Trabi Thermodynamics! So, I've been driving about in Comrade Trabi for practically a year now, taking only a few weeks off to avoid road salt. I've become quite familiar with Trabant technology in the process. As most Trabant Comrades realize, a Trabi has no motor temperature monitoring system at all! Why not? Practically every other car on the road has either a warning light or gauge for motor temperature, so why not Trabants? Oh, you say, it's because those poor, starving comrades in Zwickau couldn't afford one! After all, they couldn't afford a fuel gauge either, right? No, I suspect the lack of temperature measurement is because it's not necessary. The fuel gauge isn't either, on a car with "reserve" fuel. Why wouldn't it be necessary? it is on every other car, so why not ours? I believe that it has to do with the way our humble 2-cycle motors operate. They run cold! First, our compression ratios are low. Less compression = less power = less heat Second, the hot, expanding combustion gasses are expelled from the motor very quickly compared to a 4-cycle motor. They start being expelled with the piston only 1/2 way down on the power stroke, while a 4-cycle motor holds them in for the entire power stroke and much of the exhaust stroke. Third, the crankcase is being cooled by the evaporative action of the carburetor vaporizing fuel. This can actually lead to problems with keeping the fuel vaporized long enough to still be combustible when it reached the combustion chamber! So, a lot of cooling fins and a fan are plenty to keep temperature under control on even the hottest days at full power. No need for a gauge! On cold days, keeping the crankcase warm is the issue. That's why the cooling shrouds direct the air past the cylinders and heads and DOWNWARDS past the crankcase. Just try to warm that big heavy crankshaft up when it's being "refrigerated" by the carburetor! It takes awhile, as the heat of combustion is far away and the roller bearings produce little heat. There's no circulating oil heated elsewhere to warm things up, either. The cold crankcase effect leads to fuel condensing in the crankcase and the motor getting very lean at a cold idle. When one speeds up, the condensed fuel/oil mix is blown into the cylinders suddenly causing a sudden, temporary over-rich condition with plenty of smoke. One really important thing to consider for those of us in damp climates: This cold crankcase effect will cause moisture condensation and subsequent corrosion of the crankshaft and bearings if the motor is not fully warmed up, especially if it is to be stored for any length of time. The good news is, 2-cycle oil usually has additives to retard moisture-related corrosion, so that will help some. Before putting your Trabi away, it's very important to have the motor just as warm as it will get and preferably on a dry day. So, as with any other car, short trips are bad! Any thoughts on this tricky and complex subject?