client.go  |  4 ++--
 torrent.go | 10 ++++++++++

diff --git a/client.go b/client.go
index 6d8d7fbb6c7461b506e5fb920f52fa6fa384bcd9..5e4b5d848c5b5cecf2c626372039f81d7e6dc43b 100644
--- a/client.go
+++ b/client.go
@@ -2219,7 +2219,7 @@ 	if !cl.waitWantPeers(t) {
 		return
 	}
 	cl.mu.RLock()
-	req.Left = uint64(t.bytesLeft())
+	req.Left = t.bytesLeftAnnounce()
 	trackers := t.Trackers
 	cl.mu.RUnlock()
 	if cl.announceTorrentTrackersFastStart(&req, trackers, t) {
@@ -2228,7 +2228,7 @@ 	}
 newAnnounce:
 	for cl.waitWantPeers(t) {
 		cl.mu.RLock()
-		req.Left = uint64(t.bytesLeft())
+		req.Left = t.bytesLeftAnnounce()
 		trackers = t.Trackers
 		cl.mu.RUnlock()
 		numTrackersTried := 0
diff --git a/torrent.go b/torrent.go
index 00d5ac07aeb3d98e378a92a07b86d486a2447db4..6453c50804994a4eeae997808edf420ed77f2118 100644
--- a/torrent.go
+++ b/torrent.go
@@ -6,6 +6,7 @@ 	"expvar"
 	"fmt"
 	"io"
 	"log"
+	"math"
 	"math/rand"
 	"net"
 	"sort"
@@ -517,6 +518,15 @@ 	for i := 0; i < t.numPieces(); i++ {
 		left += int64(t.pieceNumPendingBytes(i))
 	}
 	return
+}
+
+// Bytes left to give in tracker announces.
+func (t *torrent) bytesLeftAnnounce() uint64 {
+	if t.haveInfo() {
+		return uint64(t.bytesLeft())
+	} else {
+		return math.MaxUint64
+	}
 }
 
 func (t *torrent) piecePartiallyDownloaded(piece int) bool {