Out today on my 2013 Evo 4T and noticed a strange noise.

Sounded like a chain slapping on metal.  Only occurred in the higher gears, 1st, 2nd, and 3rd all normal.

Regular "clack clack clack" about twice a second.  Seemed to get a litter quicker with speed and stopped with the clutch engaged.  Anyone got any ideas?

 

Need clarification when you say clutch engaged do you mean lever pulled in?

In higher gears you’re going faster which causes your chain to bounce around a lot more. The torque from the engine and loading from the back wheel and deflection of the swing arm make the whole thing a very dynamic system so a little too much chain slack can lead to large swings of the chain both above and below the swing arm.

Is your chain tensioner functioning properly? Have you adjusted your chain slack? Is your chain worn? Do you lube your chain? All things to check first.

With clutch lever pulled in noise seemed to disappear.

I do regularly clean and lube the chain but it is quite slack, although the adjuster does take up all the free play.

Did consider the chain and wheels as the frequency of the noise seemed more in tune with wheel rotation rather that the engine. Will tighten the chain a notch or two and see if this makes any difference.

 

Mine clack clacked the other week because the chains connecting link spring clip and outer link plate had vanished,  allowing the link plate with the pins fitted to back out and clack its way against the chain tensioner, luckily no damage. 

Could also check the chain tensioner is in line with the chain and not twisted, bent inwards or outwards from the normal chain line or excessively loose on its mounting spigot/ bolt..

front sprocket needs replacing?

On the two strokes It's usually the spring link hitting the head of the bolt securing the chain tensioner, it only has to slacken a fraction for contact to occur.  It may be similar on the fourstroke.  Check the bolt.  Fitting the connecting link with the horseshoe inboard gives a bit more clearance.

Edited November 20, 20178 yr by 2stroke4stroke

Thanks for all your replies.

Have had a good look at it and conclude:

Chain a little bit loose - have adjusted in line with manual.

Front sprocket OK.

Some wear from rubbing on the split link so have turned it around so clip is on the inside.

Could replicate the noise by depressing the tensioner so the chain went a little slack.  This caused the underside of the chain to "clack" on the frame.  There is only just enough room for the chain to pass between the frame and the underside of the swinging arm.  There was evidence of rubbing in this area.  May look to put some plastic protection on the frame here.

Will take it for a test ride and see if the problem is solved.

Happy to report everything now OK.