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Oil Temp. Gauge

badgertom

New member
Is it worth the cost ( about $ 120) to install an oil temperature gauge on a
1982 R65. Since the bike is air cool it seems to me that if riding in an area with lots of traffic / or stop and go traffic the engine temp. may be important to assure no problems. Yet, most "older" bikes do not seem to have an oil temp. gauge implying that the bike designes felt there is no need. (?).
 
imo- just something else to worry about.
if you're in stopped traffic, just shut the bike off until you're moving again. if in slow'ngo traffic, pull over to shut it off if you notice your legs or feet feeling abnormally hot.
 
In general, the Airhead engine doesn't need the extra cooling and adds a potential failure point in the oiling system. And depending on where the system is plugged in, it might just present you with information that only causes concern when there really is none. Being conscious of your situation when riding, you can avoid instances of no air flowing over the bike.

That said, if you feel that this would give you some peace of mind, it might be worth it.
 
I put an oil temperature gauge on my 82 R100RT. I found that the oil temperature would rarely if ever run hot even in stop and go traffice in Florida where I lived at the time. If, however I was pulling my Pod trailer, stop and go traffice would cause the temperature to rise rather quickly.
 
I've had one of those dipstick type gauges for years on several airheads. I only saw it rise to the danger point one time (R100RT), and that was in a parade that I was riding in. I am a Shriner and that parade lasted more than 30 minutes of moving at walking speed before it got too hot. I dropped out of the parade and let the bike cool.
 
Thanks for the info. I'm probably over cautious. Perhaps I'm just creating a problem where there is none.

Being cautious is good, When the bike begins to overheat you will often get strange odors & sluggish performance sometimes unfamiliar noises.

I'm not so sure that shutting down for brief periods & re-starting accomplishes much other than potentially running down your battery and wasting the life of your starting system. When a stock airhead battery runs down the minimal charging system takes quite a while if ever to bring the battery up to full charge.
 
I had one on my '77 R100S. It really was just sort of an "FYI" device to me. It's hot outside, I'm riding slow in traffic, watch the gauge go up. It's cool outside, I'm cruising along at 65, temp stays low.

On an airhead, you KNOW when it's getting warm. I get "rosy shins" in the summer when riding in hot weather, especially in slower traffic.

Seriously, if there's not an oil temp gauge on there now, save yourself the expense. Don't let your oil level get too low, if you're stopped on a hot day, say at a train crossing or something, power down for awhile.
 
Since the bike is air cool it seems to me that if riding in an area with lots of traffic / or stop and go traffic the engine temp. may be important to assure no problems.

This is another example of applying water cooled theory to aircooled motorcycles.

The fact is, engine heat for the airhead occurs in direct proportion to engine rpms, which of course is direct proportion to fuel burned.

In stop/go traffic there aren't any rpms and the engine runs cooler.

It's not a matter of reduced water and air flow through a radiator ... because the water pump and fan are turning slowly.

Those of us that have had airheads with factory oil coolers with thermostats know this--the only time oil circulates through the oil cooler is on long high speed highway runs where rpms are high and aero drag requires lots of power to overcome.

As always, if you're concerned about engine heat, run synthetic motor oil. Your '82 R65 already has Nikasil cylinders.
 
Actually heat generated by an airhead or any other internal combustion is not proportional to the rpm of the engine. An air head cruising at 40 mph on flat ground turns the same rpm as when going up a hill at 40 mph. The up hill run uses more fuel and generates more heat at the same rpm. The heat generated is proportional to the amount of work the engine is doing which is proportional to the amount of fuel used.
 
Is it worth the cost ( about $ 120) to install an oil temperature gauge on a
1982 R65. Since the bike is air cool it seems to me that if riding in an area with lots of traffic / or stop and go traffic the engine temp. may be important to assure no problems. Yet, most "older" bikes do not seem to have an oil temp. gauge implying that the bike designes felt there is no need. (?).

I fitted a temperature sensor and gauge to my oil-cooler thermostat equipped 1994 R100RT recently (VDO gauge $30, VDO sensor, which replaced engine oil drain plug, $25, instrument pod $25, plus wiring etc ). It is something I had wanted to do for some time as I was curious about how the bike holds up in my mix of urban, suburban, interstate and mountain rides (no off-road).

If oil temperature is a measure of how much the engine is stressed, then the most onerous duty I see is in stop/go commuting urban traffic.

My experience so far is with ambient temperatures in the 60 to 90-deg. F range. Here, provided I am moving between typical urban, mountain twisties, and ÔÇ£slightly elevatedÔÇØ interstate speeds, oil temperature sits around 180-deg F. It will creep up to, but not beyond, 205-deg-F in light traffic. In heavy stop/go traffic, say the 10-minutes it takes to travel the one mile and two four-way stop intersections in traffic as I enter my subdivision in the evening, or like this past weekend working slowly through the crowds and traffic in downtown Bryson City, NC, seeking respites from their onerous fall "leaf peeping", oil temperature will quickly hit 220-deg. F. Out of traffic it soon settles down again.

I have not yet experienced the effects of longer urban stop/go traffic, or the stop/go interstate jam/crawl in which I find myself when AtlantaÔÇÖs traffic snarls-up, but I know from when I have ridden the bike in this type of situation in the past it gets ÔÇ£unhappyÔÇØ ÔÇô so does itÔÇÖs rider. This is the real reason why I wanted to monitor oil temperatures.
 
Never had a problem with overheating the oil, considering the characteristics of modern formulations far exceeding anything the oils of the 70's contained. Near the end of a day's ride, just turn up the wick, the bike always responded, 5K or 6K never seemed to matter. '74900, no oil temp gauge, think autobahn. There' s always the winter for fixing whatever.
 
For me it is always nice to have another gadget I can watch while riding on long stretches of highways.

Did you know that a strong headwind lowers the oil temperature while with tailwind the engine runs hotter? That needs plenty of time to think about "WHY?". Beats counting cows on pastures flying by. ;)

/Guenther
 
For me, just leanin over a bit and resting my hand on a valve cover tells the whole story. Why complicate what isnt? LOL........One could always get an infrared temp sensor and shoot it while riding along or sitting in traffic.........I get a kick out of the doobers who pull theirs out and check out their RV wheel bearings every gas stop.......lol....to each his own.....My old Airstream or R/90 just keep on rolling........God bless.......Dennis
 
Actually heat generated by an airhead or any other internal combustion is not proportional to the rpm of the engine. An air head cruising at 40 mph on flat ground turns the same rpm as when going up a hill at 40 mph. The up hill run uses more fuel and generates more heat at the same rpm. The heat generated is proportional to the amount of work the engine is doing which is proportional to the amount of fuel used.

This is accurate and I touched on it noting high speed aero drag.

To go up the hill at 40 mph requires either more rpm (a shift down) or more throttle to maintain the same rpm not shifting, either of which indeed uses more fuel to do the increased work. The work's the same, so either method is likely to require nearly the same fuel and generate the same heat. This affected, of course by pumping losses caused by a more-closed throttle, i.e. economy could be better simply with the larger throttle opening as opposed to the downshift.

In any event, blipping the throttle while stopped in traffic does nothing but put more heat into the engine and engine heat in traffic is not the problem
 
The original question was basically, ÔÇ£Is it worth the cost.....to install an oil temperature gauge.....to assure no problemsÔÇØ. The basic functional answer is probably that knowing the oil temperature is not going to assure there are no problems. There will be many more, and more obvious, telltale signs of impending doom/gloom before anything that a nuance such as a change in oil temperature may indicate. Much more practical for an airhead is having some indication of battery/charging condition ÔÇô voltmeter is easy to install, an ammeter is probably more valuable but is a little more tricky to install. Next, maybe knowing oil pressure, as an indicator of impending mechanical doom, might have value.

I choose to monitor oil temperature because thatÔÇÖs my area of interest. Each to their own.
 
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