New guy excited to be here...

[Sean Solo]

Hey everyone,

I'm not new to forums, but most certainly am to adding motors to bicycles. 

I recently got myself an adult tricycle:


I've since added a custom box:


It's pretty awesome, but also pretty heavy (~60lbs or so).  I got it since I don't drive, and balance issues dictated three wheels.  I actually could have gotten a mobility scooter, but am still able to pedal, so am.
The weight of it makes going up hills challenging though, despite it being a 6 speed, so I was thinking hub motor before I even bought it.
I wouldn't use it except for that and perhaps to get moving at times, and am not really concerned with going fast (15k is plenty quick).

There are a few issues with adding a hub motor to a trike, I'm finding...
The rear axle is larger in diameter than a standard bike, so I was thinking of a front one?  Traction and torque are potential issues there though?

I like the sound of "lightweight" and "zero resistance", so was eyeing the 902...

Anyhow, looking forward to any and all input.

I feel like such a newb...lol

[Bikemad]

Hi Sean andto the forum.

A rear motor would not be suitable for your trike because of the single point attachment, as usually a through axle with dual end attachment is used.

I suggest that the Smart Pie would be a much better choice than the 901 because it does not have any internal gears, and is therefore much quieter under power than the 901, and it can also be used to provide regenerative braking force which recharges the battery slightly.
More importantly, using the regenerative braking to slow down will really reduce the amount of wear on your brakes pads/wheel rim.

The 901 motors are also prone to overheating under sustained load, which is probably not ideal for a heavy trike. 

The Smart Pie is permanently engaged (mechanically not electrically) and therefore does not have an internal freewheel device (unidirectional clutch) to allow it to mechanically disconnect its drive (like the 901 does) but at slow speeds, the Smart Pie does not appear to produce any noticeable resistance to pedalling.

Check out my review on my original, pre-Sine wave Smart Pie for more information.

The later Smart Pie 4  (and Smart Pie 5 with Bluetooth connectivity) are virtually silent under power compared to my original Smart Pie.

A front mounted battery (i.e. in a suitable handlebar basket or rack mounted over the front driven wheel) would help to provide better traction under power on loose surfaces.

Alan
 

[Sean Solo]

Hey awesome!  Thank you so much.   Yeah - I thought about torque issues with only powering one side of the back wheels too...

Great work on that install.  Wow that's cool. 

So another question: I have a band brake for the rear.  Will that matter if I go with a front motor?

Also, what voltage would you recommend I run it at?  Should I swing for the fence, and go for 48v straight away, or would 36v do?

I've only recently got the trike, and there are a few more tweaks I have planned, so barring winning the lottery, I most likely won't be pulling this trigger for a little bit. 

Besides, I'd get it, install it, and it would snow right then.    HA! 

Springtime?

[Bikemad]

The band brake on the rear will not be a problem for a front motor as the rear brakes and gears etc. are independent of the front wheel and will still behave exactly the same.

Yeah - I thought about torque issues with only powering one side of the back wheels too...

As there does not appear to be a differential on the back axle, I presume your pedals (and rear brake) currently only drive (and brake) one of the rear wheels not both, otherwise it would be very difficult to go around corners if both wheels were driven by the same fixed driveshaft. 

It looks to me as if the Right hand wheel is connected to the pedals, and the Left hand wheel is connected to the rear brake. 

If "15k is plenty quick" then a 24V battery would be fast enough, with a 26" Smart Pie, the maximum speed on the level would be:
~15mph (~24km/h) @ 24V
~20mph (~32km/h) @ 36V
~25mph (~40km/h) @ 48V

You would need to decide how fast you really want to go, and also take into consideration how fast you can legally go.

If you use a higher voltage battery, the controller can still be adjusted to set the maximum assisted speed (and available motor power).

Alan
 

[Sean Solo]

You are mostly correct.
The right side wheel does in fact "drive" the trike, but the brake is more towards the centre:

It's not "powerful"; more just slows me down.  If I want to "lock 'em up", the front linear pulls could send me over the handle bars...lol

The left rear wheel just spins freely... (likely what you meant anyway - I'm not very well versed in such things).

No, it's not the top speed that I'm concerned with at all.  30kph would freak me out (plus trikes do handle slightly differently - takes some getting used to).   It's the amount of actual power available though, and hill climbing ability that I'm most concerned with. 

The bike (trike) already weights a lot.  Add me, and we're pretty much already at the 200lbs mark.  Also, has 24" wheels.  Both would affect top speed, I believe...
I just need to be sure that there'd be enough power to move the thing...lol

When I walk, I hobble along at 1kph avg, so 15kph seems like lightning.

If a 24v would provide ample torque, then for sure (batteries are not inexpensive).

I BELIEVE it's 32kph max on the street here (Ontario, Canada) anyway.  I'd likely never go there.

I'm truly very grateful for the advice, Bikemad.  I'm presently watching Smart Pie vids on YT.  HA!

Again; I really know very little about electronics and bicycles, but I do have a science background, so get physics, chemistry, and math.   I feel like I'm in the a good place to learn as much as I can though, and waiting until spring would allow me to stagger purchases (LiFePO4 batteries are up there eh?)

[Pwd]

Welcome, and nice trike!

For hill climbing etc.. the Magic Pie Edge would provide more power than the Smart Pie. (18 amp controller vs 25 amp controller). The Magic Pie 5 would provide more power yet again. Same controller rating of 25 amperes but larger motor.

Last time I checked the legal limit is 32 km/h and 500W max power. Actually, here it is:
http://www.mto.gov.on.ca/english/driver/electric-bicycles-faq.shtml

All the Pie controllers *can* be programmed to limit speed.

You would get the most torque with a 48V battery; but as you've noticed; they are much more expensive.

[Sean Solo]

Last time I checked the legal limit is 32 km/h and 500W max power. Actually, here it is:
http://www.mto.gov.on.ca/english/driver/electric-bicycles-faq.shtml

All the Pie controllers *can* be programmed to limit speed.

You would get the most torque with a 48V battery; but as you've noticed; they are much more expensive.

Hey thanks pwd!

Well, that rules out the 1000w one...lol

See though?  MP now.
That would solve a bit of the weight issue too, wouldn't it?  Meaning: It would add slightly more weight to the front wheel, and therefore assist in traction (?)

Yeah - batteries - WHEW! 

Here's an "upbeat/uplifting" vid I made last week...ignore the end.
http://www.youtube.com/watch?v=etKjcZSf8Zc

Where I live (Welland, ON) has a great path system as well.  I watched a video this morning (it might have actually been a Gary one) where the paths in his community were lauded.

[Bikewrangler]

Hi. I Live in mountainous Norway with steep hills at every turn. I`m somewhat disabled so pedaling a lot is not in the cards. I have tried the 24. 36, 48v (now moving
to 52v) batteries. Rule of thumb "the bigger the better". I would get a Magic Pie5 with a Bluetooth dongle. The 48v rack battery (you can expand with another one later to double your distance).
Find a way to mount on the right side. Then program the controller (via very nice android app) to a comfortable/legal limit. The bigger the battery the less strain and less heat is put on each battery cell. This improves battery life a great deal.

[Sean Solo]

Hey right on Bikewrangler!

Thanks for that.   Great info, that I really would have no idea about otherwise.

I'm going with 48v to start, and I like the looks of the MP Edge...

There aren't many hills here, and I do still want to pedal a lot of the time. 

There are a few though, and a few spots where some power would be nice.

I'm currently staring at my bike, thinking of battery placement...lol

[Bikewrangler]

I have not tried the edge, but I hear great things especially when it comes to
torque help up a hill. The edge can also easily be programmed via app.
I`d find a spot close to the mid/front. It gives me "comfort" to mount the battery plate with thick rubber gasket/seal between bike and battery plate as a shock absorber.

[Sean Solo]

I`d find a spot close to the mid/front. It gives me "comfort" to mount the battery plate with thick rubber gasket/seal between bike and battery plate as a shock absorber.

Oh for sure.  The battery MUST be solid.

I might mount it towards the rear actually.  I know, I know...weight at the front...

We will see.

I'm excited to add this now.  I've been building it in my head for days now...lol

[Bikewrangler]

Be sure to add some pix when you are done

[Sean Solo]

Be sure to add some pix when you are done

Oh you bet.

I'll most likely do a build video.