Hi guys, my fiance's bike is an 03 f4i, its a great little 600 and has 9200 miles on it. We recently had a dealer do a coolant flush and regular service, I know that her bike heats up a lot differently and runs a bit hotter than my k5 gsxr 1000.

Here's the problem: recently, she was riding and the temp got up to 242. She pulled over and it went down a bit and got it home to the garage where I had a look at it. I started it up later, drained some coolant out and added water wetter (only about 2 oz). Started it up and got it up to running temp to see when the fan would come on. The fan didn't come on until it would hit/surpass 230F. I've done multiple searches on forums and seen that it should come on at 220F.

Any ideas on what's wrong? If it was a blown fuse the fan wouldn't turn on at all, so I don't understand what's up. I know that it's good that the fan comes on, but in stop and go traffic, I know its just a matter of time when the summer comes before it will hit 250+ and problems will arise, this can't be normal even for a hotter bike.

 

thats normal....my fan kicks on somewhere between 225 and 229......230 even 240 is expected for stop and go traffic.....goin 80 on the freeway though it should be fine.....my normal temp at a decent cruising speed is somewhere in the 180s or 190s......these bikes do run hotter than others though, but not to worry....

what coolant did the dealer use if u mind me asking.....I was under the impression water wetter was to be used only with distilled water.....

some good combos i know for coolant

-distilled water
-distilled and water wetter
-all engine ice
-half and half regular coolant and distilled...

 

Honda's run hotter, mine runs better when it hits 225, if at a stop light it will get even hotter than that, from sitting for a few minutes. On a hot summer day, I will turn the bike off if I know its a long light. All it takes is to get the bike moving and some air to cool it down. Nothing to be too concerned about.

 

225 - 230F is the typical kick in range ofmy fan. You might just want to check that the thermostat opens closes freely. Else, I don't think its a bother.

 

OK. so you guys are saying that coolant temps up to 242 are normal for stop and go traffic on a 75-80 deg. florida day?

Won't the head gasket warp when the coolant hits in the 250s b/c of heat?

 

I would try a coolant flush to be safe to try to keep the temps down a few degrees, does sound a little warm for a 75-80 degree day. I believe the highest temp my 600 has ever seen was 242, but that was on a 95 or so degree day stopped for a while. If I remember right my fan kicks on at 222, but I have an rr the f4i may be a little different. When my old roommate moved to florida he wired a switch that turns the fan on so he could run it all the time, he said it helped.

 

the same thing was wrong with my bike i rode it for like 3 hours kinda in traffic time it got to 237 and the fan cut on and at 225 it cut off. took it to the shop ran the coolant pressure test everything checked out fine. but i wanted to put a manual fan switch on there so i did that just to be safe and not let it get so hot

 

could anyone direct me to a good quality, complete 'how to' on a manual switch install?

 

this is not normal. I have the same problem and have done lots of research on it.

I have replaced my fan switch, thermostat, coolant, and my fan doesn't come on until about 232. It should come on at around 223-225. On a normal operating bike, you should rarely see your temperature go over 230.

With that said, your fan switch is in a cooler area: In the radiator. It will not ground and kick on the fan until about 205F or so. The display you read on the dash is from the temperature sender unit next to the thermostat. The temperature next to the thermostat is when the fluid exits the engine area and heads back to the radiator to cool.

Now, I have talked to many tech guys at honda. They rarely say the thermostat is the culprit, instead, they say that the temperature probe near the thermostat crap out all the time, and that is most likely the culprit.

To test this theory, you should turn your bike on with the radiator cap off. If the coolant starts to rise once the bike hits about 160 or so, that's a good indication that your thermostat is working properly. Make sure all of the air is out of the system before you put the cap back on of course.

I have not replaced my temperature sender unit yet, but I have a strong feeling that my bike is not overheating. I have let the temperature come up to near 250 and she has shown no signs of boiling over, therefore, i am getting false readings. I'm going to replace my sender unit at some point this summer... when i get around to it.

 

I never said 242 was normal, I stated that my bike has gotten up there. The hottest my bike got was 262 and it ended up burning up my clutch plates. On a hot summer day, I average the hottest of 230 in town and once my bike gets moving, the cool air lowers the temperature.