Ran really hot today

After much searching I have been unable to locate anything on what might be causing my 2005 midnight to run hot today. Went for a ride with two friends (on Harleys) today and got into stop and go traffic on a side trip to Ocala. The temp gage (Sunpro small triple set) started going up and up and up till it was pointed at the six o'clock position. Pulled off the road and let it cool down before continuing again. Again temp gage went waaaaaay up. Radiator is full with recommended coolant. Temp goes up at lower rpms at highway speeds though not that far. With higher revs in lower gear the temp is now staying around 210.

I'm thinking the water pump is not working well. Any other suggestions from the great and knowledgable venture riders would be greatly appreciated.

Doug

I know you have a gauge on it but did the engine overheat light come on? The light is located in the lower right hand corner of the right panel on the fairing. If your light wasn't on I doubt if you were overheating. Did the engine feel hotter than normal? Your gauge may be malfunctioning. Sensor for gauge may be siting in air instead of antifreeze. Did you service cooling system recently?

The temp light never came on. The cooling fan did cycle several times. I've owned this bike since 2008 and when I first got it the fan rarely came on. Now it seems to come on more often. I did have the valves checked middle of last year and the dealer said they flushed and replaced the coolant. The coolant is red like the stock coolant from yahama. The thing that concerns me the most is the way the temp goes up while crusing at 70 to 75 in 5th gear. And it goes up at lower rpms. I did have to replace the gage once before and I noticed that the new one did consistently read a little higher than I remember the old one. I checked with an infrared thermometer in the past and it showed about a 20 degree lower temp than the gage was indicating. I've just never had it go so high before. 61000 miles on the odo.

I couldn't really feel any excessive heat on my legs while riding. It was a little hard to start after I pulled off the road to let it cool down. After getting off the interstate and heading home I had to stop for gas and it started right up after fueling.

Thank you,

Doug,

Maybe change the thermostat? Maybe even use a lower temp thermostat?

Couple things would be thermostat. Next would be to make sure it is flowing once thermostat opens. I would have to do a little looking but some systems require bleeding because the fill port is lower than system basicly.

Did your Cooling Fan run ?

After much searching I have been unable to locate anything on what might be causing my 2005 midnight to run hot today. Went for a ride with two friends (on Harleys) today and got into stop and go traffic on a side trip to Ocala. The temp gage (Sunpro small triple set) started going up and up and up till it was pointed at the six o'clock position. Pulled off the road and let it cool down before continuing again. Again temp gage went waaaaaay up. Radiator is full with recommended coolant. Temp goes up at lower rpms at highway speeds though not that far. With higher revs in lower gear the temp is now staying around 210.

 

I'm thinking the water pump is not working well. Any other suggestions from the great and knowledgable venture riders would be greatly appreciated.

 

Doug

Did your Cooling Fan run ?

The temp light never came on. The cooling fan did cycle several times. I've owned this bike since 2008 and when I first got it the fan rarely came on. Now it seems to come on more often. I did have the valves checked middle of last year and the dealer said they flushed and replaced the coolant. The coolant is red like the stock coolant from yahama. The thing that concerns me the most is the way the temp goes up while crusing at 70 to 75 in 5th gear. And it goes up at lower rpms. I did have to replace the gage once before and I noticed that the new one did consistently read a little higher than I remember the old one. I checked with an infrared thermometer in the past and it showed about a 20 degree lower temp than the gage was indicating. I've just never had it go so high before. 61000 miles on the odo.

 

I couldn't really feel any excessive heat on my legs while riding. It was a little hard to start after I pulled off the road to let it cool down. After getting off the interstate and heading home I had to stop for gas and it started right up after fueling.

 

Thank you,

 

Doug,

Since the hot light never came on, and the cooling fan was cycling on and off, it sounds like the bike was just fine. Put the temp probe of your temp gauge into boiling water (Distilled if you have it). It should read 212°F or 100°C.

Because the cooling fan cycled several times and I never really felt excessive heat coming from the engine, I began to suspect the gage. I decided to try a replacement. I removed the old Sunpro gage set and replaced them with equis gages from Autozone. I don't know if they're of any better quality but they appeared to be. The mounting system for the new gages was completely different from the old and I had to re-do the mounting bracket. After much working and re-working the bracket I got the new gages mounted. I got them all plumbed and the bike buttoned up last Monday afternoon.

Took it for a short ride (about 6 miles) and the gage never got above 220F. I ran it at low rpms to see what would happen. Today I took it for a longer ride and again the temp never went above 220F. Never did get into stop and go traffic but I did ride at some slow speeds.

I'm thinking and hoping problem solved.

Thank you to all who offered suggestions. As many have said, this is a great site and great group of people.

Thanks again,

Doug