Possible Engine Sound

[Yamazer-92]

Went for a great ride today, however have been noticing another engine sound recently. Bike has slight cam chain ticking noise for first few minutes until warm, bit annoying but not too worried been told it's normal. I am now noticing however that in 1st and 2nd gear especially, when accelerating hard and putting the bike under load there is a knocking sound from the engine that always occurs at approximately 3500rpm. This is worrying me a bit, the performance is fine however and it never does it on deceleration only under load. It also doesn't do it in neutral when revving I don't think although I will try that again tomorrow holding it at 3.5k as I don't think I tested that properly. I don't think the noise occurs in 4th and above strangely at those revs and the bike pulls cleanly all the way through the revs. Might take it to a garage to have a look at, if it's something bad I might just rip the bike apart and sell it for parts because it seems every time I fix something it works great for about 2 months and then something else decides to break...

[Paulfzs]

sounds the same as mine, mine was about 3-5k then pretty much gone at 5k, if you give it a handful of beans up to about 90 does it feel like the engine is a bit tight so to speak?


does it only start when hot?


mine was only when hot about 4-5 miles gentle riding and would only happen about 3.5k but dissapear if i get to about 50mph 6th gear revs whatever that was and would only return if i open throttle a bit quick.


eventually sounding like this

[Yamazer-92]

That sounds a lot more severe than mine, it's hard to describe the sound really as it's over very fast. I can only really say it sounds like a normal 4 cylinder accelerating from tickover to 3.5k, then has a weird sort of parallel twin sound for a split second but it's definitely still running on all 4 cylinders, then normal 4 cylinder sound again all the way up the revs. Engine doesn't feel tight or anything although not sure how a tight engine would feel, it feels like it has always felt just I've recently picked up on this sound.

[Paulfzs]

Not sure how to describe the tight feeling but clearly your issue isnt the same as mine just the same thing cause it, get a video up

[Yamazer-92]

Took the bike to work today and was listening out very carefully on the way home, visor open leaning in close to the engine. So carefully that I almost drove into the kerb at one point! Anyway the sound is actually from the exhaust can I've now realised, fairly certain anyway, it must be some weird harmonic thing or a vibration but definitely not engine related so I am relieved about that. My Mivv exhaust has been on for a couple of thousand miles now so maybe some of the packing is wearing in a bit, it's pretty bassy though even with the baffle in.


The bike almost at 29k now and I think I'll get the valve clearances checked at 30k just to be safe. Does anyone know how much that costs roughly? I know how to do it, but I don't have a nice clean and covered from the elements area to work in and have never attempted it before so wouldn't want to mess anything up. I also don't have feeler gauges so think its worth leaving to a professional.

[Paulfzs]

on a fazer labour will probably add up a lot theyre a pain to work on.


have you checked the header bolts are all on tight?

[His Dudeness]

You could check the clearances yourself. It's a bit fiddley but not that hard. The clearances on a fazer are more likely to tighten as the valve wears into the head so they get quieter which is worse because the smaller clearance means the valves are held open longer so they have less time to cool against the head which is why they burn out if you leave it too long between adjusting them. Not saying that's likely on your bike it's just what happens eventually. The older style tappets tend to loosen so they get louder and you hear the distinctive tappet sound.

[Yamazer-92]

Thanks His Dudeness for the info, like I say I have the theoretical knowledge of what the procedure is but it only takes one cock up or one seized bolt to make it into a really bad day. Then again, I do like a challenge but if I do decide to go for it I will need to find a nice flat clear area as all I have is a slightly slanted bit of concrete outside that even when swept has little stones, grit an watnot blowing over the place. Some of that in the engine could be a nightmare... I think when the 30k mark comes I'll go to a couple of garages and get some quotes and if they aren't too outrageous I'll leave it to them.

[unfazed]

Take it into the Kitchen