Engine rattle!

[guest1540]

Hi all,
I'm really enjoying my XBR cafe racer and I've clocked up just over 2k this summer. During an 800 hundred mile run to the South of Ireland last weekend the bike ran sweet but on the way home she developed a worrying metallic rattle on the over run.This noise is not present at start up and only becomes evident after a quarter mile or so. When you stop, the noise begins to reduce on tick over and disappears after a minute or so.   I have checked the valve train and tappets. I then checked the clutch etc and then the rotter side - I couldn't find any obvious cause of this metallic noise. Has anyone experienced this problem? Any suggestions about a possible cause?
Any help/advice greatly appreciated, Sean.

[chris22]

I have just joined this website have newly acquired an XBR 500 to rebuild. I had previously owned a Suzuki Savage single which developed a rattle similar to yours and turned out to be a loose baffle in the silencer.
If not that, you could use a long screwdriver to place on the area where you think the noise is coming from as a vibration stethoscope.
Good luck.

[Propellor]

Hi all,
I'm really enjoying my XBR cafe racer and I've clocked up just over 2k this summer. During an 800 hundred mile run to the South of Ireland last weekend the bike ran sweet but on the way home she developed a worrying metallic rattle on the over run.This noise is not present at start up and only becomes evident after a quarter mile or so. When you stop, the noise begins to reduce on tick over and disappears after a minute or so.   I have checked the valve train and tappets. I then checked the clutch etc and then the rotter side - I couldn't find any obvious cause of this metallic noise. Has anyone experienced this problem? Any suggestions about a possible cause?
Any help/advice greatly appreciated, Sean.

If it is an internal noise, engine related, in the old days a knock or rattle on the overrun was usually suspected to be something load related. Namely one of the ends (big or little!) or the piston. Valve gear is not really load related, but it may be that the noise is masked by other noises and you actually only hear it on the overrun?

As the other post suggests, check the simpler stuff like loose exhaust, final drive chain etc. We assume everything engine oil related is in order?

[guest1540]

Sorted!!!! You were both right - I gona put a big sign on my garage wall "CHECK THE SIMPLE STUFF FIRST".
I fitted a one off exhaust system when I built this bike and I brazed the original collars onto the new headers. The left hand collar had cracked but was still held in place by the other pipe. I would never have found the cause of this "rattle" had I not striped the exhaust system. So thanks guys and thanks to the Thumper Club family in general for maintaining this great site.