Jump to content

'Tappetty' old engine


Recommended Posts

My GN125 is from 2006, 30,000 miles on the clock. A couple of years ago the engine developed a nasty top end noise when I was on a motorway. Not feeling too confident working on bikes myself at the time, I took it to a bike shop. The problem was a worn rocker arm, which they replaced. Ever since then there's been a slight top end rattle, best described as tappet noise. The bike shop assured me the valve clearances were checked and this noise is normal with small engines, when they've done a bit of work.

The bike has been reliable since, despite the noise. I'd quite like to get rid of it though. The noise that is. A couple of questions:

Is it normal for an older engine to become more noisy?

The valve clearance range on this bike is quite wide. Generally speaking, would a bigger or a smaller gap tend to cause more tappet noise? I guess I'm thinking along the lines of adjusting the clearance to close to the specified limit, bigger gap or smaller gap, whichever one makes the engine quieter.

Cheers for any replies.

Link to comment
Share on other sites

When they repalced the worn rocker arm there was probably other parts that were slightly owrn but not too bad.

The rocker arm is mounted on a shaft, this could be worn.

The range of valve clearance gaps genrrally allows for the difficulty of settign them precisiely.

I always make sure the minimum size feeler is loose and the maximum won't go in.

Link to comment
Share on other sites

An engine would be quieter if the gap was smaller

But running a smaller gap you run the risk of needing adjustment sooner rather than later

you also run the risk of the valve been slightly open if the gap gets tighter which could cause poor running and burn your valve seats out

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Sign up now

    Registration is quick and easy 

  • Create New...

Important Information

Terms of Use Privacy Policy Guidelines We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Please Sign In or Sign Up