Re: Contact breaker backplate seized and some general ignition system questions
Posted: Sun Sep 28, 2025 12:13 pm
I've used the bike over the last few weekends trying to keep it above 3000rpm on the road, and aside from a crappy idle when cold which settles down when warm, I noticed the 2700ish pinging noise seems very pronounced when cold and blipping the throttle through the revs, and it appears to be coming from the lower front cover area which suggests either:
A resonance related timing chain rattle - as mentioned above, a worn chain would tally with the maxed out retarded back plate setting. It did quieten down as the engine warmed up.
Or
The advance weights are catching on something as they move outwards, which seems unlikely as if this was the case the noise wouldn't disappear at 2800 rpm! To rule this out, once it cools down again, I could pull the front cover and see if it makes the same noise...
Or
Its pinging and just resonates at the engine case to the front..
Not managed to see the specialist chap yet due to reasons beyond my control.. hopefully get an update this week.
A resonance related timing chain rattle - as mentioned above, a worn chain would tally with the maxed out retarded back plate setting. It did quieten down as the engine warmed up.
Or
The advance weights are catching on something as they move outwards, which seems unlikely as if this was the case the noise wouldn't disappear at 2800 rpm! To rule this out, once it cools down again, I could pull the front cover and see if it makes the same noise...
Or
Its pinging and just resonates at the engine case to the front..
Not managed to see the specialist chap yet due to reasons beyond my control.. hopefully get an update this week.