The ONLY valid reasons to be concerned about on the KLR cooling system are:
- Temperature gauge swings that are outside of the normal operating range
- The temperature differential between the top and the bottom of the cylinder (which could cause uneven wear)
- A bottom end that doesn't get to operating temperature.
The reason these issues happen is the stock cooling system lets HOT water out of the head and draws only cold water into the bottom of the cylinder through the water pump, from the radiator.
These are the main reasons to get the MCP Thermal Control System and the ONLY valid reasons to get a bypass mod.
Not all bypasses are alike and only the MCP system addresses all the concerns pointed out above.
The MCP Thermal Control System (MCP TCS), works most noticeably better than other similar mods in extreme heat or cold, transferring more heat between the bottom and top ends in both directions. In extreme heat the MCP TCS cools the bottom end, in extreme cold it warms the bottom end all the while keeping the top end temperature even.
The MCP Thermal Control System recirculates the right amount of coolant to reduce shear points in the water jacket which promotes mixing, therefore reducing hot spots keeping the entire top end the same consistent temperature. This also promotes more accurate gauge readings.
Having the bottom end (and engine oil) at operating temperature makes the transmission shift much smoother.
The MCP Thermal Control System also keeps the radiator cooler at all times compared to similar mods. This means there is more cool water available for engine cooling. This will also make your KLR take longer to start heating up in stop and go traffic
The needle anywhere between the white lines is normal. The top of the range is the fan activation temperature, the bottom of the range is thermostat temperature. The KLR has a low capacity cooling system (especially Gen 1), there is a small temperature range on the gauge, this means the needle moves a fair bit which is normal and expected.
The needle position shown in the picture is normal operating temperature for the KLR with the stock 160 degree thermostat and with adequate air movement through the radiator. The needle will be a little higher than pictured if it is hot outside, and a little lower if its cold out (1 needle width). This is where the gauge should run most of the time, exception is when moving slow or with a big tail wind.
The stock cooling system doesn't heat the bottom end to operating temperature in cooler ambient temperatures which allows condensation to collect.
The MCP Thermal Control System (MCP TCS) heats the bottom end to operating temperature, like the top end, when riding in cooler weather which cooks off the moisture not allowing it to collect.
The moisture is pushed out the crankcase breather and is burned off through the motor.
