diff --git a/chain/blocksync/blocksync.go b/chain/blocksync/blocksync.go
index b810c7783..ba8c64ebf 100644
--- a/chain/blocksync/blocksync.go
+++ b/chain/blocksync/blocksync.go
@@ -8,12 +8,11 @@ import (
 	"go.opencensus.io/trace"
 	"golang.org/x/xerrors"
 
-	"github.com/filecoin-project/go-cbor-util"
+	cborutil "github.com/filecoin-project/go-cbor-util"
 	"github.com/filecoin-project/lotus/chain/store"
 	"github.com/filecoin-project/lotus/chain/types"
 
 	"github.com/ipfs/go-cid"
-	cbor "github.com/ipfs/go-ipld-cbor"
 	logging "github.com/ipfs/go-log/v2"
 	inet "github.com/libp2p/go-libp2p-core/network"
 	"github.com/libp2p/go-libp2p-core/peer"
@@ -25,12 +24,6 @@ type NewStreamFunc func(context.Context, peer.ID, ...protocol.ID) (inet.Stream,
 
 const BlockSyncProtocolID = "/fil/sync/blk/0.0.1"
 
-func init() {
-	cbor.RegisterCborType(BlockSyncRequest{})
-	cbor.RegisterCborType(BlockSyncResponse{})
-	cbor.RegisterCborType(BSTipSet{})
-}
-
 type BlockSyncService struct {
 	cs *store.ChainStore
 }
@@ -55,8 +48,8 @@ func ParseBSOptions(optfield uint64) *BSOptions {
 }
 
 const (
-	BSOptBlocks   = 1 << 0
-	BSOptMessages = 1 << 1
+	BSOptBlocks = 1 << iota
+	BSOptMessages
 )
 
 type BlockSyncResponse struct {
diff --git a/chain/blocksync/blocksync_client.go b/chain/blocksync/blocksync_client.go
index f3d681e46..885ed2de7 100644
--- a/chain/blocksync/blocksync_client.go
+++ b/chain/blocksync/blocksync_client.go
@@ -18,9 +18,10 @@ import (
 	"go.opencensus.io/trace"
 	"golang.org/x/xerrors"
 
-	"github.com/filecoin-project/go-cbor-util"
+	cborutil "github.com/filecoin-project/go-cbor-util"
 	"github.com/filecoin-project/lotus/chain/store"
 	"github.com/filecoin-project/lotus/chain/types"
+	incrt "github.com/filecoin-project/lotus/lib/increadtimeout"
 	"github.com/filecoin-project/lotus/node/modules/dtypes"
 	"github.com/filecoin-project/lotus/peermgr"
 )
@@ -241,16 +242,19 @@ func (bs *BlockSync) sendRequestToPeer(ctx context.Context, p peer.ID, req *Bloc
 		bs.RemovePeer(p)
 		return nil, xerrors.Errorf("failed to open stream to peer: %w", err)
 	}
-	s.SetDeadline(time.Now().Add(10 * time.Second))
-	defer s.SetDeadline(time.Time{})
+	s.SetWriteDeadline(time.Now().Add(5 * time.Second))
 
 	if err := cborutil.WriteCborRPC(s, req); err != nil {
+		s.SetWriteDeadline(time.Time{})
 		bs.syncPeers.logFailure(p, time.Since(start))
 		return nil, err
 	}
+	s.SetWriteDeadline(time.Time{})
 
 	var res BlockSyncResponse
-	if err := cborutil.ReadCborRPC(bufio.NewReader(s), &res); err != nil {
+	r := incrt.New(s, 50<<10, 5*time.Second)
+
+	if err := cborutil.ReadCborRPC(bufio.NewReader(r), &res); err != nil {
 		bs.syncPeers.logFailure(p, time.Since(start))
 		return nil, err
 	}
diff --git a/go.mod b/go.mod
index 914691b7f..0660c07b5 100644
--- a/go.mod
+++ b/go.mod
@@ -87,6 +87,7 @@ require (
 	github.com/stretchr/testify v1.4.0
 	github.com/whyrusleeping/bencher v0.0.0-20190829221104-bb6607aa8bba
 	github.com/whyrusleeping/cbor-gen v0.0.0-20200121162646-b63bacf5eaf8
+	github.com/whyrusleeping/go-logging v0.0.0-20170515211332-0457bb6b88fc
 	github.com/whyrusleeping/multiaddr-filter v0.0.0-20160516205228-e903e4adabd7
 	github.com/whyrusleeping/pubsub v0.0.0-20131020042734-02de8aa2db3d
 	go.opencensus.io v0.22.2
diff --git a/go.sum b/go.sum
index 47f2659a5..25110e48c 100644
--- a/go.sum
+++ b/go.sum
@@ -717,6 +717,7 @@ github.com/whyrusleeping/chunker v0.0.0-20181014151217-fe64bd25879f h1:jQa4QT2UP
 github.com/whyrusleeping/chunker v0.0.0-20181014151217-fe64bd25879f/go.mod h1:p9UJB6dDgdPgMJZs7UjUOdulKyRr9fqkS+6JKAInPy8=
 github.com/whyrusleeping/go-keyspace v0.0.0-20160322163242-5b898ac5add1 h1:EKhdznlJHPMoKr0XTrX+IlJs1LH3lyx2nfr1dOlZ79k=
 github.com/whyrusleeping/go-keyspace v0.0.0-20160322163242-5b898ac5add1/go.mod h1:8UvriyWtv5Q5EOgjHaSseUEdkQfvwFv1I/In/O2M9gc=
+github.com/whyrusleeping/go-logging v0.0.0-20170515211332-0457bb6b88fc h1:9lDbC6Rz4bwmou+oE6Dt4Cb2BGMur5eR/GYptkKUVHo=
 github.com/whyrusleeping/go-logging v0.0.0-20170515211332-0457bb6b88fc/go.mod h1:bopw91TMyo8J3tvftk8xmU2kPmlrt4nScJQZU2hE5EM=
 github.com/whyrusleeping/go-notifier v0.0.0-20170827234753-097c5d47330f/go.mod h1:cZNvX9cFybI01GriPRMXDtczuvUhgbcYr9iCGaNlRv8=
 github.com/whyrusleeping/go-smux-multiplex v3.0.16+incompatible/go.mod h1:34LEDbeKFZInPUrAG+bjuJmUXONGdEFW7XL0SpTY1y4=
diff --git a/lib/increadtimeout/incrt.go b/lib/increadtimeout/incrt.go
new file mode 100644
index 000000000..bb209ee8f
--- /dev/null
+++ b/lib/increadtimeout/incrt.go
@@ -0,0 +1,63 @@
+package incrt
+
+import (
+	"io"
+	"time"
+
+	logging "github.com/ipfs/go-log/v2"
+)
+
+var log = logging.Logger("incrt")
+
+var now = time.Now
+
+type ReaderDeadline interface {
+	Read([]byte) (int, error)
+	SetReadDeadline(time.Time) error
+}
+
+type incrt struct {
+	rd ReaderDeadline
+
+	waitPerByte time.Duration
+	wait        time.Duration
+	maxWait     time.Duration
+}
+
+// New creates an Incremental Reader Timeout, with minimum sustained speed of
+// minSpeed bytes per second and with maximum wait of maxWait
+func New(rd ReaderDeadline, minSpeed int64, maxWait time.Duration) io.Reader {
+	return &incrt{
+		rd:          rd,
+		waitPerByte: time.Second / time.Duration(minSpeed),
+		wait:        maxWait,
+		maxWait:     maxWait,
+	}
+}
+
+func (crt *incrt) Read(buf []byte) (n int, err error) {
+	start := now()
+	err = crt.rd.SetReadDeadline(start.Add(crt.wait))
+	if err != nil {
+		return 0, err
+	}
+
+	defer func() {
+		crt.rd.SetReadDeadline(time.Time{})
+		if err == nil {
+			dur := now().Sub(start)
+			crt.wait -= dur
+			crt.wait += time.Duration(n) * crt.waitPerByte
+			if crt.wait < 0 {
+				crt.wait = 0
+			}
+			if crt.wait > crt.maxWait {
+				crt.wait = crt.maxWait
+			}
+			log.Warnf("max wait: %s, dur: %s, n: %d", crt.wait.String(), dur.String(), n)
+		}
+	}()
+
+	n, err = crt.rd.Read(buf)
+	return n, err
+}