Q Why is my Tracer blowing hot and cold?
The coolant temperature of my Yamaha MT-09 Tracer seems to vary a lot. It generally runs at 70 degrees, up to 105 degrees in traffic before the fan cuts in, but got down to a surprising 55 degrees at 70mph on the motorway in some recent rain. Is this OK? Launce Morgan, email
Answered by Chris Dabbs, MCN The issue with any engine is overheating, and as long as your fan is cutting in when the temperature climbs there is no problem. Even though most bikes are liquid-cooled, they aren’t like cars with a massive radiator to dissipate heat, and need airflow to keep them in the sweet spot. The same bike is also sold in markets with a much hotter climate than the UK, so bikes can run cooler here. Yamaha’s Super Ténérés and the first TDMS were quite ‘cold-blooded’ and you were lucky to see 70 degrees in the UK. I’m surprised that the temperature got as low as 55 on the motorway, but that could have been because you checked it just as the thermostat opened and the temperature dropped temporarily as colder coolant flowed past the sensor.