Walker has been with Brewin Dolphin since 2004, as one of the founding directors of the Exeter office.
Pike who has led the Exeter office since it was established, said: "Tim and I have worked closely together to build the office since we opened it eight years ago and we are confident that this will be a seamless transition for the branch and our clients."
Prior to joining Brewin Dolphin, Walker was at Barclays Wealth-owned discretionary investment manager Gerrard, in Exeter.
Before that he worked for Prudential-Bache on Wall Street.
Walker said: "We have an excellent team in Exeter who have built one of the fastest growing offices in the group. We are seeing increasing demand for our services in these uncertain times and I very much look forward to my new role ensuring our continued growth."
Brewin Dolphin as a whole manages £24bn for over 130,000 clients, £15.6bn is on a discretionary basis.