. Let's see I guess either melted connector causing short circuit, or the wet weather helped...

full-throttle said:

A bit of trivia today:

How is this (the connector) related to this (burn marks)

Click to expand...

pre-charge resistor plug that shorted out as you plugged in it ?

The connector is a DC jack that I use for charging.

The centre pin corroded from all the riding in the rain, so when I plugged the charger for the n-th time it snapped and shorted. There were nice fireworks and the sheet cover over the Bomber caught fire. The connector blew clean off leaving a couple of pieces of brass still glowing on the ground.

Then someone decided to nominate me (in my absence) at the monthly meeting for the 'prestigious' award.

The moral of the story: electricity and water don't mix. There's a nice plastic cap over the connector now

How does the ss gearing work with ebike?

Great!

Depends who you ask. Most if not all of those who'd tell you otherwise have never tried it.

I'm posting a short video of a typical morning commute - couple of intersections, traffic, the usual stuff..

Running BPM code-12 on 48V/30A - 40kph on the flat, 45kph with pedalling. 48/16 ratio, 26" x 2.35" Schwalbe BigApples.

[youtube]5j5EOJDZkoQ[/youtube]