Chain advice

[darrsi]

I'm not quite sure what your picture is showing us, if it's to show there's two separate joining links, I can't really see them not even one if I'm honest.

Endless chains such as what Yamaha supply or fitted as standard have a pended end rivet, the shape of which are a square with 4 bevelled edges, the pictures shows only this type of links.  The joining links supplied with non endless chains, which make up the vast majority of replacement chains are expanding pin type, this type is seen in your picture of the sprocket and is located at 3 O'clock position.  Yes you can get factory type rivet joining links, in the replacement non endless chain kits, but these require a special anvil tool which is very, very expensive, time consuming and very tricky to use in the vertical position while the chain is on the bike.  These are used in my experience, when making up endless chains before there are fitted, to custom or drag/race machines with non standard swingarm lengths, not when doing routine servicing for road bikes, in which case the expanding pin type link is used. 

I've fitted many chains both endless and the more common non-endless chains over the years.  I've never fitted a pended factory link to non-endless chain while the chain is on the bike and I don't know of a stealer doing it either, it just too difficult, too expensive and time consuming 99.9% will be expanding pin links which are perfectly acceptable. 

Using your pictures as a ref, the chain is out of spec and needs to be replaced as it's over the 150mm length over 11 pins.  Another fairly reliable method and is alluded to in another post, is pulling the chain off the rear sprocket and being able to slide a pencil in the gap.  Another way is trying to push a link together if you can feel movement (slight knocking) the chain is buggered.

The chain fitted to this bike isn't OE it's a non endless expanding pin link replacement.  Like many it's service life is short buggered the bike only having covered 24k.  That's a minimum of two chains in less than the expected life of one chain, why?  Lack off proper maintenance, use of spray on lubs and/or bad fitting of the new chain, not changing both sprockets and more of the above.

Mate you need a new chain and sprockets change them both at the same time.     

 

There's a link next to the bolt on the right of the swingarm in the picture. The other one is out of shot. Doesn't look like it's been splayed enough to me, but i agree everything is pointing to changing sprockets and chain, for peace of mind if anything.