Originally Posted by Dude
Just bought an 06 R1200RT and I'm noticing a slight tap or knock from the engine at low rpm when starting out in 1st gear. Sounds a little like wrist pin knock, piston slap, or spark knock, but only does it when blipping the throttle from idle and when taking off from a standstill and immediately goes away as rpms increase. Does not make any noise under hard acceleration once moving which is a little confusing.
Anyone have any ideas? Anyone else hear this on theirs?
Unless I'm mistaken, Ben in post #2 is being sarcastic. "They all do that".
If I'm wrong, I'm sure he'll let me know.
Sometimes, when taking off in first gear my current RT knocks so loud that I think it's gonna grenade.
I've owned 4 R1200. An '05GS, '08GS, '07RT and my current '05RT
As I recall, to some degree, they all made the noise that you're referring to .
Definitely my 2 RTs. Maybe the bodywork funnels the sound somehow.
Not one of my favorite chacteristics of the machine. I'm just rid'n mine and try'n not to obsess about it.
You can read plenty about final drive issues, and there was the key ring antenna (EWS) failures, front rotor/wheel judder under braking, clunky shifting trans.... etc
But, even with all the boxers out there, I don't recall seeing much regarding catastrophic internal engine failure.
Just read recently on one of these BMW sites of a guy with a similar concern on his RT. Said he rode a demo at the BMWMOA International Rally in TN. That one didn't have the knock. He was perplexed. Wrote that he rides 2-up with his wife. Come to think of it, both of my RTs were purchased used and both had been ridden 2-up. One of them exclusively 2-up for a road trip of 8,000 miles the other owner said "some". Didn't like him. Don't know what that means - some. That's 3 RTs in my small world which all had/have the knock. All ridden 2 -up.... HERE I GO, OBSESSING AGAIN. lol
I don't have the answer. Someone here in this thread mentioned loose tolerances of air/oil cooled design.
Post-up if you learn something about it.