"Normal" coolent temp on a R1250R? "Overheating a wethead"?

On my old airhead(99' R1100R), once I started it, put on my helmet, gloves and jacket, it was perfectly warmed up and ready to ride off. I was ALWAYS cautioned NEVER to leave an airhead to idle for more than a few minutes as you could overheat it.
Fast forward to my 2020 R1250R, water-cooled with a radiator. Question is two fold. One, what's the normal water coolant temp? The TFT has shown it as high as 215 deg, radiator seems to kick in at about 205 deg. Second, is it safe to let a wet head idle for a bit longer as it's water cooled?

Thanks in advance.

The wet-heads (1200) should run around 180- 185F under normal riding conditions. We (brother and I) haven't seen anything higher than 194F on any of the 4 bikes we have had.. YMMV There is very little difference between the 1200 and 1250 BTW..

On my 2015 GSA, and a friends 2020 (I think) 1250RT, the fan switches on at about 212 degrees, and drops the temp by about 10 degrees, before switching off. When in motion, at speed, my GSA generally runs at about 180-185 degrees.

When my 1250r was brand new it ran what I thought was worryingly hot but it seemed to settle down after the motor was broken in. Not sure if thermostat was sticky or what but no issues since. Also maybe an air bubble from the factory? But agree with above its normally pretty steady around 185F unless stopped at a light during traffic and then it goes up till the fan kicks on.

coachz said:

When my 1250r was brand new it ran what I thought was worryingly hot but it seemed to settle down after the motor was broken in. Not sure if thermostat was sticky or what but no issues since. Also maybe an air bubble from the factory? But agree with above its normally pretty steady around 185F unless stopped at a light during traffic and then it goes up till the fan kicks on.

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That seems similar to my R1200 GS. it's in the mid 180's while moving, but once I'm at stop lights or stop & go traffic it can be in the 200-212 range.

A lot depends on the ambient air temperatures where you live, however the radiator fan should cycle on and off as needed while idling.
I do a lot of commuting on a 2016 GS ADV and a 2021 R1250RT and over 200 is not abnormal in slow traffic with the fan cycling periodically.

If you live where temperatures are frequently over 100-degrees F then you'll see that more often and temp while riding will be higher than the 185 or so others have mentioned.

Overall i would not be concerned unless I saw continuous temps over 212 or higher.
Also make sure coolant levels are good in the overflow bottle, as it gets hotter and coolant expands it will go into the bottle, then when the motor cools it will draw it back in from the bottle.
However if you had air in the system and the overflow bottle is empty it can't "self-refill"

Also my 2016 had some mild "weeping" from the hole on the left side of motor case until the water pump seal seated fully - it seemed to be common on those bikes.
I just kept a closer eye on coolant levels and took a 0.5L bottle of it with me on a long trip just in case but never needed it. Now coolant checks are done regularly just like oil level and tire checks!!

I live in one of the hottest places in the US where our summer temps are generally over 110 degrees. My home is actually below sea level so our temps are usually within one or two degrees of Death Valley temps.

My R1250RS has not overheated at any time in those temps and is one of the cooler to ride bikes I have owned. My old '01 R1150GS ran fine in the temps but I did see some nasty overheating in Acapulco in a late afternoon traffic jam where the fan on the little oil cooler just could not keep up. I do not see that problem to ever be an issue with the liquid cooled engines.

This thread is a good example of how BMW's recent decision to discontinue the provision of service information puts BMW owners wishing to understand and address service issues with their machines at a disadvantage.

By way of illustration BMW previously made available the thermostat opening temperature, the fan turn on temperature and the high temperature warning point for the F800GS and F650GS motorcycles.

My currently updated REPROM for my '16 R1200RT (0A13 - USA) has this to say in Section 17 - Cooling:

Cut-in temperature for coolant temperature warning: 118 C (244.4 F)
Cut-in temperature for radiator fan 105 C (221 F)

This same type of worry always show up in my S1000RR forums too, where people think anything even near boiling (212 F) is dangerous.
Heck, it's a pressurized system with two radiators and if BMW says that's what it's designed for, believe 'em. I've never had my coolant "indicator bar graph" show more than mid-level even in Death Valley, and I think it's a shame they put the actual degrees on the new TFTs because guys just aren't used to seeing those in relationship to design. It's like the OK checkmark for oil level. Good enough for most.

Re question #2 -- there is no reason to let these engine idle for more than a minute -- as long as you aren't on a track day and giving it full throttle immediately. We used to warm them up to be kind to the engine (modern oil and metallurgy have obviated that) and to be sure it didn't stall as we pulled into traffic (FI takes care of that).