Engine rattles !

[mrtee43]

Well, just come back from a 30 mile trip collecting something, and had to endure the rush hour traffic and sweltering heat and stop start progress. Bloody hell, these engines are noisy and rattly when hot.

I know it's a twin and all that but does it have to sound like the camshafts are knackered ?

Yes I do wear earplugs so it must sound a hell of a lot worse without them.

 

[brut33]

Didn't the fan kick in to cool it down...

 

[mrtee43]

Didn't the fan kick in to cool it down...

Yes all the time.

 

[seahorse]

The demo bike I rode rattled like a bag of spanners when cold

 

[roamer]

my gs has a bit of a noise,,,the twin cam and 1150 rattled a bit,
it's done just over 4 k and loosening up. I suppose it's a bmw boxer noise ,
not sure if it's the spur gears driving the cams rattling at idle
it usually gets drowned out by the induction roar,,

 

[MrMcNamara]

They do rattle more when hot & in slow traffic - mostly in light throttle at low speed. most, if not all of the rattling goes on around the clutch area (think its backlash between the clutch basket outer drive gear ring & pinion gear) Spur gears on the cams also prone to backlash (there is a factory max tolerance) My clutch / gear change also gets much more lumpy, the more I trickle through traffic / hold her on the clutch. Neither of my three previous boxers had anything other than the usual 'throttle body tick at idle at high mileage. I don't think the fairing helps the situation ref amplifying the noises? Mines got 5.5k on & brilliant once able to open her up in the hills but not brilliant around town. don't let it put you off an overall brilliant bike!

 

[adventuredon]

so creating a water cooled engine has actually created a noisy beast at slower speeds in traffic? Surely that would have helped keep everything cooler or was that not the point? Or am I missing something?

 

[MrMcNamara]

The water cooling is quite specific - its only around the cylinder / head area, there is no separate oil cooling. There are lots of additional gears, not previously within the boxer design, in particular spur gears in the cylinder heads & on the new 'wet clutch' set up. None of these are fitted with anti backlash mechanisms & will therefore rattle when not under load (spur gears -increasing revs /clutch - transmission loading) The engine has become a bit of a mismatch of old Boxer layout & new bike technology. This does not stop it being a brilliant engine when pushed, with plenty of old school grunt when required, just a shame the gearbox / clutch / noise issues lurk in the background.

 

[Prawnini]

Don't worry, ya won't hear it on the move with those damned Annakees............

 

[Toothless]

I've heard this rattling noise too...when driving with engine revs around 5000rpm...(6th gear on the highway)...
You don't hear it when you move your head more sideways or more to the front or back.
I presume it's a kind of mechanical noise emitted from the airbox, or maybe the injectors...
The sound resembles an engine with a big end or crankshaft bearing failure...
It goes away just as you load the engine a bit more (throttling up)...but is back as soon as you maintain a certain rpm after accelerating.
I put my windscreen in the lowest position so I can't hear it through the turbulence rumble