Servo/speedo questions

[tdi250]

Hello,

I'm getting back into 1/10th buggies after a long break and have been running my old brushed ESC and motors with an old quick servo until now.

However i have purchased a brushless ESC (LRP Sphere). I was going to use it with my brushed motors until i could afford to get some new brushless ones but i am concerned that my servo may not work with this speedo.

My old Tekin brushed speedo has a wire coming from it which connects to a single wire on the servo via a resistor, as well as the usual 3 wire lead to the receiver, obviously the LRP Sphere doesn't have one of these wires, does this mean that I now need to buy a new servo also? and if so what sort do i need as i'm still using my old 27Mgz radio gear (stop snigggering!!)

Any help would be great!!
Ta
Wes