[Jac Mac]

Whenever I get the chance I fit an electric solenoid to use for a faster running idle speed up around 900/1000 rpm depending on the cam specs etc. In this way there is less chance of stalling the motor under braking/spin out conditions & when you kill the ignition the throttle goes back to a 'true' idle setting to reduce the chance of run on etc on shutdown. Might be all you need to 'fix' your problem. Try it, set your idle speed @ 900/1000 temporarily & do the brake test, if it fix's it you know what to do.