Reply To: Valve clearance, camshaft, camshaft tensioner – a problem or a serious fault?
Late yesterday evening, or rather at night, I started my motorcycle.
The noise is still audible. Following your recommendations, I would replace the timing chain tensioner, but with the engine running, I gently pulled back the tensioner and had to pull it back quite a bit to hear the chain noise, so I’m guessing that’s not it…
But I tried to locate the noise more precisely and it seems to be coming from the exhaust pipe of the rear cylinder, at least that’s what I hear.
This raises the question, could it be something to do with the piston? Could it be something to do with the valve springs?
The noise is cyclical, I have the impression that the valve spring is broken or worn out and does not retract the valve and hits the cylinder. I don’t know, maybe I’m fooling myself with the easiest version of this problem, but I prefer to eliminate all unwanted faults rather than remove the entire cylinders and replace the pistons with rings…
The bearings and their mountings were fine, I didn’t hear any noise from the bearings when I had the camshafts removed.
During disassembly, I did not remove the crankshaft bearings, so I have no idea what condition they are in.
Overall, the motorcycle was difficult to start without choking.
After starting it and letting it idle for a while so as not to seize anything and to allow the oil to spread everywhere, I tried to gently accelerate, but it did not respond and even stalled.
After running for a while, gently operating the throttle, it couldn’t rev up, as if it were sluggish when opening the throttle (despite smooth movements, no jerking of the throttle).
Overall, it was smoking heavily, and it was hard for me to tell if it was because it had been standing for so long, because the engine was cold, or because I had poured oil on the pistons for the compression tests. The exhaust fumes did not smell strictly of burnt oil, it was a bit like burning a 2-stroke mixture, I don’t know how to describe it.
In the evening it was cooler, but not enough for the steam from the engine to be visible.