[TowerTalk] 1/4 wave sloper impact on Ultrabeam/balun?

[m.jonink at wxs.nl]

Hi All,
New to the list.
My name is Martin, PA4WM
On 80m I have been using a 1/4 wave sloper on and off for the last 16 years.
Attached at 50ft on a crank up tower.
A Force 12 C3s was used for years, and acted as top loading for the sloper system. 
Worked well.
The C3 is replaced by a 2 elements Ultrabeam (fluid motion) yagi.
Nice to see the slopers resonant frequentie change, when switching the beam to different frequencies.
But that raised a question and concern as well.....
The Ultrabeam is fed with a 2:1 Balun. (This transforms the beam's 25 ohm odd impedance close to 50 ohm)
This balun operates in a low impedance area, where voltages are low.
The ultrabeam and sloper are connected with their coax outer shields at the bottom of the tower, where switchng is done with a remote antenne switch.
When operating the sloper, currents will flow up to the ultrabeam.
The internal balun will see currents and voltages that are different from the normal 50 ohm.
My biggest concern and question:
Could this damage the balun?
I searched for threads, and found 1/4 wave slopers and Steppir beams working together, but didn't find the balun issue mentioned.
Any thoughts?
73, Martin, PA4WM