Best smallish high torque motor

[Jimbo]

Hi guys,

So, collective wisdom, what is the best smallish motor for a high torque setup? Im not too worried about top end (25 would be cool) but i want power wheelies.

Clearly if i buy a gargantuan DD hub and throw 100's of amps at it then I will have a high torque beast, but i want to try and keep the weight down.

I have a Crystalyte HS3540 running at 50A which is ok, but its hardly a wheelie monster. I don't want to go any heavier than the HS for the motor.

Do i buy a beefy controller and run higher amps?

Or do i buy a MAC 12T and run it at a high enough voltage to give 25mph? WIll this get me into power wheelie territory on a 26" rim or will i just fry the motor?

I could go to a 24" rim i guess.....Other options?

All suggestions and experience appreciated!

 

[MadRhino]

Lace your HS in a smaller wheel and feed it 10Kw. That will give you what you want, but you'll have to monitor temp to know when to stop abusing it.

 

[dogman dan]

About as small as you can get and have that much torque. Lace it 20" and put it on a bmx frame.

Or you could build a wheeliemobile the way I did. Took a 24" bmx, put a 5304 24" rim on the back. Then put a shock fork and 26" wheel up front.



The extra 4 inches or so of lift on the front end displaced the balance of this bike so bad, 500w of throttle would lift the front wheel. You know how when you pull a wheelie, there is this point where it will not try to set back down so hard anymore. This bike was at that point just sitting there. It was kinda fun to ride, in a sketchy way, since you only intermittently got to steer. Fun in soft sandy roads ass and throttle steering it. When you really needed to steer, you'd charge the bars with all your weight. I only had a 20 amp controller at the time, thank god.

The pic, btw showed it in a test ride. Later I had 24v ah of nicads in the frame, and 24v more mounted on the bars. Still wheelied with ease, but now it took all 1000w.

 

[Timma2500]

My girlfriend's bike has an 8t Mac in a 24" rim and wheelies well @ 2kw, i'd go for a 10t in a 26" rim on 12s lipo and enjoy the torque / light weight





Paul

 

[hydro-one]

Mid drive. one of john from cr's mini monsters in the frame. high voltage. air cooling

 

[atom1025]

10t mac, 26"wheel, on 15s 35 amps, 2000w makes the front end feel preety light. Its enough torque to make you take caution when accelerating but not enough I would call dangerous. Great blend for a daily rider. Id worry bout gears and clutches if its gonna take repetitive abuse.

 

[999zip999]

You could always go back to lead and hing it off the rear, Like the wheelie dragsers and all it can do is wheelie. Weeeee. Wheelie's are off balance. Of power and weigh

 

[Jimbo]

Guys this is all good, thanks for the ideas.

Ideally id like to go with a mid mount as this will be a proper trail bike and i want to keep the unsprung weight down but i've not seen a decent retro fit kit yet. Hydro - what are the Mini monsters like?

I considered buying a Lyen controller for the HS and shoving 100A down it, that should pick up the front nicely but it'll be way inefficient at low speeds and spank the batteries. I do want some decent range here so for efficiency I'm thinking a MAC 10T running 12S and 24" wheels as suggested by Timma.

Question though - I used to have a MAC 6T with a 25A controller and it was LAME in the torque dept...will a 10T on 35A cut the mustard? I live in Dubai and want to ride in the mountains, its pretty steep! I want to go with the 12T but then I'll need 18S of batteries, which is more than i really want to be carrying.

decisions decisions...