If you would have had problems, you'd know it by now. It's not an issue that pops up later, it shows itself right away...continuous high rpm >3500k will manifest it. You either have it or you don't.

Not every M8 experienced sumping.

My 2019 114 is an original oil pump design and no sumping in over 40k miles.

So, if it is something you worry about top the point of not enjoying your bike, then just have the oil pump replaced now, less cost that ESP. And I'm not sure the ESP will cover sumping as it is very difficult to diagnose and repeat (unless your engine grenades).

My 2019 Limited 114 and my 2022 Softail Heritage 114 are both flawless in that I have no sumping, no oil in air cleaner, and once the kit was installed on the 2019, no trans fluid migration to primary.

 

If you really want a ESP get one that is aftermarket like from Jim Palmer

 

You can visually check if you have the latest oil pump by removing the cam cover and looking for the tab on the oil pump.


Also here is an image of what to look for. You just need to remove the cam cover (probably and the exhaust) to get a look at the oil pump.

https://static.nhtsa.gov/odi/tsbs/20...64800-9999.pdf

 

What was the cause of the head gasket failure?

 

Your guess is as good as mine. They seem to fail on the exhaust side.

This is not my picture (credit: Havinabubble), but both mine looked the same - as did several others on this forum (LINK).



Or here:

 

Hopefully the newer high-compression 121s will not have head gasket issues...

 

I think it was mostly the early M8 engines, prior to 2019-ish. I don't think there were any changes in the part number for the gasket, but I don't see anyone complaining anymore.

 

My 2019 trike (build date 11/18) did that, at about 5200 miles. Switched to Cometic gaskets, I believe it's cured.