Hi !
Sorry to hear about that one - I can relate to this.
Had the same prognosis you describe, limped it all they way to mates house, and then to E2R - I was lucky not to have anything pull through the motor, which I guess in your case as well, as that could have made things worse !
In my episode I was told " riding her to hard " caused the exhaust rocker arm to fail - but this seems to be rather common thing on the early 690's (Pre 2013), quick google search will reflect this.
I had 15K on the clock when this happened .. 2K after buying her

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Do you have the invoice for what they quoted you on or said what the diagnosis was in the end causing it to fail ?
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I installed a manual cam-chain tensioner and kicked my girl up a tooth in front from 15 to 16 based on recommendations if you are going to do some prolonged highway speeds (120+).
Also considering silicone hoses as this should also keep the temperature more constant - this will need to be ordered from E-bay though....