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My Outback E-board Project

I wish I had waited, I picked up the pie 3 for my Dirtsurfer, but never got around to completing it. It now looks to be a winter project. Good to hear you have your Outback running, I never did get back on mine. Pretty much lost interest on it, maybe your field reports might bring that interest back.


zerogee said:
Golden Motor Smart Pie 4 with the new Vector sinewave controller on its way. So, I can finally get started on this thing. :D
http://www.goldenmotor.ca/products/Smart-Pie-4-%28VECTOR%29-12-Inch-Front-Conversion-Kit.html
 
It was a bit too bumpy of a ride on the grass and I think the battery makes it too top heavy for surfing berms. I decided that I need more time on pavement getting used to the throttle and the ride before hitting the grass again. I took sme air out of the tires to smooth out the bumps and improve traction. It is an improvement. The range is about 30km on "hilly" terrain. Here's some of it in action...

e-Outback on the lot: http://youtu.be/uyMaEkHo7hQ
e-Outback on the trail: http://youtu.be/t-eEnsfrp44
 
Looks like fun! Have you tried unpaved roads yet? What is the max speed with your setup?
 
Yup. I have kited with the board on pavement, hard packed gravel, loose gravel and grass. I have also downhilled with it on pavement, hardpack and grass.

Like those activities the e-board version becomes more difficult to maintain control on rougher surfaces at speed (like bouncing you off) and wet grass or loose gravel is just like ice. Long grass can stop you dead.

The worst surface so far has been a soccer field well used in the rain and dried. Most hardpack trails /roads have not been that bad. Taking just a couple psi out of each tire has improved both traction on looser surfaces and softened the ride.
 
Max speed with current settings has been just under 24kph. Fast enough to keep up or overtake cyclists or get into trouble. :D

I broke 30kph on some of the downhills on the trail in the video.
 
Sounds good. Nice that you have tested all those surfaces already:) I am currently riding those with my MTB and was worried about how well the single drive wheel compared to my two driven ones would do. Do you think traction could be increased with a different tire profile?

I got my hands on an outback board and hope to follow your example :) I am looking for alternate motors and batteries right now, just to have some options. Have you considered putting the battery between the two steel tubes at the buttom of the board?

Is there an option for more speed on your setup? My MTB is capable of 34kmh which I rarely use but still like the option of.
 
Damn, I really like how silent the MP4 is. Looks fun, I will have time this winter to work on my projects. Making board sports a priority this winter.
 
furp said:
Sounds good. Nice that you have tested all those surfaces already:) I am currently riding those with my MTB and was worried about how well the single drive wheel compared to my two driven ones would do. Do you think traction could be increased with a different tire profile?

I got my hands on an outback board and hope to follow your example :) I am looking for alternate motors and batteries right now, just to have some options. Have you considered putting the battery between the two steel tubes at the buttom of the board?

Is there an option for more speed on your setup? My MTB is capable of 34kmh which I rarely use but still like the option of.

I was pleasantly surprised at the amount of torque this single wheel had. I had to dial the acceleration down so it wouldn't kick me off on pavement (plenty of traction on take off) and it would spin out on the gravel (which happened to make for a friendlier take off).

Where it loses traction is sideways on any surface when carving hard (tight). The back wheel breaks loose. This is least noticeable on pavement and most noticeable on loose gravel or banking hard on a berm.

The board did this even with the knobby tire on the back and a kite. I loved that feeling though. But I had the kite to support me back then so now it feels different. But I see improvement on pavement already.

It could be just a case of more practice to get comfortable again. Could be I need to try the knobby tire. Could be I need to mount the battery under /between my feet. Maybe all of the above.

Loose gravel always felt like ice though even with the kite and knobby tires.

I had a hard time finding a hubmotor that had power and was narrow enough to fit into my frame. Most were way too wide or I was not able to get that dimension. The Smart Pie has an internal controller so it was one less thing to try and mount under or on the deck.

I am definitely considering splitting the pack, case and all and mounting as much as I can under the deck inside the frame and the rest on the deck between my feet. I think this will give it a much better center of balance and more stealthy look.

There are some settings on the controller I am looking into for speed adjustment. Not sure if they will work or if they will be hard on the motor /battery.
 
kfong said:
Damn, I really like how silent the MP4 is. Looks fun, I will have time this winter to work on my projects. Making board sports a priority this winter.

I am having fun with it.

It sure is quiet. There is more wind and road noise than motor noise.
 
The orange frame some mild steel pipe?

If it was me I would have redesigned the basic frame to have integrated mounting trays for the batteries below deck. Make it slightly wider. One could even widen the rear hoop for a hub motor wheel and disc brake. Should not be too hard to have an exhaust fitment centre bend it. Then basic arc welding to fit all the pieces together. Add mounts and brackets where you want them for the motor controller etc. Carry over the deck and steering rack
 
Ya, I went the most plug n play route.

I did entertain the thought of modifying the frame to accept a wider hubmotor. But I decided that I didn't want to wreck the board in case I was not happy with it as an eboard I could return to using it for kiting. I didn't want to add more weight to an already heavy board too. I was also concerned with it being done right and changing the strength and/or geometry of it.

I could have also gone the RC route with chain drive that required more fabrication but would have left the board mostly factory. But I had a hard time getting the small stuff I needed to fab done right as it is.

I did explore RC Lipo to fit entirely inside the frame on a tray under the deck. It is possible. But once again I chose the quick and dirty, LiFepo4 pack I have. The price was right and I didn't have to wait for it. I wasn't comfortable with storing and maintenance of Lipo over the winter months too. I might explore that in the future again after some battery experience.

If I split the current pack and move it onto and under the deck there should be room for a small disk brake if I decided that I could use one.
 
Starting to get the hang of it. Taken it offroad.

http://youtu.be/a3K60R2QTuA

Turns out that the lack of traction (skipping) issue on hard carves was partly caused by the tire bead that was not properly seated. The wheel was slightly egg shaped. :roll:
 
Looks fun! I got myself a board, too and am looking for the right setup. Will go the custom battery under the deck route. Not entirely sure about the motor yet. Would like a little more speed than the sp4 offers and got recommended a bafang motor. Would require an extra rim and spokes tho, so might add a lot to the cost.
 
I did look at getting the 12.5" Front Smart-Pie 3 with external controller. I was going to set it up with the GM external controller it comes with to see if I could get it to work. Then for more speed upgrade to a controller that could handle 60V or even 72V. I was able to source 72V 5000 mAh of Lipo that would fit inside of the frame under the deck. The controller might of fit into the spot under the deck at the rear. If not, then on the deck or over the wheel.

It didn't look like many other hubmotor conversions were compatible (extremely short spoke length and poor angles) or available in anything smaller than 16" or 20".

Are you considering modifying the frame to accommodate a larger wheel?
 
zerogee said:
There are some settings on the controller I am looking into for speed adjustment. Not sure if they will work or if they will be hard on the motor /battery.

There was a PAS Ratio setting that I thought could be set to an "optimum setting" if you didn't use PAS because there was no way to disable PAS. But it is just ignored if you don't have PAS.

I thought that I could tweek the continuous and peak amps. But they are already default to the max the controller can handle.

I am bumping up the Max RPM to see how far it will allow. Started at 360. The software will allow 700 and the controller will take it but I could not see much difference. Trying small incremental increases to see what the max speed will actually be. The data sheets for older smartpie show 380 RPM Max. So trying 380. Will try 400 after that if I see an increase. And so on until I see no increase.
 
Yeah I am worried about the spokes as well. But modding the frame is no option for me cause I dont have tools or skills for it.

Will the sp3 front work with such high voltage?

Maybe increasing the max RPM will give enough extra speed to make the sp4 an option for me. Make sure to log it!
 
Its my understanding that the SP3 can handle the voltage. However, as with any mod like this care should be taken to make sure your battery, BMS (if used), motor controller, and motor all have a compatible continuous /peak amps. Or that the controller can be programed to match the battery, BMS, and motor.

I tried testing different RPM settings around my home using a GPS to measure speed. I got some top speeds that looked possible, lower averages, and unusually low lows with each run. I suspect that the irregular readings were due to weaker signals because of the huge tree canopy and houses. The top speeds may have been just spikes?? Also the temperature has been sub zero lately and that seems to have affected the battery capacity a bit. I have been trying to get to the same wide open trail I got my initial top speeds from but not sure now if I will get reliable readings due to the cold. Snow flurries at this time too.
 
Did you experience higher max speed than before? Theoretically increasing max rpm should increase max speed, at least on long flats. Would be really nice if you could squeeze out more speed of the motor.

Have you seen goldenmotor.com? There are some data sheets for the motors that might be interesting. However, I can't find the version you got on their site, bike motors start at 16" and the only 12" one is for scooters and too wide for the outback board.
 
It did seem slightly faster each increment. The 'speed spikes' also happened to be incrementally faster but was not even close to the average speeds like with other times when I first determined its top speed. It did not seem to get any faster after 400 RPM (no more speed spikes). Likely does not accept higher RPM for 48V. The battery lost capacity faster but I can't say if that was due to the cold or if it was trying to go faster. If there was indeed an increase it was marginal. If I believe the speed spikes its top speed is just over 26kph (have doubts).

Hmmm... looks like every GM website has different offerings. I got my stuff at Golden Motor Canada. Looks like they still have my motor as well as SP3s with external controller.

Also Most if not all rear hubmotors will be too wide to fit inside the frame.
 
Hmm too bad. Yeah, we are limited to front motors. The real problem is to find a motor that has an integrated 12" rim, so no additional 100 bucks for rim, spokes and lacing if it even is possible. Maybe I should have looked for a dirtsufer instead, but those dont have space to mount batteries. Wish the 16" sp/mp version would fit the outback, it looks really cool :)

Edit: Just found these at uumotors: http://www.uumotor.com/shop/hub-motor/12-inch-250w-electric-hub-motor can be up to 48v 350w but sadly no rpm stated
Or this one (but only 8inch, could make for a weird ride): http://www.uumotor.com/shop/hub-motor/high-speed-electric-scooter-motor-brushless-40km-h-36v250w claims 40kmh..
 
I came across the 12" one but I dismissed it as being 'weaker' than the smartpie. That was before I knew that the smartpie could be overvolted. Perhaps this one could be too?? I was not sure if it was a sensored motor either. I needed it to be sensored.

The 8" motor... I have seen an Outback with smaller fatter wheels alround. The guy did it for more float for kiting on sand. These guys offer front nondrive wheels too. You might need to replace the bearings to fit the Outback front axles. The motor is unsensored but they say they can sensor it for you too. Concerned about the low amps and low torque rating of this motor though??
 
From what they state, that one should only by about 50w weaker than the sp, might not be that much. What interests me is the max speed, I posted a question on their site.

Overvaulting seems like a bad option for me at least, since I would like to get a battery that I can use on a 48v bike should I not use the board any more.

I was also looking at this motor: http://www.uumotor.com/shop/hub-motor/12-inch-gearless-brushless-hub-motor-48v-500w looks beastly! They got a video on their site on this motor.

The dropout is stated to be 145mm which might be achieved with very little modification on the frame. The pieces holding the wheel are welded to the inner side of the 3cm diameter steel tubes. Maybe by removing them and welding them back on the outside of the tubes, about 6cm dropout size could be gained. When welding them back on on the 'bottom' of the tube, 3cm could be gained to have about 155mm dropout. Will have to see and remeasure and ask someone who actually knows something about welding..
 
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