Possible Alternator Belt Problem?

[tommygun]

Hi Chaps,

Steptoe did a fantastic job for my 12k service on the GSA yesterday but there is one thing we were stumped with. Even before the service I have a sort of 'clack, clack, clack' sound eminating from the front when pulling off or in 1st/2nd gear at just over 1200rpm. Very similar sound to the old diesel car engines.
The bike runs great and I think the noise degrades after a dash on the freeway but I was just wondering if anyone out there may have had a similar issue or is it another case of 'they all do that'?

Steptoe thinks it could be the alternator belt but there is no way of telling unless you replace the belt?

Any thoughts welcome.

 

[RickG]

is it engine speed related or bike speed related?

can you hear it when the bike is stopped and you rev the engine?

The front cover comes off esily enough, if you want to take a look. If it is the belt it's an odd noise unless it's failing and theres'a strip of belt flapping around

 

[tommygun]

Its bike speed. Sounds fine when revving in neutral. Will take the cover off this weekend and take a look.

 

[RickG]

So if it's bike speed related, and you can't hear it when you rev in neutral it's not so likely to be something that goes around the same speed as the engine like the alternator. Instead it's something that happens when you move - wheels, transmission etc.

 

[tommygun]

Yeah I guess that makes sense. It's coming from the engine for sure if I pull the clutch in and freewheel - no noise.

Maybe eventually it'll go away

 

[Steptoe]

So if it's bike speed related, and you can't hear it when you rev in neutral it's not so likely to be something that goes around the same speed as the engine like the alternator. Instead it's something that happens when you move - wheels, transmission etc.

It's almost certainly not bike speed wheel/transmission related - it sounds like a loose alternator belt flapping only as you pull away with the engine under load, just revving with no load isn't the same.

 

[RickG]

piston slap, little end?

 

[Deleted account 210609001]

Looking at the belt takes two minutes - four torx bolts and the cover comes off.

 

[tommygun]

Presumably I'll have to just get someone to turn the rear wheel while I look for any abnormalities on the belt or do I just fire the bike up on the centre stand?
This could be tricky...