Having trouble setting this up with the doubler option.
Anyone have any success?
I'm using an older canti-style XT brake $ shifter combo with XT V-Brakes.
Feels mushy with the noodle so I bought a travel agent.
I'm using regular brake cable and it seems to bind when I thread it through the small hole in the pulley.

A I missing something here?
Should I be using the narrower guage shifter cable for my rear brake?

Hopefully someone out there has used one.
QBP's website is useless.

I have just fitted some to my bike! I also noticed that the hole is a bit small.
Have you tried twisting the cable as you thread it through?

Tried that.
Also tried a bit lube as well.
I did take the pulley off and I did get the cable through.
When I put it back together it hardly moved when I pulled the brake lever.

I fitted mine round the bigger part of the wheel and didn't bother with the lower part in the end. I have also used a similar product by Acor "pizza cutter" and that only has one pulley wheel for the same job and that works fine!
Try fitting it the easy way and see what happens.It worked for me!

Do you have the hi-lo bolts on top of your brake lever?
If so fit the travel agent the normal way and adjust the bolts on your brake lever and see what feels best.