GS-Riders International

Dear GS-Lovers,

since this forum has very often given me useful information and provided excellent technical information, I thought the following might be interesting to you:

I recently decided to invest in a new toy and bought an oil temperature gauge for my R1200 GS 2008. It constists of an analog display, mounted near the cockpit panel, and a temperature sensor which replaces the oil bleed screw.

It is interesting to compare this new information with the oil temperature indicated in the cockpit (the tiny bars on the right):

- During warming up of the engine, the cockpit shows relatively fast three bars and stays then constant on three bars when the bike is in normal use (no extrem temperatures, engine with low or medium load, no stop-and-go). The temperature gauge takes much longer (app. twice the time) to reach a temperature at app. 85 °C; it then stays constant (+/- 5°C when the oil cooler valve opens). Fazit: So far, so good. Everything seems to work ok.

- In the mountains (French Vosges, small, winding roads) with speed of app. 40 km/h (medium) and the engine heavily loaded (fast accelerations, high revs), the temperature increases until 120°C. The display shows one bar below max. Both remain constant and do not seem to rise further.

- On the German Autobahn with revs between 6.000 and 8.000 U/min and outside temperature at app. 30°C, the engine gets hotter and hotter. After one hour of continuously driving with a heavyly loaded engine (yeah!), the gouge showed more than 130°C and seemed to rise further. The cockpit display showed 4 bars and remained constant for the whole ride.

- In stop-and-go traffic, the temperature seems to rise without limits. After 20 minutes it shows more that 150°C while the display remains one bar below maxium. Hmmm.

- When the bike is parked and the engine is killed, the displayed temperature does not rise (=> no influence of the hot exhaust on the sensor?).

Now I am asking myself:

a) What is the best position for an additional temperature sensor and how can it be easily mounted?

b) Does the temperature in the oil sink make any sense and does it provide any usable value?


c) The information given in the cockpit does not seem to be linear. Even when the measured temperature in the sink is extremely high, the indicated bars stay below maximum. Does the board computer somehow interprete the measured values? Where is the original sensor?

d) Most interesting: Is it possible to overheat the engine in extreme conditions? Are the indicated bars a reliable information?

Any ideas?

Thank you all and greetings from Germany

Alex

Dear Peter,

thank you for your staments. I indeed agree that these gauges easily could become a problem for the driver, not for the engine.

As far as Stop-and-Go is concerned: Of course it is always a good advise to cool the engine down by driving. But what is better when you can't do that, means from what point is it better to kill the engine than to continue idling? Probably nobody is happy when he watches his oil flowing on the street through the melted oil show glass ...

It would be interesting if somebody has managed to overheat the engine, means that the displayed bars are beyond the limit. In what circumstances did that happen? Stop-and-Go? Full throttle for a long time?

Greetings!

Alex

Yes, this temperature issue is interesting. It is easy to say "don't kill the engine but drive a little bit", but when you get really stuck in traffic (as you probably know), at least here in Germany, you have absolutely no chance to cool the engine by riding.


I wish you lots of fun in Garmisch! When you go there, try keeping her for more than 90 minutes at over 7.000 revs and then tell us what has happened...

Alex

No, not in the middle of the day, too much traffic. But when I returned from France last weekend and had to go all the way north to Hamburg, there were plenty of opportunities. Sunday morning with little traffic.

Of course, in normal conditions driving that fast is not possible. I belong to that group of people that say that especially on the heavily crowded Autobahn, driving permanently on the left lane, with sufficient safety distance, is more safe than driving in the middle or on the right because you do not have to change the lanes so often which is one of the main reasons for accidents.

What about Montana? Someone told me the this US state has no speed limit anymore (driving "reasonable and prudent").


Regards


Alex

I agree, the engine sounds different when it's run hot. I switch the engine off when last allowable bar is reached. I have no doubt that this will not damage the engine.

Theoretically, I think as long as you stay below the limit, everything is fine and you can keep the engine running as long as you want. It would be interesting if anyone has managed to get the engine overheated (more bars than allowed). In what circumstances can that happen?

- going at high revs in hot wheather? (no, not from my experience)
- idling for a long time? (probably)
- Stop-and-go?

AFAIK, I read once in a German forum that the reason, why the Berlin Police department decided to purchase Moto Guzzis instead of BMWs was that BMW could not guarantee idling engines for more than 30 minutes. Don't know if that's really true.