[TurboLag200]

Hello All! I own a 2021 Honda Highness CB350 run about 5300km. It has completed 3 services and the oil has been changed 2 times, Once after the break in period so after one month, The second one was after 6 months during the 2nd service, Then 3rd service was well general service except the oil change. Now for the past few months i have been noticing odd sort of knocking or clunking noises coming from the engine. Both times when its cold and when its fully warm. It sounds very odd and is quite loud too, I always notice it when im idling at a red light and as im revving it. I am not entirely too sure what can be causing this sound or its normal. I would like to request fellow members and CB350 owners to confirm whether this sound is too noticeable on your CB350. I will include a sound clip of it for better context. It's not very noticeable so you will have to listen very closely. Cheers.

https://www.youtube.com/watch?v=ja6HNJTXbo0

[Mustang_Boss]

It sounded like Tappet noise. Something is wrong in the head, which is causing that rumbling noise. Valve clearence issue or Tappets issue. This is the reason why you didn't get a clean start. Timing chain also does cause some of these issues. (MisFiring)

My laptop is not a macbook and its audio is just ok. So, this is what i could understand.

[aargee]

Originally Posted by TurboLag200

Now for the past few months i have been noticing odd sort of knocking or clunking noises coming from the engine. Both times when its cold and when its fully warm. It sounds very odd and is quite loud too, I always notice it when im idling at a red light and as im revving it

Hello Sir, this is indeed the tappet noise as Mustang_Boss has pointed out.

Kindly do one more test if possible please - Observe this clunky (chik-chik) noise when you're ready to ride (after the auto choke has stopped & the engine idling has fallen to optimal) as well as after a good ride (operational temperature), say when you've ridden for half hour. Record the noises if possible as sometimes human mind can be deceiving. The additional noise at cold temperature should be more than the noise that comes after the ride. If so, you can be 100% assured this is tappet noise that can be easily fixed at ASC.

But from the video I deduce that the noise is not that bad & can withstand for few more 1000 Kms

[CLASSICREBORN]

This is definitely tappet noise. The noise that has been literally a nightmare for quite a few Royal Enfield users. This is the first time I am seeing this on CB350 though. This is a normal thing. The sound is not that bad. I feel it is slightly out of adjustment. A quick visit to the service centre should get it sorted and also check the timing chain. I have a Reborn and no matter how many times the service centre adjusts it , after sometime it again goes back to almost the same state. I stay at Siliguri,West Bengal. There are 3 service centres of RE here and have visited them all and every time I have come back with the same result.I have ridden my bike for 15000+ km and touch wood nothing has gone wrong. It is just that the sound is irritating.
So final point is get it adjusted at a Bigwing Service Centre and enjoy your ride. CB350 is a really good bike as far as I know. Cheers.

[Fastdriver]

I think it may not be the typical tappet noise as it sounds something different to me than tappet noise. Maybe I am wrong. Please consult with a good technician at Honda BigWing service as soon as possible to avoid further possible damage.