I've got two hours spare this afternoon.....

Originally Posted by Scoobs

Pinking is pre ignition. When the fuel combusts before the piston reaches top dead centre of it's travel. It is caused by bad timing, poor quality fuel amounst other things. I think knocking is the same.

Almost.

Ignition is generaly timed to occur before Top Dead Centre anyway (because the crank/piston is still moving when the spark occurs, the piston/crank has gone past TDC when peak pressure occurs). Pre ignition is just when the charge ignites before the spark fires.

Knock is slightly different. The fuel is ignited by the spark as usual, but before the flame manages to burn all the fuel, the increase in pressure/temp causes the remaining unburnt fuel to spontaniously combust.

[21QUEST]

Originally Posted by rictus01

it acts between the brake pad backing and the caliper pistons (metal on metal) their is a small amount of movement between the two surfaces which causes the noise without any lubrication.

Cooper grease has a high failure temprature than normal grease.

Cheers Mark.

That is quite right but that is not always the cause of it. Contaminated pads/discs can also cause the it.

Cheers
Ben

[northwind]

Originally Posted by rictus01

Question:- do you smoke

Not while I'm fitting a dynojet kit, no

Eh, Rictus, that reminds me, are you not diabetic? Or am I making that up?

Originally Posted by Flamin_Squirrel

Almost.

Ignition is generaly timed to occur before Top Dead Centre anyway (because the crank/piston is still moving when the spark occurs, the piston/crank has gone past TDC when peak pressure occurs). Pre ignition is just when the charge ignites before the spark fires.

Knock is slightly different. The fuel is ignited by the spark as usual, but before the flame manages to burn all the fuel, the increase in pressure/temp causes the remaining unburnt fuel to spontaniously combust.

FS! I stand corrected!