Kawasaki Ninja ZX-6R Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
44 Posts
Discussion Starter #1
Hi all

Done a track day today, cut it short because the bike was getting really hot, yes it was a hot day 30 deg C, came in after one session and coolant was coming out from the expansion tank hose, temp guage was showing 115 deg, the fan is working with the bike running but although it was very hot, the fan did not carry on running when I when I stopped the bike but the ignition was still on, also noted temp started flashing HI

Any help gratefully appreciated

Cheers Rob
 

·
Registered
Joined
·
44 Posts
Discussion Starter #2
Could anyone confirm that the fan should still come on with just the ignition turned on when the bike is hot

Regards Rob
 

·
Registered
Joined
·
13,454 Posts
Engine off, water pump stops circulating coolant. The fan responds to the temperature sensor which is in most cases just inside the mounting point for the thermostat. It may not read an accurate temp when the coolant stops flowing.

That's a separate issue from the bike running very hot.

The radiator may be clogged with debris In the fins, you could have an air pocket in the system, your water pump may be failing..... Your radiator cap may not be holding enough pressure.

Most of these can be checked at little or no cost. Cheapest to most expensive:

Look at the fins in your radiator. Anything that blocks airflow needs to be corrected. Everything is thin, fragile aluminum. Gentle! A standard garden hose, gently sprayed at the backside of the radiator will flush out dead bugs and other light junk. Then, look at the fins from the front. Any bent ones block airflow. A wooden toothpick, and a lot of patience go a long way... No cost, just time.

Air trapped in the hoses will cause cavitation and vapor locks. No coolant flow means high temperatures. A solid stream of coolant will pull itself all the way around the system. Bubbles occur in the reversed 'elbows' in the hoses. This one may make you buy additional coolant.

Once you've done both of these, if you still have an overheating issue, a new higher pressure radiator cap may help. Higher (or proper) pressure increases the transfer of heat from the metal, into the coolant. The cost of a cap is probably slightly more than the cost of coolant.

If all of those don't solve it, check to make sure the bike is running rich enough. Lean fuel air mixtures run hot. So do altered ignition timimg. Might require a dyno with an exhaust gas analyzer.

Then, and only then, consider the water pump. Along with other mechanical issues. If you inspect the water pump, look at the hole at the bottom edge. Should be dry. If you see coolant dripping out of that hole, you have proof of a failing pump. Rebuild.
 
1 - 5 of 5 Posts
Top