diff --git a/src/main/drivers/bus_i2c_stm32f10x.c b/src/main/drivers/bus_i2c_stm32f10x.c
index 7daea6fa95..be298d3cf9 100644
--- a/src/main/drivers/bus_i2c_stm32f10x.c
+++ b/src/main/drivers/bus_i2c_stm32f10x.c
@@ -53,19 +53,23 @@ static void i2cUnstick(IO_t scl, IO_t sda);
 #ifndef I2C1_SDA
 #define I2C1_SDA PB9
 #endif
+
 #else
+
 #ifndef I2C1_SCL
 #define I2C1_SCL PB6
 #endif
 #ifndef I2C1_SDA
 #define I2C1_SDA PB7
 #endif
+#define IOCFG_I2C   IO_CONFIG(GPIO_Mode_AF_OD, GPIO_Speed_50MHz)
 
 #endif
 
 #ifndef I2C2_SCL
 #define I2C2_SCL PB10
 #endif
+
 #ifndef I2C2_SDA
 #define I2C2_SDA PB11
 #endif
@@ -398,8 +402,8 @@ void i2cInit(I2CDevice device)
     IOConfigGPIOAF(scl, IOCFG_I2C, GPIO_AF_I2C);
     IOConfigGPIOAF(sda, IOCFG_I2C, GPIO_AF_I2C);
 #else
-    IOConfigGPIO(scl, IOCFG_AF_OD);
-    IOConfigGPIO(sda, IOCFG_AF_OD);
+    IOConfigGPIO(scl, IOCFG_I2C);
+    IOConfigGPIO(sda, IOCFG_I2C);
 #endif
 
     I2C_DeInit(i2c->dev);
diff --git a/src/main/drivers/bus_i2c_stm32f30x.c b/src/main/drivers/bus_i2c_stm32f30x.c
index 88b267f111..d06eeece4c 100644
--- a/src/main/drivers/bus_i2c_stm32f30x.c
+++ b/src/main/drivers/bus_i2c_stm32f30x.c
@@ -29,9 +29,9 @@
 #ifndef SOFT_I2C
 
 #if defined(USE_I2C_PULLUP)
-#define IOCFG_I2C IO_CONFIG(GPIO_Mode_AF, 0, GPIO_OType_OD, GPIO_PuPd_UP)
+#define IOCFG_I2C IO_CONFIG(GPIO_Mode_AF, GPIO_Speed_50MHz, GPIO_OType_OD, GPIO_PuPd_UP)
 #else
-#define IOCFG_I2C IOCFG_AF_OD
+#define IOCFG_I2C IO_CONFIG(GPIO_Mode_AF, GPIO_Speed_50MHz, GPIO_OType_OD, GPIO_PuPd_NOPULL)
 #endif
 
 #define I2C_HIGHSPEED_TIMING  0x00500E30  // 1000 Khz, 72Mhz Clock, Analog Filter Delay ON, Setup 40, Hold 4.