diff --git a/libtransmission/peer-mgr.c b/libtransmission/peer-mgr.c
index 9e6d3d2ae..ffff492be 100644
--- a/libtransmission/peer-mgr.c
+++ b/libtransmission/peer-mgr.c
@@ -558,12 +558,19 @@ broadcastGotBlock( Torrent * t, uint32_t index, uint32_t offset, uint32_t length
 
 static int reconnectPulse( void * vtorrent );
 
+static void
+restartReconnectTimer( Torrent * t )
+{
+    tr_timerFree( &t->reconnectTimer );
+    if( t->isRunning )
+        t->reconnectTimer = tr_timerNew( t->manager->handle, reconnectPulse, t, RECONNECT_PERIOD_MSEC );
+}
+
 static void
 reconnectNow( Torrent * t )
 {
     reconnectPulse( t );
-    tr_timerFree( &t->reconnectTimer );
-    t->reconnectTimer = tr_timerNew( t->manager->handle, reconnectPulse, t, RECONNECT_PERIOD_MSEC );
+    restartReconnectTimer( t );
 }
 
 static int
@@ -589,12 +596,19 @@ reconnectSoon( Torrent * t )
 
 static int rechokePulse( void * vtorrent );
 
+static void
+restartChokeTimer( Torrent * t )
+{
+    tr_timerFree( &t->rechokeTimer );
+    if( t->isRunning )
+        t->rechokeTimer = tr_timerNew( t->manager->handle, rechokePulse, t, RECHOKE_PERIOD_MSEC );
+}
+
 static void
 rechokeNow( Torrent * t )
 {
     rechokePulse( t );
-    tr_timerFree( &t->rechokeTimer );
-    t->rechokeTimer = tr_timerNew( t->manager->handle, rechokePulse, t, RECHOKE_PERIOD_MSEC );
+    restartChokeTimer( t );
 }
 
 static int
@@ -876,6 +890,7 @@ tr_peerMgrStartTorrent( tr_peerMgr     * manager,
 {
     Torrent * t = getExistingTorrent( manager, torrentHash );
     t->isRunning = 1;
+    restartChokeTimer( t );
     reconnectNow( t );
 }
 
@@ -885,7 +900,9 @@ tr_peerMgrStopTorrent( tr_peerMgr     * manager,
 {
     Torrent * t = getExistingTorrent( manager, torrentHash );
     t->isRunning = 0;
-    reconnectNow( t );
+    tr_timerFree( &t->rechokeTimer );
+    tr_timerFree( &t->reconnectTimer );
+    reconnectPulse( t );
 }
 
 void
@@ -902,8 +919,8 @@ tr_peerMgrAddTorrent( tr_peerMgr * manager,
     t->tor = tor;
     t->peers = tr_ptrArrayNew( );
     t->requested = tr_bitfieldNew( tor->blockCount );
-    t->rechokeTimer = tr_timerNew( manager->handle, rechokePulse, t, RECHOKE_PERIOD_MSEC );
-    t->reconnectTimer = tr_timerNew( manager->handle, reconnectPulse, t, RECONNECT_PERIOD_MSEC );
+    restartChokeTimer( t );
+    restartReconnectTimer( t );
 
     memcpy( t->hash, tor->info.hash, SHA_DIGEST_LENGTH );
     tr_ptrArrayInsertSorted( manager->torrents, t, torrentCompare );
diff --git a/libtransmission/peer-msgs.c b/libtransmission/peer-msgs.c
index 3b90a2e99..554226a2f 100644
--- a/libtransmission/peer-msgs.c
+++ b/libtransmission/peer-msgs.c
@@ -44,26 +44,30 @@
 
 enum
 {
-    BT_CHOKE           = 0,
-    BT_UNCHOKE         = 1,
-    BT_INTERESTED      = 2,
-    BT_NOT_INTERESTED  = 3,
-    BT_HAVE            = 4,
-    BT_BITFIELD        = 5,
-    BT_REQUEST         = 6,
-    BT_PIECE           = 7,
-    BT_CANCEL          = 8,
-    BT_PORT            = 9,
-    BT_SUGGEST         = 13,
-    BT_HAVE_ALL        = 14,
-    BT_HAVE_NONE       = 15,
-    BT_REJECT          = 16,
-    BT_ALLOWED_FAST    = 17,
-    BT_LTEP            = 20,
+    BT_CHOKE                  = 0,
+    BT_UNCHOKE                = 1,
+    BT_INTERESTED             = 2,
+    BT_NOT_INTERESTED         = 3,
+    BT_HAVE                   = 4,
+    BT_BITFIELD               = 5,
+    BT_REQUEST                = 6,
+    BT_PIECE                  = 7,
+    BT_CANCEL                 = 8,
+    BT_PORT                   = 9,
+    BT_SUGGEST                = 13,
+    BT_HAVE_ALL               = 14,
+    BT_HAVE_NONE              = 15,
+    BT_REJECT                 = 16,
+    BT_ALLOWED_FAST           = 17,
+    BT_LTEP                   = 20,
 
-    LTEP_HANDSHAKE     = 0,
+    LTEP_HANDSHAKE            = 0,
 
-    OUR_LTEP_PEX       = 1
+    OUR_LTEP_PEX              = 1,
+
+    /* disregard requests that want more than this many bytes.
+       it's common practice in for BT clients to use a 16K threshold */
+    MAX_REQUEST_BYTE_COUNT    = (16 * 1024)
 };
 
 enum
@@ -611,9 +615,16 @@ requestIsValid( const tr_peermsgs * msgs, struct peer_request * req )
 {
     const tr_torrent * tor = msgs->torrent;
     assert( req != NULL );
-    assert( req->index < (uint32_t)tor->info.pieceCount );
-    assert( (int)req->offset < tr_torPieceCountBytes( tor, (int)req->index ) );
-    assert( tr_pieceOffset( tor, req->index, req->offset, req->length ) <= tor->info.totalSize );
+
+    if( req->index >= (uint32_t) tor->info.pieceCount )
+        return FALSE;
+    if ( (int)req->offset >= tr_torPieceCountBytes( tor, (int)req->index ) )
+        return FALSE;
+    if( req->length > MAX_REQUEST_BYTE_COUNT )
+        return FALSE;
+    if( tr_pieceOffset( tor, req->index, req->offset, req->length ) > tor->info.totalSize )
+        return FALSE;
+
     return TRUE;
 }