Sorry, I cannot tell you anything from the recording. I did not discover my issue until my regular service interval at 24,000 and the valve to rocker arm clearance is checked. The service identified tolerances that were out of spec and then they pulled the cam shaft. Then they noticed the excessive wear on the rocker arms. With the Technical Advisory in mind/hand they concluded that the DLC on the rocker arms was exhibiting the criteria in the Technical Advisory... and then the Warranty was invoked. To be candid, I wear ear plugs 100% of the time when I ride and I did not notice any excessive noise. I suspect more noise is possible from a malfunctioning Cam Shaft Chain Tensioner, like I also had.

I have obtained a workshop manual and found the location. Will have a look tomorrow to see if I have one.

You seem to know more than I do so I don’t want this to be argumentative. I recall the BMW mechanic saying the newer models have a different air filter assembly. To me that indicates a design flaw. I am not able to verify this however so not sure. I would also say it seems hard to determine if the seal is good when you insert the filter plastic assembly. You can see the holes connected and and a good seal on the plastic tray but knowing it seats right once that assembly slides into the bike is another thing. I guess when the top mechanic at a large BMW dealer can’t get it right then it seems like a design flaw. I really liked that bike and will miss it. I hope the pre-filters do the job. My dealer is pushing all owners to install those as a precaution.

I just sold my 2019 F 850 GS adventure. At 25,000 miles the valves were bent and I had to replace the entire head assembly because the airbox allows dirt in the motor. I did all of the scheduled maintenance at a local BMW dealer and since I was just past the warranty of three years much of the expense was out of pocket. The dealership did an amazing job going to battle for me to get BMW to pay for 2/3 of the cost. I discovered the issue when I was going through a lot of oil. I noticed it was a quart low after my last weekend riding in Moab. I went to start the bike and it wouldn't start after over a minute of cranking. I thought it might be the battery so I replaced the battery and I still had a problem starting the bike, but it eventually kicked over and sounded rough so I checked the oil and realised how low it was. after pouring a quart of oil in it was marking full on the dipstick. Realizing there could be some issues, I immediately took it in for the oil change, and the dealer told me the motor had to be replaced. It’s a real bummer also because I really like how the 850 rides off-road but I had to sell it because I didn’t want it to continue to put money into this bike. It still starts hard even after replacing the head. After a lot of research, I now realize the design flaw of the Airbox letting dirt in and the workaround now is to put a pre-filter on the intakes to reduce the chance of dirt getting in the motor. So if you have an 850 and you ride off road, be very cautious and see if you can get the upgraded airbox that they are putting in the newer bikes. Check your oil more than you think and if you are starting to burn oil, sell your bike as fast as you can. I will now use a pre-filter on my 1250 GS just to be safe but it does not have the design flaw so it is not as common of an issue.

Bars fitted. Battled a little bit with the LHS bottom mounting plate, but otherwise fairly straight forward.