Weird temp problem on my F4i

nags · 01-31-2006, 5:56 PM

On my F4i I've had a problem with the temperature on it since I got it. It'll jump around.. Like.. it'll go 140..144..142..146..142.. etc

It'll usually stay within a few degress of where it should be but its always jumping around on the way up. I've changed the temp sensor on both the radiator and the thermostat. I've tried another set of gauges and even another ECU. It doesnt seem to affect the way the bike runs or anything but it's just annoying me.

Any ideas as to what it may be?

thanks,
nags

gt702 · 02-01-2006, 3:58 PM

Quote:

Originally Posted by nags

On my F4i I've had a problem with the temperature on it since I got it. It'll jump around.. Like.. it'll go 140..144..142..146..142.. etc

It'll usually stay within a few degress of where it should be but its always jumping around on the way up. I've changed the temp sensor on both the radiator and the thermostat. I've tried another set of gauges and even another ECU. It doesnt seem to affect the way the bike runs or anything but it's just annoying me.

Any ideas as to what it may be?

thanks,
nags

Does it do this while sitting idling, or during normal riding? As long as your radiator is properly filled (no air bubbles or anything), there should be nothing wrong. If you don't like the numbers changing, tape over it

BTW, 140's seem pretty low to me. If that is where you are running, you don't need to have the fan on all the time.

RRWANTR · 02-01-2006, 4:04 PM

You expect the temp to stay exactly the same at all times?!?!

nags · 02-01-2006, 4:06 PM

Quote:

Originally Posted by gt702

Does it do this while sitting idling, or during normal riding? As long as your radiator is properly filled (no air bubbles or anything), there should be nothing wrong. If you don't like the numbers changing, tape over it

BTW, 140's seem pretty low to me. If that is where you are running, you don't need to have the fan on all the time.

At all times.. even while riding

I was just using 140s as an example as the bike was warming up while I was watching it right before this post...

nags · 02-01-2006, 4:07 PM

Quote:

Originally Posted by RRWANTR

You expect the temp to stay exactly the same at all times?!?!

No, but I also have a 929 and 954 and I've never seen the temps jump back and fourth 5 degrees at a time for no reason

RRWANTR · 02-01-2006, 4:17 PM

How quickly? My 954 and 600rr were/are always changing...

nags · 02-01-2006, 4:22 PM

Quote:

Originally Posted by RRWANTR

How quickly? My 954 and 600rr were/are always changing...

They go up 1 or 2 degrees at a time.. they never jump back 5 degrees without the fan coming on or anything

RRWANTR · 02-01-2006, 4:23 PM

Quote:

Originally Posted by nags

They go up 1 or 2 degrees at a time.. they never jump back 5 degrees without the fan coming on or anything

Absolutely normal (at least with every bike I've ever ridden/seen).
Why do you think it's abnormal? What's your 954 do?
edit...I just reread and you were talking about the 1 to 2 deg in regards to the 954 and 929 weren't ya? Mine will go down up and then down though as I ride depending on amount of air going through based on speed etc..

nags · 02-01-2006, 4:29 PM

Quote:

Originally Posted by RRWANTR

Absolutely normal (at least with every bike I've ever ridden/seen).
Why do you think it's abnormal? What's your 954 do?
edit...I just reread and you were talking about the 1 to 2 deg in regards to the 954 and 929 weren't ya? Mine will go down up and then down though as I ride depending on amount of air going through based on speed etc..

It's just weird that I can sit with the bike in neutral and hold the throttle at 5k... Instead of going straight up. the temp will drop down 5 degrees here and there

It's not a big deal.. The bike runs fine. I was just wondering as I've never had a bike do this before

RRWANTR · 02-01-2006, 4:33 PM

Quote:

Originally Posted by nags

It's just weird that I can sit with the bike in neutral and hold the throttle at 5k... Instead of going straight up. the temp will drop down 5 degrees here and there

It's not a big deal.. The bike runs fine. I was just wondering as I've never had a bike do this before

At idle dropping like that is kinda weird.

BDA116 · 02-01-2006, 4:45 PM

It would drop at first, as it is spinning the water pump quicker and thus removing heat from the engine when holding it a 5K RPM, but once the bike got fully warmed up and the water was all hot without air moving through the radiator it would rise rather than fall.

gt702 · 02-01-2006, 4:52 PM

Quote:

Originally Posted by nags

It's just weird that I can sit with the bike in neutral and hold the throttle at 5k... Instead of going straight up. the temp will drop down 5 degrees here and there

It's not a big deal.. The bike runs fine. I was just wondering as I've never had a bike do this before

Probably running into the point where the thermostat opens and closes. It might open and close (chattering) a little until the water warms up enough to keep it open. A slug of cold water can close the thermostat again until it heats up again. I've seen this a couple times under certain conditions; definitely not something to be worried about ... just don't look at the dash until it is warm

fat2k3 · 02-07-2006, 2:14 AM

Quote:

Originally Posted by gt702

Does it do this while sitting idling, or during normal riding? As long as your radiator is properly filled (no air bubbles or anything), there should be nothing wrong. If you don't like the numbers changing, tape over it

BTW, 140's seem pretty low to me. If that is where you are running, you don't need to have the fan on all the time.

140 seems crazy low to me...My F4i is usually mid 180's, but will hit 220(Fan engages about then!) at a long signal or just while parking in my office garage.

Remember, that little sucker is pumping out some RPM's, and it's a lot happier in the wind!

I vote for the tape!

nags · 02-08-2006, 10:40 AM

Ok, so I just rode the bike for the first time and the temp is jumping like 20 degrees at a time.. it'll go from 190 to 212 and them back down to 185 all within 5 seconds

cvc14 · 02-09-2006, 9:04 PM

Quote:

Originally Posted by nags

Ok, so I just rode the bike for the first time and the temp is jumping like 20 degrees at a time.. it'll go from 190 to 212 and them back down to 185 all within 5 seconds

The bike is just trying to remind you that you have a Honda nut roaster which you are sitting apon. Just dont hope it will keep you warm on a cold night ride b/c that will never happen. It just like to burn you balls when it is hot out.

When it goes from 212 back down to 180 are you..
1. riding the bike so air is passing over the rat and cooling things off?
or
2. the fan is kicking on and cooling things down?

If it is either one of those dont worry about it b/c it is completly normal. My bike will get up to 225 before it comes back down.

nags · 02-14-2006, 8:35 AM

Quote:

Originally Posted by cvc14

The bike is just trying to remind you that you have a Honda nut roaster which you are sitting apon. Just dont hope it will keep you warm on a cold night ride b/c that will never happen. It just like to burn you balls when it is hot out.

When it goes from 212 back down to 180 are you..
1. riding the bike so air is passing over the rat and cooling things off?
or
2. the fan is kicking on and cooling things down?

If it is either one of those dont worry about it b/c it is completly normal. My bike will get up to 225 before it comes back down.

Nope..the bike is sitting in my driveway idling.. Fan wasn't even on yet

fat2k3 · 02-16-2006, 10:40 PM

Maybe you have a bogus sending unit or a pinched wire?

smirk43 · 03-09-2006, 6:37 PM

Might be a long shot, but switch your coolant to water wetter or engine ice & see if it's still jumping...

drinktoo · 03-09-2006, 7:11 PM

Quote:

Originally Posted by smirk43

Might be a long shot, but switch your coolant to water wetter or engine ice & see if it's still jumping...

I got the same problem after changing the fans temperature sensor in the radiator, but the temp used to go up at a reasonable rate before. I used a temp sensor from another Honda, but since both the f4i and the other bike showed the same part number I picked it up. OBT this is my track bike and it does have water wetter in it. I'm not worried about it because the bike is a track bike and is in the wind for most of its running time. The fan also kicks in at around the right temp, so I think it has something to do with how the guages are picking up the signal from the sensor.

nags · 08-22-2006, 10:56 PM

Ok, so after this thread and doing everything I could think of.. I decided to just deal with it

Well, a few months later it's still driving me crazy and I want to figure out what it is..

Anyone got any other suggestions?

nags · 09-02-2006, 4:33 PM

bump?

seamus · 09-02-2006, 8:53 PM

Quote:

Originally Posted by nags

bump?

Up/down movement of a few degrees is normal as the water/coolant will never be equally hot at idle/low speed operation.

If you're really worried about it, you can flush your system and put some new coolant in it.

Repeater · 09-02-2006, 9:15 PM

tape!

booracer · 09-02-2006, 9:24 PM

sounds like your t-stat is sticking or air pockets in the cooling system.

nags · 09-03-2006, 12:58 AM

Quote:

Originally Posted by seamus

Up/down movement of a few degrees is normal as the water/coolant will never be equally hot at idle/low speed operation.

If you're really worried about it, you can flush your system and put some new coolant in it.

It's not a few degrees.. I was riding last night.. at about 60mph consistent in cool weather the temp reading would go from 160 to 240 back down to 170 all within a 2 second period.

I've since flushed the whole system again and that didnt fix it and I swapped the thermostat

seamus · 09-03-2006, 10:17 AM

That's a lot different than your original post. That is a large jump.

Because the temp is going all the way down to 160 (which seems extremely low), I'd check the temp sensor/sending unit first, followed by trying to "burp" air out of the system (again). If it's not either of those two, since you've already swapped the thermostat, you're going to need some more intimate teardown help.

edit: Also, if your temp was actually going up to 240, you'd most likely be dumping coolant overboard due to expansion. That will also tip you off to the sensor not giving you the right reading.