diff --git a/client.go b/client.go
index 3b5cac4..c25d24f 100644
--- a/client.go
+++ b/client.go
@@ -215,16 +215,6 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		}
 	}
 
-	readBufferSize := d.ReadBufferSize
-	if readBufferSize == 0 {
-		readBufferSize = 4096
-	}
-
-	writeBufferSize := d.WriteBufferSize
-	if writeBufferSize == 0 {
-		writeBufferSize = 4096
-	}
-
 	if len(d.Subprotocols) > 0 {
 		h := http.Header{}
 		for k, v := range requestHeader {
@@ -234,7 +224,7 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		requestHeader = h
 	}
 
-	conn, resp, err := NewClient(netConn, u, requestHeader, readBufferSize, writeBufferSize)
+	conn, resp, err := NewClient(netConn, u, requestHeader, d.ReadBufferSize, d.WriteBufferSize)
 	if err != nil {
 		return nil, resp, err
 	}
diff --git a/conn.go b/conn.go
index dc7d111..005b6d8 100644
--- a/conn.go
+++ b/conn.go
@@ -16,6 +16,20 @@ import (
 	"time"
 )
 
+const (
+	maxFrameHeaderSize         = 2 + 8 + 4 // Fixed header + length + mask
+	maxControlFramePayloadSize = 125
+	finalBit                   = 1 << 7
+	maskBit                    = 1 << 7
+	writeWait                  = time.Second
+
+	defaultReadBufferSize  = 4096
+	defaultWriteBufferSize = 4096
+
+	continuationFrame = 0
+	noFrame           = -1
+)
+
 // Close codes defined in RFC 6455, section 11.7.
 const (
 	CloseNormalClosure           = 1000
@@ -55,20 +69,13 @@ const (
 	PongMessage = 10
 )
 
-var (
-	continuationFrame = 0
-	noFrame           = -1
-)
+// ErrCloseSent is returned when the application writes a message to the
+// connection after sending a close message.
+var ErrCloseSent = errors.New("websocket: close sent")
 
-var (
-	// ErrCloseSent is returned when the application writes a message to the
-	// connection after sending a close message.
-	ErrCloseSent = errors.New("websocket: close sent")
-
-	// ErrReadLimit is returned when reading a message that is larger than the
-	// read limit set for the connection.
-	ErrReadLimit = errors.New("websocket: read limit exceeded")
-)
+// ErrReadLimit is returned when reading a message that is larger than the
+// read limit set for the connection.
+var ErrReadLimit = errors.New("websocket: read limit exceeded")
 
 // netError satisfies the net Error interface.
 type netError struct {
@@ -99,14 +106,6 @@ var (
 	errInvalidControlFrame = errors.New("websocket: invalid control frame")
 )
 
-const (
-	maxFrameHeaderSize         = 2 + 8 + 4 // Fixed header + length + mask
-	maxControlFramePayloadSize = 125
-	finalBit                   = 1 << 7
-	maskBit                    = 1 << 7
-	writeWait                  = time.Second
-)
-
 func hideTempErr(err error) error {
 	if e, ok := err.(net.Error); ok && e.Temporary() {
 		err = struct{ error }{err}
@@ -167,17 +166,24 @@ type Conn struct {
 	handlePing    func(string) error
 }
 
-func newConn(conn net.Conn, isServer bool, readBufSize, writeBufSize int) *Conn {
+func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int) *Conn {
 	mu := make(chan bool, 1)
 	mu <- true
 
+	if readBufferSize == 0 {
+		readBufferSize = defaultReadBufferSize
+	}
+	if writeBufferSize == 0 {
+		writeBufferSize = defaultWriteBufferSize
+	}
+
 	c := &Conn{
 		isServer:       isServer,
-		br:             bufio.NewReaderSize(conn, readBufSize),
+		br:             bufio.NewReaderSize(conn, readBufferSize),
 		conn:           conn,
 		mu:             mu,
 		readFinal:      true,
-		writeBuf:       make([]byte, writeBufSize+maxFrameHeaderSize),
+		writeBuf:       make([]byte, writeBufferSize+maxFrameHeaderSize),
 		writeFrameType: noFrame,
 		writePos:       maxFrameHeaderSize,
 	}
diff --git a/server.go b/server.go
index c24c410..349e5b9 100644
--- a/server.go
+++ b/server.go
@@ -21,11 +21,6 @@ type HandshakeError struct {
 
 func (e HandshakeError) Error() string { return e.message }
 
-const (
-	defaultReadBufferSize  = 4096
-	defaultWriteBufferSize = 4096
-)
-
 // Upgrader specifies parameters for upgrading an HTTP connection to a
 // WebSocket connection.
 type Upgrader struct {
@@ -147,15 +142,7 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 		return nil, errors.New("websocket: client sent data before handshake is complete")
 	}
 
-	readBufSize := u.ReadBufferSize
-	if readBufSize == 0 {
-		readBufSize = defaultReadBufferSize
-	}
-	writeBufSize := u.WriteBufferSize
-	if writeBufSize == 0 {
-		writeBufSize = defaultWriteBufferSize
-	}
-	c := newConn(netConn, true, readBufSize, writeBufSize)
+	c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize)
 	c.subprotocol = subprotocol
 
 	p := c.writeBuf[:0]