How Hot is Hot?

[michael816]

I was wondering how hot should a GS1100E run? I noticed it getting around 320F while driving on the freeway. I was thinking about installing an oil cooler. Should I worry about this?

[Cassius086]

I would have a freaking stroke if my bike got to 320*...I have a derale cooler, and even on the hottest days, I never see above 210* unless I have to slow down or stop for a time. I run synth M1 15w50. Your temp should drop as you start moving, especially if you are on the freeway.

[Red Rocket GS1100]

Mine does too

Mine gets hot like that during especially longer rides. I almost die at every long light. I find that it wants to be at 210 but then starts climbing as the ride gets longer. Highway speeds dont help. I have suspected that I am running too lean. I plan to take it to my buddy who can tune the carbs for me. I dont want to put a sight hole in my pistons.

[Mark whiz]

If 320 is your oil temperature - that is WAY too hot.:shock:

Optimum oil temperature is considered to be between 160f to 210f. Below that, it doesn't flow as well and above that it begins to burn and carbon up. Synthetics give greater protection against the high temperature breakdown - but I think 320f would be pushing even their abilities.

I think it would be in your best interest to check out if your gauge is working properly. In the past I put a little stick-on thermometer on the head and it always read within 20f of what my oil gauge read - that might be a quick (cheap) little check for you to try.

[schinae]

If 320 is your oil temperature - that is WAY too hot.:shock:

Optimum oil temperature is considered to be between 160f to 210f. Below that, it doesn't flow as well and above that it begins to burn and carbon up. Synthetics give greater protection against the high temperature breakdown - but I think 320f would be pushing even their abilities.

I think it would be in your best interest to check out if your gauge is working properly. In the past I put a little stick-on thermometer on the head and it always read within 20f of what my oil gauge read - that might be a quick (cheap) little check for you to try.

You can definately run over 210... 210 is just where water evaporates from the oil. I would say if you start getting 245 and up you should be worried. My big bore bike can get up to 280 or so if you get stuck sitting in traffic before the oil cooler..

[michael816]

I just changed my oil (about 100 miles ago) do you think there is any breakdown of it? Should I change it again?
Should I install an oil cooler?
I have been meaning to sync and tune the carbs, I suspect they really need it. Do you think that will help?

Once I got home after seeing that I just parked it in the lawn and turned on the hose. I know that when the needle is near the top end of the gauge it is bad but I didn't know it was that bad.

Thanks for the help, great site by the way!!

[michael816]

Also if I do have to change my oil (it wasn't synthetic, it was the cheapest available) should I go with something other than 10w-40?

I know this has been asked a million times before but one more wouldn't hurt.

[tfb]

Check your jetting first -- no point in installing an oil cooler if she's running too hot to start with.

You may have leaking inlet manifolds -- which will cause lean running too.

[Mark whiz]

With only 100 miles on that oil, I wouldn't worry about it being degraded, yet. I know all too well how hot those Texas summers get, so going with a 15W/50 or 20W/50 might not be a bad idea - that's what I usually ran in my bikes when I still lived there. You can always change back to a 10W/40 for the "winter" months. A switch to synthetic oils is never a bad idea, at least in my mind. It's almost impossible for a normal piston engine to tear down a true synthetic (since they were designed for turbine engines running rpms in the 10's of 1000's range), but a bike does put a lot more stress on its oil than a car ever will.

BTW I would think twice about hosing down a really hot engine with water, dosing hot metals like that can cause cracking or warping issues. A better choice would be a big fan blowing directly across the engine.

[Dave8338]

I was wondering how hot should a GS1100E run? I noticed it getting around 320F while driving on the freeway. I was thinking about installing an oil cooler. Should I worry about this?

What color are your header pipes (the first foot)? :shock: 320F is TOO hot, yes temps rise as outside temps rise, but if you're looking at 320F, you have additional issues to deal with...you must be running lean, as was mentioned!

[bonanzadave]

At 90 degrees and high humidity its tough to keep the oil cool in traffic. I had mine pegged once. I believe someone posted oil specs here and if I remember right 10w40 will go to 400 degrees. Yesterday my little gizmo temp gauge read 105. On a hot day oil temps at 320 are OK by me. Makes me wish for the days when I took this picture....Burrrrrrr !!




Im with Mark on your water hose idea. Dont ever do that...

[AOD]

Took me a while to find this, because I don't have my report info in front of me from when I did a synthetic vs. conventional oil report in college.

Copied from http://www.synlube.com/oilv.htm#Cool

Because only about 60 percent of the engine cooling is handled by the radiator and coolant, the other 40 percent (more in an air-cooled engine) must be taken care of by the engine oil. The combustion process takes place at about 2000°F to 3000°F, which can heat pistons and valves to 1000°F in extreme cases. In pistons, much of this heat travels down the connecting rods and affects the bearings. Since tin and lead, two common bearing materials, soften drastically around 350°F and melt at 450°F and 620°F (respectively), it is important for the oil to transfer excess heat away from the bearings as quickly as possible. In valves, the long, thin valve stem is more easily stretched when hot as the valve spring pulls the valve tight against the seat. Too much stretch, and valve clearances disappear and valves and seats burn.

Petroleum Oil:

"Normal"

Conventional Petroleum Oils do not conduct heat too well, and actually most of the increase in oil temperature can be attributed to internal friction in the oil itself as the bulk oil temperature will rise rapidly with engine speed much faster than with engine load. Typical Motor Oil running temperature is about 20°F higher than the coolant temperature. It is however possible to have oil sump temperature in excess of 300°F even when the coolant is in 220°F to 240°F range. In many Air-cooled engines and especially the very small ones used in generators and lawn equipment it is not unusual to see oil temperatures approaching 400°F.

Conventional Petroleum oil deteriorates rapidly at temperatures over 260°F and at 320°F its useful life is only about two hours !

From http://www.synlube.com/oil.htm:

Synthetic Oil:

What is it ?

Synthetic oils are produced either by a chemical reaction (synthesis), severe refining or other complex chemical processes, that yield molecular uniformity and purity that is impossible to achieve through normal refining process.

Enhanced high temperature durability, reducing oxidation rates and wear on some engine parts because many synthetic will tolerate temperatures up to 400°F.

I have a great chart at home that has a side-by-side comparison of conventional vs. synthetic that shows you are okay running 320F+ with synthetic. I found a similiar chart though:

http://www.synthetic-motor-oil-change-and-filters.com/amsoil_articles/mineral-petrolium-oil-compared-to-synthetic/

It's interesting to see though, that TODAY's oil can breakdown quickly at temps over 270F ----- yet in 1983 there was no synthetic oil and these GS engines ran fine on conventional at temps well up to 270F...without oil coolers.

Even if you stick with synthetic oil and no oil cooler...today's oil far excedes 1980's oil and you're engine will most likely be fine!

~Adam

[AOD]

Bump - did I silence everyone?

[tconroy]

I know someone with the same bike and his reads the same.It says 320while riding but it isnt realy that hot.Maybe there is a problem with the calibration of the gauges on those.Does it "tick like a time bomb" when you turn it off or start running bad at that temp?You can get digital thermometers at harbor freight pretty cheap.I would not believe the gauge unless you have seen it different in the past.

[Clone]

:shock: My bike takes forever to get to 100C=212F and it only does that if I am sitting in traffic for a real long time. On really hot days on the highway, 35C, the bike will eventually hit 100C and then stay there, not get any hotter. Check your plugs, and see if you are lean. Your bike is in the danger zone with temps that high on the highway. I would even bet your pistons are covered with burned oil. And that if you pull the crankcase vent tube from the airbox when it is that hot you will get a steady stream on blue smoke coming out of it.