Rattle in the silencer
 

Hi!

I have recently returned to my bike that I crashed in May this year. It's a BMW F650ST (1997). The bike is running well, but at revs of over 3000, there is a rattle that appears to be coming from inside the silencer. It fell quite hard on that side, so I fear something has come loose inside. Short of replacing the whole thing, is there something I can do to fix it? Or is it possible it is something else entirely? It seems to be vibration related rather than directly Revs related... Any help would be great. Parts are not easy to get here. Stuck in Sarajevo, Bosnia.

Thanks!?c?

If that muffler/silencer is constructed as all other that I have used and opened - do not worry. Just keep on riding.

Should the rattling sound be nagging you, not the bike, you will most likely need to install another "sound-diminisher"... which frankly is more of a waste of money and time.

What usually happens is that the back-pressure (volumetric degree of filling of the combustion chamber) will be negatively affected = loose power and torque. It is a middle "wall" that has become loose. To fix such a "damage" you will need to cut open the "can", and re-weld it from the inside... - way too much work, and costs both of money and time. If you can live with that - just keep on riding.

:scooter:

Thank you so much! There is no way to get into it other than cutting and welding, but that does sound like too much effort... I am so happy that you say that! Cause keep on riding is what I want to do. So badly.
As for the noise, Loud pipes save lives right? Maybe that will stop me from being hit be a car again...:scooter:

Time for a beerbier

...rattle-snake ;)

How is the front-wheel doing?

...totally missed that knee-thing. Hope you'll get fully recovered. Do not understand the diagnosis they gave you... a pulled patellar tendon means a draw-box(?) (lig. cruciforme(?)) injury with residing knee-instability. It almost always is associated with an initial swelling of the bursae... Or did you only get hit hard on the tendon just below (distal of) the patella? Damages to the cartilage of the joint? Hip? Pelvic/lumbar area? If knee is knocked backwards that hard, it will affect the hip-joint, pevic and lubar areas as well... fibula?
Avoid getting hit by objects, especilly large once like cars! It can get so darn unconfortable with way too much nociceptic activity ;)


Large pannierns, and a sizeable fairing, are helpfull extras! Saved my left leg back in 1989 :)
Making the bike apear larger helps getting car-drivers attension ;)

I've had this problem twice; annoying rattle / tinkle, just at the speed you want to cruise at.

One turned out to be a piece of road (small pebble) that had got into the silencer after a small off. Have you had the can off and given it a good rattle ?

The other time (different bike) I thought it was the same issue but some of the internals had come loose. Rather than cut the can apart, I used a 40mm hole saw to gain access in a couple of places and welded a few braces between the internal baffle tube and the wall of the can. I then welded the "holes" back in place.