diff --git a/vehicle/OVMS.V3/components/esp32can/src/esp32can.cpp b/vehicle/OVMS.V3/components/esp32can/src/esp32can.cpp
index b27101e08..a3b9afcb5 100644
--- a/vehicle/OVMS.V3/components/esp32can/src/esp32can.cpp
+++ b/vehicle/OVMS.V3/components/esp32can/src/esp32can.cpp
@@ -442,7 +442,7 @@ esp_err_t esp32can::InitController()
   /* Set sampling
    * 1 -> triple; the bus is sampled three times; recommended for low/medium speed buses     (class A and B) where filtering spikes on the bus line is beneficial
    * 0 -> single; the bus is sampled once; recommended for high speed buses (SAE class C)*/
-  MODULE_ESP32CAN->BTR1.B.SAM=0x1;
+  MODULE_ESP32CAN->BTR1.B.SAM = (MyESP32can->m_speed < CAN_SPEED_125KBPS) ? 1 : 0;
 
   // Enable all interrupts except arbitration loss (can be ignored):
   uint32_t ier = 0xff & ~__CAN_IRQ_ARB_LOST;
diff --git a/vehicle/OVMS.V3/components/mcp2515/src/mcp2515.cpp b/vehicle/OVMS.V3/components/mcp2515/src/mcp2515.cpp
index 126a62239..2600e6b3b 100644
--- a/vehicle/OVMS.V3/components/mcp2515/src/mcp2515.cpp
+++ b/vehicle/OVMS.V3/components/mcp2515/src/mcp2515.cpp
@@ -217,7 +217,13 @@ esp_err_t mcp2515::Start(CAN_mode_t mode, CAN_speed_t speed)
       cnf1=0x41; cnf2=0xf1; cnf3=0x85;
       break;
     case CAN_SPEED_500KBPS:
-      cnf1=0x00; cnf2=0xf0; cnf3=0x86;
+      // cnf1=0x00; cnf2=0xf0; cnf3=0x86; original code
+      // SAE/CiA recommendation
+      // PROP=5, PS1=8, PS2=2, SJW=2, Sample 1x @87.5%
+      cnf1=0x40; cnf2=0xbc; cnf3=0x81;
+      // Arduino MCP_CAN lib
+      // PROP=6, PS1=5, PS2=4, SJW=2, Sample 3x @75%
+      // cnf1=0x40; cnf2=0xe5; cnf3=0x83;
       break;
     case CAN_SPEED_1000KBPS:
       cnf1=0x00; cnf2=0xca; cnf3=0x81;