Upgrade Cordless Grass Trimmer | Black and Decker TYPE JP01

I bought this from a Japanese used store for $10. It works normally, but it is very weak, I use it to cut only young grass. I feel it is almost useless, but its resources are usable. I decide to made it a little better by replacing the old motor with a newer one. The result is acceptable, it is stronger than before.
Some information you may want to know
Old Grass Trimmer
Rotation speed 7400/min
No load power is about 50W
550 DC motor 18V
New Grass Trimmer
Rotation speed 8500/min
No load power is about 90W
755 DC motor 18V
I hope you find this video useful and enjoy it!
Furthermore, I am happy to receive feedback, suggestions to improve myself.
!!! I'm sorry for the mistake if I did in this video !!!
Thank you very much for choosing to watch my video!
Have a nice day
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