BRUSHED MOTOR MID DRIVE

[AdamC]

I have this kit on the way
https://www.amazon.com/gp/product/B01CL2NWUY/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

its 450 watt brushed mid drive, throttle operated kit. I went back and forth a lot on which bike or kit to purchase.
I decided on this one based on price, simplicity and the ruggedness of brushed motors. ( not as much electronics )
I also have a 48v 13ah battery on the way-

is there a formula that can tell me what the theoretical top assisted speed would be? just out of curiosity..
also, does anyone have some experience with similar kits?

 

[harryS]

Yes there is a formula. You take the rpm of the motor at its shaft and use the gear ratios to figure out how fast the rear wheel turns in rpm. Convert that to MPH. This is no load speed.

I would estimate real world 24-28 mph with a 26" wheel, if you have a strong battery and a powerful controller, and if the motor works right. Amazon feedback ain't too good for your kit. Hope it works.

You can google GNG electric mid drives on youtubeand see few guys in that speed range.

Take care. Going fast isn't hard. It's about stopping that keeps you and the world safe.

 

[AdamC]

Yeah its hard to gauge with only 1 review but seems like a pretty basic peice of kit. I oike the simplicity i would prefer a thumb throttle but like the display on the twist throttle ... its trade off. Thanks for the video link!

 

[J.R.]

@AdamC, it would appear this is the 30 amp controller that comes with that kit.

https://www.amazon.com/gp/aw/d/B01D...SY340_QL65&keywords=l-faster+ebike&th=1&psc=1

I say appear because it's difficult to find a lot of detail. If that's the case, depending also on the battery pack, your speed will likely be at the upper limits Harry noted. Maybe higher!

You probably know this, but the same seller offers a cadence sensor, thumb throttle and other parts.

https://www.amazon.com/gp/aw/s/ref=is_s_ss_i_2_8?k=l-faster+ebike&sprefix=L-faster&crid=DTSEW00JG56K

Having seen those types of brushed motors before, I'd bet it's the same motor used on millions of electric scooters from China. It's an interesting idea for an inexpensive ebike. I hope you keep the forum updated on your progress. For a variety of reasons these days, there's a lot of ebike bargain hunters.

Good luck with the project!

 

[AdamC]

Email received from seller- its on its way- it is a 30 amp controller
the battery I have on order is continuous 25ah with peak of 50.
I think that should pair well , I am thinking a bit f a buffer to prevent over heating.
But electronics is witch craft so who knows,

 

[harryS]

Just curious on the price of the kit. I'm guessing around $149?

 

[AdamC]

225 plus shipping

 

[AdamC]

I have everything wired up and everything seems to work. need to get pedals on and brakes hooked up and everything all cleaned up before its ready for a test ride. I wil post pics and maybe a video when she is finished

 

[AdamC]

I took it for a very short test run this weekend. pulls hard up a short steep hill by my house and not very load at all.
I need to replace the old chain that came on the bike from the bike co-op and attach the rear brakes. both come in today.
so far it seems like a decent kit especially for the price.

 

[harryS]

Good to know you got it working. Gotta have brakes.

Any concerns about the motor bracket being tough enough to last?

 

[AdamC]

No it seems like pretty thick material around an 1/8 in thick. inexpensive steel but stout enough I would believe

 

[AdamC]

Everything is done , the freewheel seems to be skipping under human power as well as epower, will try a different freewheel and hopefully that solves my problems. the chain is new. otherwise when its not skipping the motor pulls well uphill, the supplied headlight is bright and the motor noise is barely there in my opinion.

 

[harryS]

You do have to make sure the chain length is correct. Going to the new front sprocket which is probably smaller than the old one means the chain will need to be shorter. And the chain is different for a 9-10 speed gear set vs the 6-7 speed gear sets.

Sounds good, and it must be warmer where you live.

 

[AdamC]

I replaced the freewheel and it resolved the problem, today i will do a hilly ride and see what my range is looking like.
I,ll post a photo as well

 

[AdamC]

maiden voyage! 13 miles 50 minutes with 1100 feel climbing yesterday
17 mile morning commute with 1500 feet of climbing in 1hr 10minutes

losing the Schwalbe marathons plus tires, too much drag for such a long commute. so far thrilled with the
kit, and the bike I got from the co-op is supremely comfortable. I have some fenders and a controller box coming via amazon.

I will post a photo tonight

 

[AdamC]

The motor drive chain dropped off twice die to the idler pulley that the kit came with- really bad design. but there was just enough play
to remove a link and install a half link. now I have good tesion without the pulley- I email the seller to sugget it as part of the kit-

p.s. I really will post a photo soon- been busy working the kinks out

 

[AdamC]

finally got some photos of completed bike- nicknamed black &decker