Rod knock?

[oddnumber]

Can anyone describe what a rod knock sounds like? I'm getting a tapping sound when the engine is hot on my Dragstar - I'm hoping its just noisy valves. Might seem a daft question, but does a rod knock sound like a 'knock' or a 'tap'? :o

Ta for any info :)

[lowrider]

Old trick,get a screw driver and stick the blade on the bits of the engine you want to listen to and your ear on the handle end.
Longer the driver the easier it is. ;)
You will soon be able to find out where the noise is coming from.
Plus it is fun the first time you do it,listen to stuff whirring away :D
But what is "rod knock"?
You mean small end knock?

[Dougie]

Don't know if Dragstars are prone to it,but it could be cam end float.GS Suzukis (all sizes) are notorious for it and if it is it isn't really owt to worry about.However to put yer mind at rest I'd advise trying to find a Dragstar site and ask there.

[lowrider]

However to put yer mind at rest I'd advise trying to find a Dragstar site and ask there.
Good idea,they would know you would think

[trikerdrew]

horrid aint it that weird noise.

From my mechanical mayhem I can profer the following.

top end is generally a tick/rattle type of noise.

Bottem end shells(where con rod connects) make a noise that makes grown men cry.It is a bass level tick that gets progressively louder the worse it gets.Hence people say big ends are knocking-cuz it sounds like they are trying to get out just before lump seizes.

Does noise remain constant?

I'd look at top end if it happens when it gets warm.Valve clearances would be first on my list.Easy job for piece of mind.Then cam chain tensioner-make sure it works.

All the best

Drew

ps where you at?

[gothtec]

Constant Knock. knock. knock...?

On the left side?

When the engines hot?

Only hear it when stopped at lights?

If so, mines doing that too :confused:

[oddnumber]

I couldn't work it out - the noise was only there after the bike had warmed up, not when cold. That made me think it wasn't the valves, because surely when hot the tolerance gets less?

Anyway, I nipped it to the local workshop and they had a listen. They said the noise sounded like a loose valve after all. Its still under a bit of warranty so I've got to take it back in to where I bought it from to be sorted out.

Gothtec - this wasn't really constant, it varied with the revs. Is yours doing it when hot?

[gothtec]

Mine disappears under revs (or is hidden by)...

Its regular when idling...

I'll take it to the shop ( just out of warrenty) and let them listern (again). I might be catching a problem before it gets bad.