Dual boot Sierra and Yosemite

[subdub]

Hi there !

My current setup runs the latest Sierra with Clover perflectly fine.
I needed a Yosemite (10.10.5) system as well so I did the following:

1. Disconnected the drive where Sierra is installed (to be safe)
2. Created an USB boot disk with Unibeast 6.2.0 + Yosemite 10.10.5 + Multibeast 7.5.0
3. Installed Yosemite, then ran MultiBeast with the "Easy Setup" feature and disabled the Chimera bootloader install
4. Rebooted, connected back the Sierra SSD, which runs the latest Clover version

At this point, I can see both of my systems, but Yosemite won't boot.
In verbose mode, the last log message is :

**** [IOBluetoothHCIController][SearchForTransportEventTimeOutHandler] -- Missing Bluetooth Controller Transport!

Nothings happen after this. Checked everything in my BIOS, tried different flag, but it won't boot.
However, if I boot from the USB stick, it boots fine.

I am wondering if what I am trying to do is possible ? Or does the latest Clover is specificly made to boot Sierra ?
In the meantime it's fine to boot via the USB stick but eventually I'd like to be able to just use the latest Clover version to boot both systems.

Any help appreciated !
Thank you !

My system specs:
- Gigabyte Z87 UD5H
- Intel i7 4770K
- GTX 780
- 32GB RAM
- No wifi card installed
- Audio disabled
- Intel Integrated Graphic disabled

 

[BreBo]

@subdub, please update your profile (personal details) with your build (Motherboard, CPU and Graphics Card).

Profiles need to contain at least your primary system to assist others with helping you.

 

[subdub]

@subdub, please update your profile (personal details) with your build (Motherboard, CPU and Graphics Card).

Done! Sorry about that

 

[BreBo]

Nothings happen after this. Checked everything in my BIOS, tried different flag, but it won't boot.
However, if I boot from the USB stick, it boots fine.

Perhaps copy the EFI folder on your USB drive to your SSD/HD?

Copy the EFI folder of your usb installer drive to the desktop, now mount the EFI partition of your hard drive, find and delete the EFI folder that is currently on the hard drive and replace it with the you copied from the usb drive.