Follow these steps to root your Yu Yureka. Please be warned that, rooting your phone voids your warranty.
Make sure your battery is at least at 80% charge.Create a backup to fall back on if anything goes wrong.Follow the procedure carefully, else your phone may get bricked.
Steps to Unlock Bootloader and Install CWM recovery
1. Download ADB Fastboot from this link https://docs.google.com/uc?authuser=0&id=0B_M-QdcfhN5bT2pqN2JXSVJtVTg&export=download
2. Extract these files to a new folder in the phone and name the folder as ADB.
3. Switch off your Yu and connect to PC via USB. Make sure USB debugging is enabled on your phone.
4. When the LED goes RED, keep and hold Volume Up button. Fastboot screen will come up on your phone.
5. Now locate the newly created ADB folder and find "RUN ME" file. Double click to open command prompt.
6. Type adb reboot bootloader
7. then enter fastboot -i 0x1ebf oem unlock. This will unlock your bootloader. Please note that this will erase all data from your phone.
8. Download CWM recovery from this link https://s.basketbuild.com/devs/vishal_android_freak/yu/yureka and save it to your ADB folder.
9. Reboot your device again as in step 6.
10. Now type fastboot -i 0x1ebf flash recovery recovery-yu.img. This will install CWM recovery.
11. Now reboot your phone by entering fastboot reboot
Steps to Rooting
So you have unlocked the bootloader and installed CWM recovery. Next step is to root your device.
1. Download SuperSU from the link http://download.chainfire.eu/641/SuperSU/UPDATE-SuperSU-v2.40.zip
2. Save this file to the root of your SD card.
3. Switch off your phone, and boot in CWM recovery mode by Pressing Volume UP,Volume Down and Power button simultaneously.
4. Select Install zip from SD card option and choose SuperSu file you just downloaded.
5. Wait for the setup to finish and once done. reboot your phone.