Running a little hot

[delfox]

Hi all.. i have sold my faired fz6 and purchased a naked fz6 with less miles 15,800 to be exact.. i have noticed when im riding the temp gauge stays at the halfway mark.. and sometimes drops when i hit speed obviously cooling with the cold air. it will rise when in standing traffic and if i leave it idling in the garage the fan kicks in as normal and cools it.. now my old fz6 temp gauge usually stayed just one bar under halfway mark and ran the same as above.. i was just wondering copuld the mixture on the new bike be a little lean causing the temp gauge to stay at halfway mark rather than my old bike staying just under halfway.. also when ive been riding it.. the rear light feels warm from the exhaust heat.. any help would be appreciated. thanks

 

[agf]

Hi
I don't have anything concrete to pass on but I would say that each bike will have it's own peculiarities and what one bike will feel normal another will be high/low.
I would think unless you are happy to service the bike yourself, have it serviced by a dealer to put your mind at rest that everything is set as per specs.

 

[delfox]

i was thinking the same thing. it runs fine.. its just that the temp is running one bar higher than my old bike. but im gonna get the throttle bodies looked at as most answers are saying it could be the mixture. Thanks for the reply

 

[Gary in NJ]

I would say it’s simply a variation in the gauges since the fans aren’t running high during normal operations.

 

[bigborer]

It's definitely not normal to have large variances on Japanese bikes...

Higher temps could be caused by:
-loss of pressure: air inside the system / faulty radiator cap (leaks pressure) / faulty hoses or connections
-scaling/deposits/corrosion inside the cooling system
-bad/old coolant
-defective thermostat
-defective temp sensor
-corroded fan / temp sensor / thermostat connectors

Over the years (multiple vehicles) I've had all of the above happen, except for the temp sensor.

To begin with I'd inspect the radiator cap (is the spring corroded? is the rubber seal cracked or very hard?), drain the old liquid, run water with a garden hose at medium-high pressure through the radiator cap, reconnect everything and run it for 10 minutes with distilled water, drain again and put new coolant, and spray some contact cleaner and apply dielectric grease (also found as "battery terminal grease") on the fan / temp sensor / thermostat connectors.

 

[delfox]

It's definitely not normal to have large variances on Japanese bikes...

Higher temps could be caused by:
-loss of pressure: air inside the system / faulty radiator cap (leaks pressure) / faulty hoses or connections
-scaling/deposits/corrosion inside the cooling system
-bad/old coolant
-defective thermostat
-defective temp sensor
-corroded fan / temp sensor / thermostat connectors

Over the years (multiple vehicles) I've had all of the above happen, except for the temp sensor.

To begin with I'd inspect the radiator cap (is the spring corroded? is the rubber seal cracked or very hard?), drain the old liquid, run water with a garden hose at medium-high pressure through the radiator cap, reconnect everything and run it for 10 minutes with distilled water, drain again and put new coolant, and spray some contact cleaner and apply dielectric grease (also found as "battery terminal grease") on the fan / temp sensor / thermostat connectors.

i looked at the radiator cap and the outer seal has 3 splits in it.. im guessing this could be the problem

 

[bigborer]

Notice that there is some scaling. I'd definitely rinse and flush the cooling system as described in my previous message. Also make sure to scrub clean the radiator at the cap region, to ensure the surface will be smooth and scale/dirt free in order to provide the best seal.

For replacing the cap you could also go to any local car parts store and buy a cap of the same size and pressure rating (I think 1,1 bar, but check for yourself first) for 10-20% of the cost of an OEM one.

 

[Motogiro]

^^^^^This!^^^^
Flush and renew the coolant. The water which is 50 percent of the coolant mix is probably depleted. The water is the element that cools better compared to the glycerine in the coolant.
Also flushing possible scale contaminates aids in the heat transfer from the engine alloy to the coolant improving cooling. Also inspect hoses and refill overflow recovery canister. Make sure the system has no air trapped. Sometimes tilting the bike gently side to side when first filling helps get air out.. Check over flow recovery when cold to see if any air has been burped and replenish coolant as needed.

 

[delfox]

Thanks guys.. i have ordered a new OEM radiator cap and as soon as that arrives i will flush the coolant and put new stuff in.. watch this spaceBlah