Acceptable Engine Temps when Climbing Mountains

[devitotl]

I took a ride on my 2003 ST1300a this morning from my house at 6000 ft elevation, down to the valley at 4500 ft elevation, up to a mountain peak at 9000 ft elevation, back to the valley, and then home again. Outside temperatures started in the 70s at my house, 80s in the valley, and mid 60s at the mountain top. During the ride down to the valley, my engine temperature gauge showed 3 blocks out of 6 total. It went to 4 blocks waiting for a traffic light in the valley. As I climbed up to the 9000 ft peak, it fluctuated between 4 and 5 blocks. It dropped to 3 again heading down the mountain on my way back, and was 4 again in the valley. On the final run up the hill to my house, the outside temperature increased to 90 degrees. The engine temperature stayed at 4 blocks until the last 5 miles of uphill twisties where I rode more aggressively and the temperature gauge stayed at 5 blocks for most of the uphill. Are these temperatures reasonable? I rode the same ride in the opposite direction a few weeks ago and was at 5 blocks for almost all of the uphill sections. I thought that was high, so I checked my coolant level when I got home and found it was low. I added coolant before today's ride. I'm wondering if low coolant was my only problem or if I need to look for more cooling issues. Thanks for any insight you can offer.

 

[drrod]

Low coolant may have been the only issue but to be safe I would say your cooling system needs to be checked and/or serviced. A good flush, maybe a new thermostat, and ensure the fans are working for a start. A proper functioning cooling system should remain stable (3 bars) through all of the rides you describe. As a note....I have ridden mine in very similar conditions, including traffic in Palm Springs where the ambient temp was over 110 F, and the bike never went above 3 bars. Up and over many high passes in CO and the temp never budged.

 

[jfheath]

I’ve never seen the temp indicator go above 3 bars. My A6 used to get ‘tired’ in the hot summer climbs in the Pyrenees and Picos in Spain.The engine started to feel ‘tight’, which is not a diagnosis but my imagination thinking what was wrong. The pre-2008 models used to run weak, and pinking lightly was common under load and at higher altitudes. It was mentioned in the handbook manual. A brief rest to let it cool and all was well again. I found that higher octane fuel, and quality fully synthetic oil stopped it from doing it - but I’d done over 30k miles before I found that cure - so maybe it was just run in.

 

[W0QNX]

You are LOW on coolant and probably have air in the system. Take the cap off the radiator and make sure it is topped off running out full. I would even leave the rad cap off and run it with it tilted slightly with the rad cap high to purge it of air bubbles. Be sure the coolant is circulating in the rad. Close it up then make sure the overflow bottle is up to the max line. ST1300's can have small leaks on top of the engine that can be overlooked for years (without problems in my opinion) but you have to keep the overflow full.

Try filling the rad then ride again and see what happens.

Mine never went above 3 bars that I can recall.

 

[Sadlsor]

I can't say I recall ever seeing mine go above 3 bars.
2008 ST1300A.