Slow acceleration for 72v 2000w ebike.

Bike is actually pretty awesome for the young folks, and with a new rear shock it would be able to commute a full size adult

It is really fast and silent as ever on flat ground and when my daughter is wide open throttle I cannot catch her on the 18s Kuberg which is pretty fast

I rebuilt the entire bike from the ground up and it has all new components on it, but I did re-use the controller, LCD and battery

also put on a Voloci seat looks a tad odd but it is way more comfortable and it actually raised the ride height a tad bit. The dirt bike look does not help when we ride on the street a lot of the time anyway
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Finally got around to posting this video, the footage was held hostage on my work PC until i had IT allow me to transfer it back to a USB drive...


 
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Super Post brother!
 
Bought a new GoPro 7 hero silver and got to test the video quality difference between it and my old Swag 1080 action cam...It is night and day difference...The sound quality is so much better on the GoPro also making it a winner in both categories(go figure)

And every time you buy a GoPro new they are set to 4:3 ratio for vertical action and I forgot to change it to widescreen prior to testing it out, either way I edited down the two videos from 30 minutes down to 14 minutes and sped up alot of the road commute to the trail we were trying to get to...Enjoy the ride with us!

 
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So is "2kw" a 35H motor? 35mm magnet height/stator width or maybe its an outright lie to get the higher power watt sales.

45H is lazied # @ 3kw mxus/qs and 50H is lazied out # @ 3/4/5k from the same suspects but at least they list what height/width (H) it is.
 
markz said:
So is "2kw" a 35H motor? 35mm magnet height/stator width or maybe its an outright lie to get the higher power watt sales.

45H is lazied # @ 3kw mxus/qs and 50H is lazied out # @ 3/4/5k from the same suspects but at least they list what height/width (H) it is.
Click to expand...

This is the only information I have off the motor, I ordered an exact replacement matching the serial numbers so it would lace in and fit the same since I reused the spokes and rim/tire popped the tube and replaced it

This motor is slightly larger than a 48v 1000w kit which are usually 28mm so 35mm may be accurate but its no power house like a QS or MXUS
 

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So my daughter continues to beat the crap out of this bike and it now has around 300 miles on it. She finally wore out and broke both crappy plastic pedals that come in the bike. I went to put new ones on only to find out that they are both Right sided thread pedals... so you need to buy two sets to replace both pedals...hahaha so funny you got me guys!

She also dropped it in the field and broke one of the inverted fork plastic slide protectors off the front fork too! Looks a tad bit odd with only 1 on there now I may remove the other one.
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Why keep pedals there? Wouldn't footpegs work just as well and take more beating?
 
99t4 said:
Why keep pedals there? Wouldn't footpegs work just as well and take more beating?
Click to expand...

That's true, they would work if they were threaded like a bicycle pedal, but I just used two pedals I had kicking around the house. She did mention that she likes the large wide metal platform pedal better than the plastic since its more comfortable on her feet
 
So the rear brake pads on the Ebay electric dirt bike have literally disintegrated and they no longer exist so the rear caliper is flopping around on the disc. She has roughly 500miles on the bike. I am trying to look on Ebay and Amazon for the brake pads but I am trying to find them by how the caliper looks so they are hard to track down

hopefully I can find them soon and order a set for her, she tends to use her rear brake more than her fronts on the pavement, so this will be a good lesson for her to use the front more at times
 
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Instead of trying to identify the calipers it's better to find replacement pads by comparing and matching their profile as shown on a compatibility chart. Here are two examples, you can easily find more online:

http://www.koolstop.com/english/pdf/08_20_15_DISC_PSTR_PROOF_C.pdf

https://www.jbi.bike/site/disc_pads.php

Edited to update links to better charts.
 
Thanks for the chart links! But the pads are completely gone/dust in the wind/missing, there is nothing left for reference at all. It actually wore out the round piston that pushes the pads to the rotor, it was rubbing against the disc at an angle and its ruined too, so the entire caliper is now faulty

Forgot to take pics when I tore it off yesterday

I will be trying to buy an entire new one, and then I can take a picture of the pads and stay on top of it...
 
Yeah, it's needing more than replacement pads, lol :lol: .

May I suggest Shimano or Tektro, pads easy to change out, widely available, reasonable price, work well.
 

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skeetab5780 said:
Do you think this one will work? Im about to order it and try
Click to expand...
Just guessing from the photos but looks like the mounting ears are different?
 
99t4 said:
skeetab5780 said:
Do you think this one will work? Im about to order it and try
Click to expand...
Just guessing from the photos but looks like the mounting ears are different?
Click to expand...

I bought it anyway, its the closest thing I could find should have it in hand soon enough. Worst case I may need to create a small metal bracket or something
 
I am back to square 1 the caliper I ordered was huge! you were right its not going to fit
 
My daughter finally fried the stock controller on the bike. She rides the thing every single day atleast one full charge if not more. She told me she was going up a grass hill and it made a noise and stopped working...First thing I do to trouble shoot the bike was lift the rear wheel and try to spin it... It did not spin. I knew right then and there the controller fried since its in the battery enclosure and get hot as sin it was only a matter of time.

I opened the battery side cover and quickly disconnected the three motor phase wires from the controller and again lifted the rear wheel to see if it spins...and luckily it spun freely! Phew

I just happened to have a 72v 2000w Ebay controller sitting around that I used to test the Voloci death bike motors with, so I slapped it in the bike( the SW900 display does not work now I had to bypass it) and wired it to the existing key switch from the Apollo 250cc dirt bike and gave it a quick test and the motor was back working!

Unfortunately I completely screw the side cover back on, then go to test the bike...Lol it is going in reverse...Doh

I took the 6x side cover bolts off one more time! and connect the white jumpers on the controller to switch direction and the bike tries to take off down the yard, I grab the back end of the bike real quick while the motor spins away the correct direction in full speed and have my daughter disconnect the jumper since my hands were occupied! Now its back in action

The controller was actually a tad bit longer and barely fit in the battery case above the battery, I had to cram it in place.

I am curious how many watts its actually putting out because she thinks it is a tad faster, but I think its only a 2000w controller not a 3000w. But who knows it could be 72v 40a like the old one

One thing she noticed that I did not was the noise, the old controller was sine wave and the motor was silent, The "new" one I just put in is a regular trapezoidal square wave and the motor now makes noise...which I kind of like just used to it
 
Looks like I was wrong about it being the controller it ended up being a short in the motor phase wires where it entered the battery enclosure under that battery
 
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