I know this has a thermostat but,

My 2003 FJR is running hot and I think it needs a new thermostat. I can't find one to replace it with, am I nuts? If I ride this bike a short distance, it starts to get hotter than it ever has on the same trip. Where do I get a new thermostat or, is there something wrong with it otherwise? Yes I have changed the anti-freeze in it last year.

Here

Rare, but thermostats have been known to jam.

You can test it by placing it in a pot of water, with a kitchen thermometer, then heat the water and observe if it opens when it should

71 - 85 C (159.8 - 185.0 F)

thanks. Any other ideas to what is going on?

The troubleshooting section of the FSM:

Overheating

Engine

• Clogged coolant passages
• heavy carbon buildup in cylinder heads and pistons

Engine oil

• incorrect oil level
• incorrect oil viscosity
• inferior oil quality

Cooling system

coolant

• low coolant level

Radiator

• damaged or leaking radiator
• faulty radiator cap
• bent or damaged radiator fin
• damaged or faulty water pump
• themostat stays closed
• clogged or damaged oil cooler
• damaged hose
• improperly connected hose
• damaged pipe
• improperly connected pipe

Check the simple stuff first, such as coolant level -- make sure the system is burped, for example, so there's no air bubbles preventing proper function, then check for leaks at the connection points etc.

thanks Silver spirit, that is what I will be doing the rest of the day!

I have been told to "burp" the system, how do you do that?

this old post may help you if you decide to go ahead

https://www.fjrforum.com/forum/index.php?showtopic=137232

Luis

What you mean running hot?How many bars you see in the gauge?The three bars is pretty normal for the Gen1 some times even in the highway when the temperature is around 35C+.In the city the three - four bars are also normal..

Mihalis fjr said:

What you mean running hot?How many bars you see in the gauge?The three bars is pretty normal for the Gen1 some times even in the highway when the temperature is around 35C+.In the city the three - four bars are also normal..

Click to expand...

Well, when I first bought this it was usually on 2 bars. The last 2 days when I have looked, it was on 3 bars. It just didn't seems normal to me. I do know that in the city, it runs on 3 bars until you get it moving. On the highway it does run on 2.

Note that if you do decide to check the thermostat, the Gen I thermostat is in a different location from the Gen II. It is located just above and ahead of the engine, not on the side. If you don't have a FSM, (and you really should!), check the fiche view at that link I provided.

As Mihalis fjr notes, your bike might not be overheating anyway.

The LINK silver spirit meant to provide.

Semper Fi said:

Mihalis fjr said:

What you mean running hot?How many bars you see in the gauge?The three bars is pretty normal for the Gen1 some times even in the highway when the temperature is around 35C+.In the city the three - four bars are also normal..

Click to expand...

Well, when I first bought this it was usually on 2 bars. The last 2 days when I have looked, it was on 3 bars. It just didn't seems normal to me. I do know that in the city, it runs on 3 bars until you get it moving. On the highway it does run on 2.

Click to expand...

I believe that your bike is pretty normal!Perhaps when you saw the three bars on the gauge,the air temperature was a bit higher from the other days..I wouldn't touch anything...

Hey Semper Fi, my Gen 1 runs at 2 bars on the highway but when I slow down it goes to 3 and if I do 2 or 3 minutes in stop & go traffic it will go to 4 bars

and the fan will kick in. Once under way again it drops to 3 bars & fan goes off. Sometimes it will take a few miles of highway speed to drop from 3 to 2

bars. NOT TO Worry it is fine and the temp here lately has been over 100 deg F. clean the dead bug guts off your radiator.

Mihilas has been known to stop at every bar on the road, so he may be showing 13 to 14 bars by the end of the day.

Sounds normal range to me. Splitting hairs about a partial bar....I'd check for bugs too. 5 or under and it's in the normal range IMO.

Douche the hell out of the radiator fins with a squirt bottle full of hydrogen peroxide. When you think it's saturated, douche it some more. Rinse them off with a water hose with gentle pressure. You'd be surprised at what thousands of dead bugs will do to your airflow.

Then go ride!

I have noticed than my '05 has been running a little hotter the past few years than it did when new. The only time I worry about it is when the fan is running a lot and the voltage starts to drop. I am more concerned about a dead battery then overheating.

Geezer said:

I am more concerned about a dead battery then overheating.

Click to expand...

Because Yamaha engineers purposely added a device to the motorcycle that exceeds your alternator output and could leave you stranded? A fan is probably about 60 watts. Your alternator is 490 watts. Even if it were on all the time you wouldn't be at risk of a dead battery.

Ignacio said:

Geezer said:

I am more concerned about a dead battery then overheating.

Click to expand...

Because Yamaha engineers purposely added a device to the motorcycle that exceeds your alternator output and could leave you stranded? A fan is probably about 60 watts. Your alternator is 490 watts. Even if it were on all the time you wouldn't be at risk of a dead battery.

Click to expand...

I don't know how many watts the fan draws, but I do know that the voltage drops when it is on, and continues to drop as long as it is running. And yes, it is possible for Yamaha engineers to purposely add a necessary device that exceeds the alternator output at the low RPMs that are common when sitting in traffic. I don't remember the fan ever coming on while I was running close to 5000 RPM.

Geezer said:

And yes, it is possible for Yamaha engineers to purposely add a necessary device that exceeds the alternator output at the low RPMs that are common when sitting in traffic.

Click to expand...

Well then as an anecdotal dissenter I'll add that I've left my '05 idling for over an hour before in a parking lot one summer with fan running most of the time, finally turned off the bike, and it started right back up 15 minutes later. I'm pretty sure at even idle the alternator isn't in a deficit situation because of the fan and other stock bits.