Maybe you should buy Chris Scott's book it tells you all about it in his book and says water cooling is superior.
You aren't supposed to need one if riding above the tropic of cancer , however you are riding through North America , central America and South America. I don't need one as I finish in Vladivostok (I have same bike as you).
Perhaps you ought to fit an oil cooler to your bike? , you can find them on ebay for £15. While you are riding through Russia you can cover it to prevent it from overcooling your engine, an oil cooler will also increase slightly the oil capacity giving a bigger heat sink.
The XT600E has a bit of a pants design though in that the oil tank is in the head stock which melts the bearing grease which causes accelerated wear.
What damage happens when the engine overheats?
It will likely cut out and as an extreme possibly seize the piston in the barrel causing you no end of grief. Or possibly warp the valves , but don't worry the XT600E engine is the old lump based on the Tenere and those engines will run (albeit poorly) with damaged valves and even badly worn rings.
Terra circa apparently overheated one of their DR350s and it needed engine out in Russia. But when they first went round in Mondo Enduro their bikes were fine and didn't make any mention of an oil cooler.
Will a dipstick temp gauge actually be of use preventing that?
Maybe in that it'll give you a bit of a warning before it gets too high giving you the ability to cool it down before it starts to get too hot. But there are warning signs ie the bike will start to run poorly and due to convection you will start to cool on the bike.
Or just try not to get stuck in heavy traffic ie leave town very very early in the morning , and arrive late after the typical rush hours.
If it gets too hot, is simply switching off the right thing to do?
Maybe.... in that as said above once you turn it off the oil stops circulating for the XT600 that means the tiny amount of oil going round the engine has to vent its heat to the engine which the engine vents the heat to the air , if you keep the engine on with the bike facing the wind it circulates oil to the sump near the head stock giving more surface area to cool down. I would probably ride fast to cool it down , or if stuck in traffic fight a side road somewhere to ride up and down to cool it THEN give it a rest.
What temp constitutes "too hot"?
Depends on the oil mineral oil will decompose and break down into its elemental strings at over 115c, full synth which my XT has decomposes at 125c , since the red line on my CBR is 100C , I would hazard a guess at 95-110C being the red line. My CBR in Spain constantly had the fan on the radiator but only when stuck in traffic and consequently I avoided traffic instead. This is probably why on aircooled bikes you are supposed to change the oil a bit more frequently.
When it gets too hot, will there be other warning signs or is the damage done by the time they appear?
Oh yeah the bike will run poorly , and the bike may die suddenly for no good reason due to vapour lock (where fuel is heated inside the fuel filter that it causes an over pressure inside which blocks the flow of fuel to the carb), it you get vapour lock stop push the bike and let it cool off.
Is a dipstick gauge actually just a distraction that I won't be able to see or will forget to look at or will look at when I should be looking at the road?
It will only overheat if you are stuck in traffic for a long time as long as there is airflow and you are not riding through the Danikil where there is a phenomia called the fire wind (which varies from 40-57C) there will be a temperature differential which will in theory cool the bike.
Last edited by Kennichi; 23 Mar 2009 at 23:08.