1,800W & 3,000W brushless motors with 20S to 24S - 18 ah LTOs and brush chain drives.

curtis

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I will be working on a custom build for my brushless motor. It is currently on a 20" BMX style bike and since I have no welding skills, I used wood. Recently I acquired a wire welder and want to weld a steel plate to replace the wood. However, need to be able to loosen the chain to change a flat tire and need a couple inches and a way to keep the chain tight. The controller is 1,500W and runs 36 to 48V. 38 amps. 48V * 38 amps = 1,824W total. Gearing will be around 35 to 36 mph.

I ran the bike before with a 30 amp 1,200W lion battery which was 13S - 7P. Top speed was 28 mph. I also ran it with 16S - LIFEPO4 - 5P but the cells were not top quality and was considerable voltage sag and 25 mph was the top speed. I am not sure if I will be using the 20" frame as mounting 20S - LTO will be a challenge. It needs to be low center of gravity. Also, I am only 5 feet 8 inches so do not want it to be over 24" bike.

It is a summer project. I also have a 3,000W brushless motor that needs to be built. I have a 70-amp 60V controller for that. I have two working 8S - LTO packs both with active cell balancers and 8 - LTOs left over. I bought two 4S active balancers for 50V or 60V. The problem is the weight and mounting options.

I will keep posting when I start making progress.

Thanks.

Curtis out.
 

curtis

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Yea.

Looking at swapping motors. I removed the 1,800W brushless motor from the 20" BMX. I still need a piece of #40 roller chain. I have a 26" Currie eZip Trailz. My first e bike purchased at Wall-Mart back in 2013. I have had about half a dozen motors on it and currently has a 36V - 1,000W unite brush chain drive in the rear and 350W Bafang up front. The problem with it is someone lied when they rated the motor at 3,000 rpm @ 36V.

I do not see it. I had two 48V - 3,000 rpm 1,000W motors in the past which ran circles around this 36V lie. Much greater acceleration and about 5 or 6 mph faster top speed. I am not sure, but gearing is supposed to be for 28 mph. IT might do it but takes forever. It acts over-geared. I had a 40 amp controller and did not hit more than 28 mph.

The 1,800W brushless motor is 3,000 rpms at 48V. - 1,500W and geared for 35 mph @ 40V - LTO - 2,500 rpm That is with a 26" wheel.

The 20" bike will get the 36V - brush - 1,000W - 3,000 rpm ????? in the rear with a 89T wheel and 11T motor - #25 chain. 20" wheel is only 22 mph. If it goes faster, I know it is over geared.

I won't be finished there though. I am looking at an 800W - 36V brush Unite motor up front. It is 2,750 rpm at 36V. With an 80T #25 sprocket I will get 22 mph as well.

The interesting part however is they can handle 50V - LTO which will net 30 mph and a whopping 1,388 + 1111 = 2,499 watts. I plan on full brake upgrades and using it for steady 25 to 27 mph cruising. With two motors and controllers sharing the load and heat dissipation it should hold up and be reliable plus long lasting.

As for the others I will be removing the front Bafang from both the Currie and 26" Dual suspension. The 26" dual suspension with rhe 48V 1,000W direct drive will see 60V - LTO. 1,250W and 32 mph. I have a third Bafang motor so would like a trike. I want two front wheels though. Thinking about bolting two forks to one. Then I can run two Bafangs up front and one in the rear. All off one throttle.

I ran dual Bafangs today for almost 15 miles with my 16S - LTOs. My vintage 90s Diamondback Outlook. top speed is limited to 20 mph but the Bafang motors seem to be reliable work horses.

I will post when more progress is made.


Thanks.

Curtis out
 

curtis

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Well.

It is about thumb throttles. I use a single thumb throttle for dual 350W Bafangs.

I had two motors on the same 20" BMX about 5 years ago. A 500W - 2,500 rpm 24V and the 800W - 36V - 2,750 rpm 36V both brushed. At 36V it was 20+ mph. At 48V 30+. two throttles. The front 2,750W motor was with a 60T #410 chain. The 24V - 2,500W motor sported #25 chain and 80T wheel sprocket. Basically, was same thing I am building but will be experimenting with single vs dual throttles.

I took both motors off for the 1,800W brushless motor. That is why the 1,800W brushless motor on the Currie is a huge upgrade from the wimpy over geared motor.

But that s**tty motor working with another almost equal and over volted will equal an animal capable of 30 mph quickly. > 2 kilowatts. Just use the throttle to control it. Should work with single throttle. Take it easy. lol. 48V is like turbo mode. Do 36V first 20+ mph gearing then switch to 48 or 50V. lol

The sprockets, chains and other parts I already have. Except for a left thread nut for motor sprocket and a piece of #40 roller chain.

Thanks for posting. I will do pics. and video when I start building.

Not sure what building first. I have three running but want to upgrade two. Then start working on the others.

Thanks.

Curtis out.
 
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