diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index dc013757e9..97af01c788 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -141,12 +141,14 @@ static void rlimit_tune_steps(struct Curl_rlimit *r,
         r->step_us = CURL_US_PER_SEC + ((timediff_t)mstep_inc * 1000);
         r->rate_per_step += rate_inc;
         r->tokens = r->rate_per_step;
+        if(r->burst_per_step) {
+          curl_off_t burst_inc = ((r->burst_per_step * mstep_inc) / 1000);
+          if(burst_inc)
+            r->burst_per_step += burst_inc;
+        }
       }
     }
   }
-
-  if(r->burst_per_step)
-    r->burst_per_step = r->rate_per_step;
 }
 
 void Curl_rlimit_init(struct Curl_rlimit *r,
diff --git a/lib/setopt.c b/lib/setopt.c
index e2e30622f1..e56d69129e 100644
--- a/lib/setopt.c
+++ b/lib/setopt.c
@@ -2768,7 +2768,9 @@ static CURLcode setopt_offt(struct Curl_easy *data, CURLoption option,
     if(offt < 0)
       return CURLE_BAD_FUNCTION_ARGUMENT;
     s->max_send_speed = offt;
-    Curl_rlimit_init(&data->progress.ul.rlimit, offt, offt,
+    /* use minimal burst rate of 32k. some protocol batch IO */
+    Curl_rlimit_init(&data->progress.ul.rlimit, offt,
+                     CURLMAX(offt, (32 * 1024)),
                      Curl_pgrs_now(data));
     break;
   case CURLOPT_MAX_RECV_SPEED_LARGE:
@@ -2779,7 +2781,9 @@ static CURLcode setopt_offt(struct Curl_easy *data, CURLoption option,
     if(offt < 0)
       return CURLE_BAD_FUNCTION_ARGUMENT;
     s->max_recv_speed = offt;
-    Curl_rlimit_init(&data->progress.dl.rlimit, offt, offt,
+    /* use minimal burst rate of 32k. some protocol batch IO */
+    Curl_rlimit_init(&data->progress.dl.rlimit, offt,
+                     CURLMAX(offt, (32 * 1024)),
                      Curl_pgrs_now(data));
     break;
   case CURLOPT_RESUME_FROM_LARGE: