overheating

[Ohio Blue]

my FJ is heating up pretty quick even if i'm moving the fan kicks on and the engine temp goes up over half. what could the problem be. this is my first liquid cooled bike.

Rick W

 

[Sherman]

my FJ is heating up pretty quick even if i'm moving the fan kicks on and the engine temp goes up over half. what could the problem be. this is my first liquid cooled bike.Rick W

Do you know the bike history? When was the last coolant flush? I just flushed my bikes system, and it runs cooler. Search with the word overheating. 3-4 bars is normal iirc.

Welcome to the nut-house.

 

[uctofeej]

If the fan is coming on and the bars are only just over half, then everything is working normally.

Check out the bin-o-facts

For Gen I bikes: Fahrenheit 1 bar 104-140, 2 bars 140-176, 3 bars 176-212, 4 bars 212-230, 5 bars 230-248, and 6 bars 248 and up

My Gen II runs 3-4 bars above the midway point any time I'm in stop-n-go traffic.

 

[SkooterG]

my FJ is heating up pretty quick even if i'm moving the fan kicks on and the engine temp goes up over half. what could the problem be. this is my first liquid cooled bike.Rick W

Ohio Blue - Hard to tell if you have a problem from the limited info you provide.

Here's how your FJR should work for the most part:

On Gen I FJRs (2003-2005) there are a total of 6 temperature bars. At some point, if (or when) you get to the 6th bar it flashes indicating it's overheating time and you need to do something right away.

Now for the most part, most Gen I FJRs should not ever see the 5th bar.

Normal operating temperature is in the 2-3 bar range if you are constantly moving.

If stopped, or doing a lot of stop-n-go riding, in is not unusual for the system to hit the 4th bar. When that happens, the fan will come on. Depending on outside temps, humidity, and whether or not you are moving, after many seconds to a few minutes the system will go back down to 3 bars, and a short time after that the fan will stop. If you stay in conditons where you are not getting natural air flow through the radiator, the cooling system will keep repeating this cycle. (3 bars to 4 bars, fan on, down to 3 bars, fan off....)

I ride regularly in the desert southwest with temps over 100 degrees and I think I only have seen the 5th bar once in almost 5 years. (Not counting some recent activity where my fan stopped working due to a blown fuse)

In 100+ temps, I will consistently run at 3 bars as long as I am moving. In temps below 90 or so, I will generally run at only 2 bars as long as I am maintaining interstate speeds.

If your FJR is running in the 2-3 bar range, with occasional and short forays to the 4th bar (due to no or limited airflow) then all is righteous in your FJRs world.

If you are hitting the 4th bar and the fan is coming on while you are consistently moving then you may, and I reiterate, *may* have a problem.

So given my description on how the typical Gen I FJR's cooling system operates, how does yours now compare?

 

[Ohio Blue]

my FJ is heating up pretty quick even if i'm moving the fan kicks on and the engine temp goes up over half. what could the problem be. this is my first liquid cooled bike.Rick W

Ohio Blue - Hard to tell if you have a problem from the limited info you provide.

Here's how your FJR should work for the most part:

On Gen I FJRs (2003-2005) there are a total of 6 temperature bars. At some point, if (or when) you get to the 6th bar it flashes indicating it's overheating time and you need to do something right away.

Now for the most part, most Gen I FJRs should not ever see the 5th bar.

Normal operating temperature is in the 2-3 bar range if you are constantly moving.

If stopped, or doing a lot of stop-n-go riding, in is not unusual for the system to hit the 4th bar. When that happens, the fan will come on. Depending on outside temps, humidity, and whether or not you are moving, after many seconds to a few minutes the system will go back down to 3 bars, and a short time after that the fan will stop. If you stay in conditons where you are not getting natural air flow through the radiator, the cooling system will keep repeating this cycle. (3 bars to 4 bars, fan on, down to 3 bars, fan off....)

I ride regularly in the desert southwest with temps over 100 degrees and I think I only have seen the 5th bar once in almost 5 years. (Not counting some recent activity where my fan stopped working due to a blown fuse)

In 100+ temps, I will consistently run at 3 bars as long as I am moving. In temps below 90 or so, I will generally run at only 2 bars as long as I am maintaining interstate speeds.

If your FJR is running in the 2-3 bar range, with occasional and short forays to the 4th bar (due to no or limited airflow) then all is righteous in your FJRs world.

If you are hitting the 4th bar and the fan is coming on while you are consistently moving then you may, and I reiterate, *may* have a problem.

So given my description on how the typical Gen I FJR's cooling system operates, how does yours now compare?

I would say that i have a problem. It was only 80 degrees and i had five bars from sitting at a stop light in no time at all. the bike always stays in the 3 to 4 bar area, even when i am on the highway.

 

[El Toro]

I would say that i have a problem. It was only 80 degrees and i had five bars from sitting at a stop light in no time at all. the bike always stays in the 3 to 4 bar area, even when i am on the highway.

If you're not smelling coolant leakage, and if your overflow bottle is in the normal range when you stop, I wouldn't worry about it.

I'm not sure how precise the digital display is.

I am pretty sure that the FJR, like nearly every other water cooled vehicle, is OK as long as your not leaking, your fan cycles when necessary, and your fan is OFF when your running at normal speeds.

Some simple things to check besides your overflow bottle and general leakage would be to see if there is any kind of obstruction over your radiator (bugs, leaves, candy bar wrapper, 6-pack cardboard), and take a look at your fan when its running to see if its vibrating, or showing other outward signs of a problem.

Obstruction of radiator, Coolant level, leaks, fan failure, or thermostat degradation are all worth a look, but I'll bet you're OK.

 

[madmike2]

Some simple things to check besides your overflow bottle and general leakage would be to see if there is any kind of obstruction over your radiator (bugs, leaves, candy bar wrapper, 6-pack cardboard), and take a look at your fan when its running to see if its vibrating, or showing other outward signs of a problem.
Obstruction of radiator, Coolant level, leaks, fan failure, or thermostat degradation are all worth a look, but I'll bet you're OK.

Check to see that the radiator fins are not full of road grime.

Make sure the cooling system is "topped off".

Has anyone flushed the system and refilled with coolant? If so, could there be an air bubble in the system. Look at https://www.fjr-tips.org/ (Bounce's site) for the proper way to clean and refill the cooling system.....and other great maintenance tips.

My '05 runs consistently @ 3-4 bars in amy weather above Winter cold. In temps above 80-85 degrees, it will climb to 5 bars at an intersection and the fan comes on. I don't think you have a problem.

 

[SkooterG]

My '05 runs consistently @ 3-4 bars in amy weather above Winter cold. In temps above 80-85 degrees, it will climb to 5 bars at an intersection and the fan comes on. I don't think you have a problem.

Really? Are you sure?

Every other description of the cooling system I have seen on here for a Gen I has said the fan comes on at 4 bars.

Anyone else out there see 5 bars? If so how often? And does anybody else out there have a Gen I where the fan does NOT come on at 4 bars and go off at 3?

Obviously, there can be variances, but after riding many FJRs, I have not seen it in regards to the cooling system.

 

[Joevelocity]

My '05 runs consistently @ 3-4 bars in amy weather above Winter cold. In temps above 80-85 degrees, it will climb to 5 bars at an intersection and the fan comes on. I don't think you have a problem.

Really? Are you sure?

Every other description of the cooling system I have seen on here for a Gen I has said the fan comes on at 4 bars.

Anyone else out there see 5 bars? If so how often? And does anybody else out there have a Gen I where the fan does NOT come on at 4 bars and go off at 3?

Obviously, there can be variances, but after riding many FJRs, I have not seen it in regards to the cooling system.

Even on the hottest days 90+, in traffic, I don't see 5 bars.... Fan comes on at 4 and off at 3 bars.

 

[Sherman]

I did the coolant flush and only get 2 bars mostly, but the frame near the steering head is too hot to touch after a brief ride (on low fuel.)

Is that normal? Maybe my system has air in it?

 

[SkooterG]

I did the coolant flush and only get 2 bars mostly, but the frame near the steering head is too hot to touch after a brief ride (on low fuel.)Is that normal? Maybe my system has air in it?

Normal. Frame is a heat sink on the FJR. As long as your temp gauge is showing operation in normal range your good to go. Pretty rare for the FJR to get air in the cooling system. Due to some recent cooling problems of my own, I am a lot for familiar with it. There is a hose that goes from the thermostat to just under the radiator cap that is called the 'thermostat vent line' and it is pretty effective and bleeding any air out of the primary part of the system.

 

[madmike2]

My '05 runs consistently @ 3-4 bars in amy weather above Winter cold. In temps above 80-85 degrees, it will climb to 5 bars at an intersection and the fan comes on. I don't think you have a problem.

Really? Are you sure?

Every other description of the cooling system I have seen on here for a Gen I has said the fan comes on at 4 bars.

Even on the hottest days 90+, in traffic, I don't see 5 bars.... Fan comes on at 4 and off at 3 bars.

Of course you two are correct. I just went out and turned on the key....DOH! I was thinking 1 bar above half-way and somehow my brain thought 5 bars when it is actually 4 bars that triggers the fan.

 

[08FJR4ME]

My Gen II runs 3-4 bars above the midway point any time I'm in stop-n-go traffic.

08FJR, I have only herd the fans come on 3 times and 2 of the three times was after i turned the bike off and then restarted it. (gas stops)

Last week we briefly hit the 8'th bar. Hit the seventh bar several times that day. City traffic mostly. Stopped at the local Yami dealer and he couldn't tell me what the temps were for each bar. He would call the rep and try to find out. "was told unless you smell it boiling over dont worry about it." in actuallality it did boil over the previous week. Started the bike up at lunchtime to let it warm up and the phone rang. I then went back in to answer it and got tide up for about 5 to ten minutes. When i got back out to the bike i could smell the antifreeze but nothing on the ground. I looked at the overflow tank and it is about 3/8 of an inch below the top line. " normal range" and by the way no fans were running at this time. So i got on the bike and got going to get some air thru the radiator and let it cool down. She went back down to normal 4 to 5 bars. I looked in the bin o facts and it looks like the temps listed are for GenI bikes. Does anybody now what the temps are for each bar on the GenII's?

 

[03HiYoSilver]

My Gen II runs 3-4 bars above the midway point any time I'm in stop-n-go traffic.

08FJR, I have only herd the fans come on 3 times and 2 of the three times was after i turned the bike off and then restarted it. (gas stops)

Last week we briefly hit the 8'th bar. Hit the seventh bar several times that day. City traffic mostly. Stopped at the local Yami dealer and he couldn't tell me what the temps were for each bar. He would call the rep and try to find out. "was told unless you smell it boiling over dont worry about it." in actuallality it did boil over the previous week. Started the bike up at lunchtime to let it warm up and the phone rang. I then went back in to answer it and got tide up for about 5 to ten minutes. When i got back out to the bike i could smell the antifreeze but nothing on the ground. I looked at the overflow tank and it is about 3/8 of an inch below the top line. " normal range" and by the way no fans were running at this time. So i got on the bike and got going to get some air thru the radiator and let it cool down. She went back down to normal 4 to 5 bars. I looked in the bin o facts and it looks like the temps listed are for GenI bikes. Does anybody now what the temps are for each bar on the GenII's?

From the Bin 'O Facts:

There are 10 segments on the coolant temperature bar graph/display for Gen II FJR's. (Gen 1's have 6 bars)

Estimated bar to temperature conversion (otrfjr) (i.e. using the '05 values and dividing by 10)

Basis: If 1 bar = 104 (degrees Fahrenheit) and 6 bars = 248; for 10 bars >> then 248-104 = 144/10 = 14.4/per bar.

Estimations based on Gen 1 data:

1 = 104.0 - 118.4 (deg. F)

2 = 118.5 - 132.9

3 = 133.0 - 147.4

4 = 147.5 - 161.9

5 = 162.0 - 176.4

6 = 176.5 - 190.9

7 = 191.0 - 205.4

8 = 205.5 - 219.9

9 = 220.0 - 234.4

10= 234.5 - 249.9+

So based on this info for a GENII, this is not a problem.

 

[Warchild]

Even on the hottest days 90+, in traffic, I don't see 5 bars.... Fan comes on at 4 and off at 3 bars.

This is indeed the correct behavior, certainly for Gen I bikes.

 

[Warchild]

I did the coolant flush and only get 2 bars mostly, but the frame near the steering head is too hot to touch after a brief ride (on low fuel.)Is that normal?

Yes, it is completely normal, especially during summer.

The FJR's frame is actually a main contributor to the "heat issue" a number of Gen I owners (and some Gen II) complain of.... radiative heat transfer right onto the thighs and lap of the rider.