diff --git a/src/pow.cpp b/src/pow.cpp
index cddd67832ec..1b4d805dc9d 100644
--- a/src/pow.cpp
+++ b/src/pow.cpp
@@ -245,7 +245,8 @@ unsigned int CalculateNextWorkRequired(const CBlockIndex* pindexLast, int64_t nF
     bnNew.SetCompact(pindexLast->nBits);
     bnOld = bnNew;
     // Monacoin: intermediate uint256 can overflow by 1 bit
-    bool fShift = bnNew.bits() > 235;
+    const arith_uint256 bnPowLimit = UintToArith256(params.powLimit);
+    bool fShift = bnNew.bits() > bnPowLimit.bits() - 1;
     if (fShift)
         bnNew >>= 1;
     bnNew *= nActualTimespan;
@@ -253,7 +254,6 @@ unsigned int CalculateNextWorkRequired(const CBlockIndex* pindexLast, int64_t nF
     if (fShift)
         bnNew <<= 1;
 
-    const arith_uint256 bnPowLimit = UintToArith256(params.powLimit);
     if (bnNew > bnPowLimit)
         bnNew = bnPowLimit;