Bantam D1 Engine Noise

[maddogb31]

Went out for a little run today and had the GoPro on, noticed the engine was a bit noisy, I have electronic ignition which has been set up as instructions, standard carb fitted with standard jet/needle position, plug is a nice tan colour and I have good compression.
If you have a look at the video the noise comes and goes depending on revs.
I have posted the video on my YouTube channel... Any comments/ideas welcome.
Thanks Ian

Video link:
https://youtu.be/NgjTnhe9lBo

[Spaceman]

I've listened to the video a couple of times and convinced myself that I can hear a background whining sound at times but it is difficult to be sure from all the other noises whether this is an issue or not. What would really help is if you could pick out a couple of time code periods from the video where you think the noise is most prominent?

[maddogb31]

There are a few but the most noticeable are 5:42 to 6:10 and 7:31 to 9:50, more of a rattle than a whine.

[Spaceman]

With the bike moving along at 30 mph, it is difficult to tell what's engine noise and what might be wind induced noise. In the second time slot, I can sort of convince myself that I can hear a high pitched rattle but, I know from experience, trying to isolate this this somewhere on the engine or in the transmission can be very hard.

If it was me, I would start by assuming it's external to the engine and check the possible sources for a rattle, especially the rear chain and sprockets and all the bodywork. Depending on the type of silencer fitted, it might be worth checking to make sure the baffles aren't rattling if that is possible.

[maddogb31]

Thanks for the reply, got a few things to go on there.