TOPIC:

After a bit of reading sort of found my answer. The thermostat only starts to open between 172F and 187F. Maximum lift of the thermostat is only obtained when the engine reaches 203F.

This means the thermostat isn’t opening fully across all temperature ranges but it works and the engine stays cool.

Hi Martin,

from reading below I understand you are using 190f - 175f fan switch and the original thermostat
do you see any problem with this setup?

Thank you

mizztheman wrote: After a bit of reading sort of found my answer. The thermostat only starts to open between 172F and 187F. Maximum lift of the thermostat is only obtained when the engine reaches 203F.

This means the thermostat isn’t opening fully across all temperature ranges but it works and the engine stays cool.

I feel like I need to inject a little theory here.
Under normal conditions, traveling down the road cruising along, the thermostat will open and exchange coolant with the rad to keep the engine at operating temperature. If your just cruising, the air movement across the rad will dump enough heat to keep the system happy and there should be no need to energize the fan.
Now let's say you just came in off the highway and pulled up to a traffic light. A lot of heat stored in the coolant and no air flow across the rad. Time for the fan to come on and assist dumping the heat.
Another scenario, you're hot dogging it in town and a lot of stop and go traffic. Lots of heat and no airflow. Need the fan.

So, the standard thermostat operates between 172F-187F in a mixed flow set up and if you manage to get up to 203F the thermostat is in full bypass. What happens if you get over 190F and the fan comes on and you never get below 175F because the thermostat is now in the mixed flow range? The fan won't shut off.

This why I said, if you opt to go with a lower thermostat (180F), you could use the 190F on 175F off and get your operating temperature in a lower range.

You could go ahead and install your new fan switch and try it out with the standard thermostat and no harm will come, but my gut is telling me that you may find yourself in a situation where the fan is constantly running and please note that the charging circuit is barely adequate for the needs of the bike. A constantly running fan is definitely not desired.

Thank you Kawboy,

I will try and see, If the fan stay on constant or I feel is working too much I will change the fan switch, easier then changing the thermostat
at this point I really want to see this bike on the road already...

BTW, below is from Zed-Parts website
they sale aftermarket with temp 190f - 180f and don't mention anything about the thermostat

27010-1026 Fan Temp Switch
£46.75Price
27010-1026ZP This is our own fan switch for the z1300- a simple unit to just screw in and connect with the original wire, no need for extra connectors.

As a direct replacement to the original, these are made in Italy

Temp range is 87opening and 82 closing.

17mm A/F Spanner

Kawasaki's replacement for the original 27010-1026 fan switch that was superseded to 27010-1036 does not open until 110 degrees, and may trigger the fan to come on too late.

On testing this switch we had the fan coming on at the letter"E" on the TEMP guage.

Due to the cost of replacement, we only send this item signed for ,if you choose unsigned we are unable to replace if the postal system fails to deliver.

Hi bar,
I fitted the new switch about 3 months ago with no obvious problems.

I partly agree with what Kawboy is saying about charging issues with the fan being on most of the time but this would depend on how the bike is being used. For me, I live on the outskirts of town so it’s not very often I encounter slow moving traffic as I have direct access to the dual carriageways and motorways before I get to my favourite country roads in North Wales. I can see how it would be a problem if you are commuting around towns and cities at low speed with little chance of getting the engine revs up to ensure the battery is getting a good charge.

By the way, I had a look in the manual to see how much current the fan motor draws but can’t find anything.

Regards

Martin