[nuttyrailwayman]

Hi, when my engine cold, it knocks. Not a rattle, but a metalic knock. As soon as engine warm, ie temp gauge moves slightly it goes. Was hoping new oil would quieten it but no, it hasnt. Im dreading the thought of a big-end bearing going. Could just be piston-slap tho. Any comments or suggestions would be helpful. Its quite urgent, i have a 270mile commute every week. Last thing i need is for the engine to go bang, I love my TA!!

 

[russh]

Hi,

It's obviously quite difficult to asses an engine noise over a forum however I find my engine a bit knocky, I presume it's just the characteristic of it. It's sounded like that since new, and is now at 10k miles (2 years old), it could be down to the uneven firing order of the V-twin?? not sure.

Ear plugs seem to fix it

 

[Raven]

Mine has done that since new, so (hopefully) it is absolutly nothing to worry about .

 

[Steve C]

Hi, when my engine cold, it knocks. Not a rattle, but a metalic knock. As soon as engine warm, ie temp gauge moves slightly it goes. Was hoping new oil would quieten it but no, it hasnt. Im dreading the thought of a big-end bearing going. Could just be piston-slap tho. Any comments or suggestions would be helpful. Its quite urgent, i have a 270mile commute every week. Last thing i need is for the engine to go bang, I love my TA!!

Now I'm no spanner god, unlike many on here... but... Worth checking your chain tension railwayman. Even just a snitch too tight gives a knocking sound at tickover on my AT.
If not that, and just to settle your fears, a screwdriver used like a stethoscope is great for identifying where in the engine the noise is coming from.

 

[Kakugo]

Agrre with the camchains, but do not rule oit the oil pump chain. Mine has become quite rattly at cold but, since you need to take off the clutch to put it right, it's staying right there until I'll refresh the clutch plates and spring.

 

[The Pheasant]

Agree with various possibilities mentioned but IMO unless the motor is high mileage (60,000+) or has been neglected the noise is most likely slack cold clearances that close up as the oil and engine warm. My 650 Alp sounds rough around the rear cylinder when cold but is smooth as once warm.