Max Speed changing

[OSCreator]

I am working on a program where if object A hits object B, object B's max speed will be subtracted by 5.
But when I go on object B's actions, I can't subtract from original max speed.

It should be-

if> Object A hits Object B
then> set Object B max speed to Object B [color:#FF0000]Max Speed[/color] -5

But I can't set a max speed to a max speed as it doesn't come up with the option of 'Max Speed'.
Any ideas/fixing updates?

[Game_Master]

Ok, I think that I have found a way that I have tested and it works:
+ Always
- Set "Object A" maximum speed to alterable value A

+ Start of frame
- Set "Object A" alterable value A to 50

+ Collision between "Object A" and "Object B"
- Subtract 5 from alterable value A of "Object A"

Key:
+: Condition
-: Action

Hope this helps!
EDIT:
Example File