Hub motor selection guidance: 3kw unbranded vs 5kw QS

Get all your technical information about electric bikes here.
2WheelsMovesTheSoul   100 W

100 W
Posts: 183
Joined: Oct 17 2017 12:59pm

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by 2WheelsMovesTheSoul » Oct 29 2018 9:43am

Bg-electric-cycle wrote:
Oct 28 2018 11:43am
What front forks are you riding on?

DNM USD-8's you can see brake install here -> viewtopic.php?f=1&t=93082&p=1362844#p1362609

I noted the double disc brake. Overall very nice build. :bigthumb:

Aw... Shucks. :oops: Thanks.

2WheelsMovesTheSoul   100 W

100 W
Posts: 183
Joined: Oct 17 2017 12:59pm

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by 2WheelsMovesTheSoul » Oct 29 2018 10:27am

Chalo wrote:
Oct 28 2018 7:32pm
2WheelsMovesTheSoul wrote:
Oct 24 2018 5:27pm
LOL, my EEB is already 148lbs with a 20s14p pack, 18" moto wheels, tubes and tires. Probably end up closer to 165lbs once I get my 22s19p pack.

If you ain't jumping this bish, get the QS motor, I've pushed over 10k thru mine and with the FF+hubsinks and it hits 60mph with ease.
Who did you find to insure it? Was it hard to get a title for it?

I see where your heading Chalo. Nobody insures it and there is no title. Not interested in either.

I didn't build this so I could ask rich bureaucrats for permission to ride it.

SmashBot   1 µW

1 µW
Posts: 2
Joined: Feb 03 2018 11:03pm

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by SmashBot » Oct 31 2018 2:24pm

You really ought to go to a controller capable of more amps if you are considering the QS 205 V3. I would step up to atleast a ASI BAC 2000 controller to get the full potential out of that motor.

Yermommy   1 W

1 W
Posts: 57
Joined: Mar 17 2018 1:18pm

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by Yermommy » Oct 31 2018 9:19pm

I purchased a qs205 3.5t in a 17" wheel on 10/20/18 from em3ev. I was told it shipped 10/29/18 with 3 day shipping so I'll let you know when I get mine.

Yermommy   1 W

1 W
Posts: 57
Joined: Mar 17 2018 1:18pm

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by Yermommy » Nov 07 2018 9:52pm

Got my wheel yesterday:

Image

markz   100 GW

100 GW
Posts: 7420
Joined: Jan 09 2014 11:38pm
Location: Alberta Canada

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by markz » Jan 07 2019 8:19pm

The mxus 3kw is not that bad, perhaps I am just used to it.
Carrying the 3kw up the stairs.. well :lol:
When was the last time you did that?
I cant remember if at all.
The leaf 1500W is a nice motor, if I wanted a lighter, more nimble ride for fast single track, thats the motor to have!

neptronix wrote:
Oct 19 2018 12:04pm
10lbs more is alot when the bike is already 70lbs.

This is why i'm a fan of the leafmotor 1.5kw on about 4kw of peak power, tuned to do 2kw continuous ( it can handle it, it's underrated ).
I could still pretty easily flip the bike over for a tire change or carry it upstairs with a few grunts along the way :lol:

Some people claim that hubsinks and ferrofluid on such a small motor increase it's continuous capability to 2.5-3kw.

The mxus 3kw ( or one of it's clones ) gets you 2 more lbs and a more likely realistic rating for the 45mm hubs is around 2500w continuous.. add ferrofluid and/or a hubsink and you are up to meeting a 3kw continuous requirement.
( yes, i owned a leafmotor and a MXUS 3kw.. the 3kw was very underwhelming. Later found out that the 3kw rating was done in a 20" wheel, which is a real cheater way to do it. )

Otherwise if you want low weight and high power, RC motors with dual stage reductions to the rear are the only way to go. But those setups are kinda exotic and still in the 'fabricators only need apply' stage at this time.

User avatar
neptronix   100 GW

100 GW
Posts: 13942
Joined: Jun 15 2010 5:56pm
Location: California refugee living in Utah, USA
Contact:

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by neptronix » Jan 07 2019 8:35pm

Moving a bike up the stairs frequently and flipping one upside to change a tire every ~10 miles is how i learned to appreciate power density in motors, and have persistently sought out the most efficient and light e-components ever since. :lol:

But not everyone has the same conditions.
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

999zip999   100 GW

100 GW
Posts: 8877
Joined: Jan 10 2010 1:40pm
Location: Dana Point So. Cal

Re: Hub motor selection guidance: 3kw unbranded vs 5kw QS

Post by 999zip999 » Jan 07 2019 11:27pm

I have Muxus 4t and 18 fet powervelocity 80v 20ah of A123 @ 70amps. Good fun motor. I tried going lighter edge 1,500 watt and its just to small Melted.

Post Reply