JamieDemos wrote:Hi all, I've noticed a tapping noise coming from the top end of my engine for the last few months, on my nc30. The engine has 40000km on it.
Sounds like a metal tapping/clicking noise, definitely from the top. Im not sure if these engines sound like this or if I need to worry. Its most audible at lower rpm once the engine has warmed up.
I checked the valve clearances a year ago but only on the back cylinders and all was fine. Could this noise be caused by bad valve clearances?
Thanks for any input.
Perhaps this will sound harsh but there are t literally dozens of posts from people in South Africa who all say this kind of thing. "My engine started making a funny noise, so i drove it a couple of more months and now it is dead completely"
What is with all the mechanical unsympathy. Why would you continiue to ride something that sudeenly starts making a strange noise without investigating the problem first.
If you had a baby that started to make funny noises you wouldn't just ignore it right.
Why would you only check the rear cylinders? It's like a doctor attempting to do a quadruple heart bypass and only bypassing the first 2 blockages.
Not doing yourself of the engine any favours. Allow a little more time to complete a job and read up on it before you start and you'll have a much better bike.
Onto the issue at hand.
"Engine tapping noise"
Is it there from starting up the engine? Does it get worse when the engine is warmed up or does it go away or stay the same?
Does the noise speed up / slow down with the revs?
1. Exhaust headers can be loose, these cause a rattling sound as if from the engine and are easy to check they are tight.
2. Valve clearnces could be out.. worse thing is not to get these set, if they are too far out you can easily blow up the engine
3. there could be oiling problems wiht the top end, causing metal to metal contact / wearing out the camshaft / rocker as mentioned above, this is also very bad and parts will need to be replaced.
4. Could be some other bearings failed or something loose vibrating about.
First port of call would be to get the front clearances checked, its a pain in the arse job but so long as you dont rush isnt the end fo the world, service book is in the downoads section if you dont have it, uner general maintainnce chapter 3 i believe you will find how to do clearances. there are also guides on here. inthe workshop section so you can get a good idea of how to do it correctly and what you need before starting up. id allow at least half a day to do the clearnaces withotu rushing. Check everything twice. If your doing the front you may as well check the rear head too agian, write everything down on some paper so you have a reference chart, put the distance bike has covered as well as date checked on it too
While you are doing that you can check your exhaust pipes are not loose (check front and rear) there are clamps on a stock system too that can rattle and sound higher up than they are.
Once you have