Heat issue

[GeoAggie]

I've owned 3 ST's from '03 to '07 to '12. All ran hot even though the '12 model is noticeably cooler in stock form. In every case I removed the inner fairing panels and then zip tied the fairing and thermostat. That made the biggest difference every time. Next in importance was adding the Honda fairing extenders. In 2012 Honda plugged some of the holes between fairing pieces and the frame and I've noticed this also reduces heat flowing on the rider's legs. So, I only removed the fairing pieces on my 2012 and it completely solved the heat issues during south Texas rides.

 

[Chris09]

I'm about to start riding my ST again after I cancelled the insurance for close to a couple of months, I'm particularly interested in this post, seems like a variety of different experiences with heat on basically the same motorcycle. I've got zero experience with anything over 25C / 77F with this bike and during this current record heat on the lower mainland I'd rather just sit it out, cooler weather is coming... isn't it?
What comes to mind overall is something I heard about I think it was Ford [and I like Ford] with one of their instruments, it was biased in some way, such that provided the measured variable fell within some acceptable range, it would display a constant needle position that had been selected by their psychology department deemed least likely to provoke inquiry by the owners.
Either BS - Ford would never do that, so Honda would never watch what happens to Ford for doing it, then copy it, or I've just got to cancel my subscription to The National Enquirer and Alien Weekly.
There's obviously a lot of variables concerning how hot a person is gonna get, you've got heat conducting, radiating and hot air with different humidity values impinging against you and so on.
It seems that more or less under just about all accounts I've heard so far, a well running 13 will achieve three bars and maintain that display until the tires melt.
I mean, there's gotta be some real variation in cooling system heat transfer going on between all these bikes; I mean doesn't anyone with a somewhat neglected cooling system and dirty radiator ever get to four bars?
I think by now I saw a 13 thermostat and aside from a min flow orifice [I think.. maybe? ... different thermostat?] it's a conventional type that will modulate through it's gradient through likely a narrow temperature range, so at extreme temperatures one of two things are happening; the thermostat is modulating close to wide open but remains within the gradient, or it reaches the full extent of travel. If it achieves wide open there's no more regulation so now coolant temperature becomes a function of how much heat your rad dumps and how much your aluminum alloy assembly can otherwise ditch.
I guess it's possible that the cooling system is that robust that yeah, between the pump and the stat it's always in control - built for death valley [or is that Lyton now?].
I'm wondering if anyone has actually monitored the temperature close to the thermostat under severe conditions and can actually verify a correlation between temperature leaving and three bars, or if the fourth bar doesn't come on until some - too late, sucks to be you - temperature.

 

[Bmacleod]

I put more stock in ways of modifying airflow than trying to modify the engine. The fact is the engine temp is regulated and the rider is sitting behind it... simple thermal laws. IF you could do anything to create less engine heat, the t-stat will still keep the engine at 180 degrees. The only 2 things I have found to POSSIBLY make a difference, in my case was the rubber mat that sits under the throttle bodies got bunched up behind the engine one time when I had it removed and didnt get it placed properly on reinstallation. My thought was that it was stopping hot engine air from escaping out the bottom of the bike. After that bout of winter maintenance, I thought the bike seemed hotter than normal. After straightening out the mat, it SEEMED better, but like all talk on this subject there is no data to confirm anything... it is all seat of the pants. I have removed my inner fairings and from a simple airflow perspective it SHOULD make a difference, but I am not convinced. Again, just seat of the pants. One thing I have noticed is that when riding around town, my fans come on much more and sooner when I stop at traffic lights. My thinking is that the inner fairings "funnel" the air through the rad. My feeling is the engine is high and wide and almost completely contained within bodywork. Anything you can do to get that air out, should help, but your options are really limited.
The best way to reduce the heat is to keep moving

 

[Chris09]

I missed the dduelin [top post] before opening my yak, I did not know that, thanks for that information!

 

[Andrew Shadow]

I'm wondering if anyone has actually monitored the temperature close to the thermostat under severe conditions and can actually verify a correlation between temperature leaving and three bars, or if the fourth bar doesn't come on until some - too late, sucks to be you - temperature.

Third bar of the temperature gauge illuminates at 150° F, 65.6° C.
The fourth bar illuminates at 230° F, 110° C.

That allows a wide temperature variation of 80°F, 26.7° C, during which the third bar is illuminated. As different engines of the same type will not all run at exactly the same temperature under the same conditions due to many factors, this rather wide range of 80° F, 26.7° C, could account for the reason why some people find that their engines run very hot and others don't. It might depend on where in that 80°F, 26.7° C range your engine is operating.

 

[Bmacleod]

Third bar of the temperature gauge illuminates at 150° F, 65.6° C.
The fourth bar illuminates at 230° F, 110° C.

That allows a wide temperature variation of 80°F, 26.7° C, during which the third bar is illuminated. As different engines of the same type will not all run at exactly the same temperature under the same conditions due to many factors, this rather wide range of 80° F, 26.7° C, could account for the reason why some people find that their engines run very hot and others don't. It might depend on where in that 80°F, 26.7° C range your engine is operating.

Good point

 

[Chris09]

Thanks Andrew and I guess on the flip side of that, I wonder when you bolt out into the 39F or colder air after you warmed it up to 3 bars, how cold does your water leaving get until (if ever) it drops down to 2 bars? I think Ill be strapping a thermister somewhere when I open it all up in october, thats too wide a span to not know how hot you are, especialy when other ____ starts going sideways

 

[Andrew Shadow]

...... I wonder when you bolt out into the 39F or colder air after you warmed it up to 3 bars, how cold does your water leaving get until (if ever) it drops down to 2 bars?

I doubt that you would ever see two bars unless you have a defect somewhere in the system. The temperature gauge is fed by a sensor that is on the engine side of the thermostat. Once the engine has reached full operating temperature, regardless of ambient air temperature, the engine will remain at the temperature that the thermostat is designed to keep it at. The most that will happen, if it is extremely cold, is that the cycle time between when the thermostat closes and then re-opens will be greater. This is because the coolant entering the engine is colder and therefore takes a little longer to warm back up to the temperature where the thermostat opens again.

You can see these fluctuations in very cold weather on vehicles with needle temperature gauges. The needle will drop further in to the cold side of the gauge than it normally does every time that the thermostat opens. I doubt that you would ever see a difference with the ST1300 temperature gauge for two reasons;
1- because the third bar covers such a wide temperature range, to wide for it change the number of bars being displayed due to these conditions.
2- I doubt that you would ever be riding in weather cold enough to achieve this. I have ridden in temperatures well below freezing, and always three bars showing.

 

[red one]

I think it was last year or maybe the year before I posted under ST sightings a blue ST1300 who's rider was wearing shorts in town here in stop and go riding fwiw.

 

[Chris09]

Yeah no I get all that but I wonder if you could get a situation where your thermostat fails to fully close or modulate down smoothly, meanwhile you're staring at three [worse than useless] bars while your computer [unbeknownst to the rider] is compensating for a real analogue value [which should have just referenced to a gauge].

 

[red one]

Yeah no I get all that but I wonder if you could get a situation where your thermostat fails to fully close or modulate down smoothly, meanwhile you're staring at three [worse than useless] bars while your computer [unbeknownst to the rider] is compensating for a real analogue value [which should have just referenced to a gauge].

I have a ST1100 and not an ST1300 but when my bike was having trouble with the temp one time my thermostat plunger was rubbing on the mounting points. I could see where it was rubbing so maybe it caused it to have wild temperature swings. Replaced it and it cleared up. That was about 10 years ago. About 4 years ago I was having heating problems and through trail and errors solved it mostly. On your ST1300's I'm surprised it would not throw an error code if the computer does not detect the right operating temperature.

 

[Andrew Shadow]

Yeah no I get all that but I wonder if you could get a situation where your thermostat fails to fully close or modulate down smoothly, meanwhile you're staring at three [worse than useless] bars while your computer [unbeknownst to the rider] is compensating for a real analogue value [which should have just referenced to a gauge].

The most common ST1300 thermostat failure, as in almost always, is in the open position. That is when you will see the temperature gauge bouncing back and forth between two and three bars. Unless the thermostat is sticking enough to cause a big enough engine temperature drop for the gauge to go down to two bars, there isn't much to be concerned about.

On your ST1300's I'm surprised it would not throw an error code if the computer does not detect the right operating temperature.

It will throw a code if it detects a value in the engine coolant temperature sensing system that is out of parameters. That is more reflective of a problem with the sensor system and/or associated wiring.

As far as detecting when the engine is operating out of the correct temperature range when there are no faults in the sensing system, that is the job of the computer holding on to the handlebars who is supposed to be regularly checking the temperature gauge whenever the engine is running.

 

[Slammer]

You should have tried the BMW LT 1100, aka "Eierkocher" translates as "Egg cooker," go figure.

 

[MarkBlake1300]

I have a 2016 st1300pa, It's been hot here in the upper 90's, the heat from the engine has gotten so hot it's unbearable at times.
Any thoughts on how to lessen the heat that is generated.

Thanks
Kevkev

check this out

 

[Chris09]

Thats a great point ill keep in mind Ryan - hotter makes cooler and why.
Riding in the mid 90s - too hot for me but come Oct when I tear it apart Ill figure away to at least deflect heat away better
caught up with my new best friend Al we went for a rip out to Sasquatch Inn (40miles from Coquitlam?) Im gonna say 84F, some smoke cloud cover, his is a low (low) miler ST13 04(?) mines an 09, 35k, Id have to say power , sound, radiant temp of both bikes the same, Im in jeans, asiac runners with thin mesh, hes in some kind of ridding boot jeans, we were hammering them pretty good; he can ride, I can catch up (sort of) were a bit over 80 mph, were both about the same opinion - annoying heat left side both bikes running smooth as silk, but that heat has got to go

 

[Sadlsor]

If it weren't for bad luck, I'd have no luck at all.
Reading these heat issue threads, sometimes makes me wonder why I don't have one. It's so out of the norm for me, and it's not my style, to "get lucky".
But then I quit wondering, accept my fate, and go ride the p!$$ out of it. With joy, and with a stupid big grin on my face.
It's hot as hell in Alabama this summer.
But my 2008 is super-cool.
Come visit.

 

[Kevcules]

check this out

I happened on that same video yesterday. Very interesting.
I'm not interested in more noise from the exhaust, but if it reduces the heat. Hmmmm.......

 

[dduelin]

If it weren't for bad luck, I'd have no luck at all.
Reading these heat issue threads, sometimes makes me wonder why I don't have one. It's so out of the norm for me, and it's not my style, to "get lucky".
But then I quit wondering, accept my fate, and go ride the p!$$ out of it. With joy, and with a stupid big grin on my face.
It's hot as hell in Alabama this summer.
But my 2008 is super-cool.
Come visit.

Don't feel left out. You live in a place that is hot and humid much of the year. Many of the heat complaints come from our northern friends that are not as used to the heat and humidity as those of us in the deep south. If some ST13s are hotter than others I always felt mine wasn't in the hot group and it's heat never bothered me or stopped me from riding my ST at any time to any place.

 

[Byron]

Another way to drop the felt heat is to keep it inside the exhaust pipes, ceramic coat your pipes. Not only does the ceramic coating keep more heat inside the pipe to have it exit out the muffler but it also keeps the pipes looking better longer.

 

[Sadlsor]

But what is that increase in trapped and confined heat (there's that redundancy factor again!) doing to the muffler internals?
I bet it's up to no good in there!