Root Lenovo K3-note K50a40:
First ensure the battery of your phone is above 75%, so then it will never get
switched OFF during the middle of the process.
First of all i figured out problem with flashing twrp recovery and installing superSu app so it is highly Recommended you to download proper version from given link
Step 1=> Next extract the Recovery zip file and Spflash tool
See the image for difference between spflashtool
wrong version of spflashtool
Right one will show like this
so for success fully Flash recovery and root it is Highly Recommended to download the right version from given link
Step 3=> Click on "Scatter-loading" it will show dialog box and select "MT6752_Android_scatter.txt"from extracted recovery folder.
Step 4=> Now goto option -> downloaded and tick on "DA DL Checksum " and tick all as shown
Step 5=> Now select Download-only and click on download button.
Step 6=> switch off your phone and connect it to pc via usb cable.
Once process is Completed you will See Green check box appeard in sp flash tool and its done
disconnect your mobile and Press and hold VOL UP + VOL DOWN and push power on butten you will see cwm recovery.
Thank you and any problem with Regarding Lenovo K3 Note must welcome.