Pretty sure it's a LH thread but you still need to gain access to the actual spindle to hold with pin-nose pliers.
Look for a hole in the base of the blue housing, if it's like others I've done the access hole allows you to lock the spindle with a small screwdriver so you can then undo the trip knob.

Superb Clymer service manual for all the 1981 - 1985 models. (see pics below for model applicability)
Very little use and very clean. Includes everything you'll need to keep your steed on the road!
£27 posted in the UK. Location Whitchurch, Shropshire.

Yes, please PM me with your full address details.
Regards Will.

Just had another small amount of these sets made up after Paul Doran wanted a set. Manufactured at my friends place from Hexis outdoor brushed aluminium high adhesive backed foil with outdoor digital print and clear coat over the top. Beautiful quality. Measurements are 101mm and 87mm as per origina...

I take it this is for the 400J, 500/550 models.

I've stuck it on eBay now.
Any interested parties can read the full spec there.
Thanks.
https://www.ebay.co.uk/itm/396878625558

Would love another Z500 (I bought one brand new from Steve Hartley in Warrington in 1979).
Or even better a GPz550D1, now they are nice

Good luck with the sale, I need to sell a few before I buy any more though.

Thanks for the reccomendation Chris
I think these are what you are after?

US spec KZ650B3, 12k miles, super quiet motor, runs perfectly. Kerker pipe, original toolkit and owners handbook. Lots of history.
Very nice original condition, a few blemishes on tank and a small ding but that's about it.
Needs nothing, located north Shropshire.
£4250 ono. Tel 07955 302181

Too many bikes is a nice problem, but still a problem so I'm willing to let someone else enjoy this flawless and upgraded example. Fully built and retored by me, unlike the "standard" model this won't give you any problems. Absolutely stunning condition throughout, 650 miles since build, p...

Brilliant fix and definitely worth doing Keith. :D I had this problem on my Moto Martin Z1 in the early 90's..... and with the small amount of oscillating play, the rotor friction welded itself to the alternator windings whilst sitting at around 7k RPM on the M6. The result was that the entire alter...

Okay so this is still available.
If anyone else wants it please let me know.
Thanks.

Beautifully made polished all stainless steel chain guard for all the Z650 models.
Posted out bubblewrapped in hard packaging.

£55 inc. postage (UK).

NOW SOLD

Simon, put what you are after in the actual title... more people might then realise you only want the swing arm!

Just bought one of the LMP chain guards myself for my newly acquired KZ650. https://www.ebay.co.uk/itm/388476449335?_skw=z650+chain+guard&itmmeta=01JX2DMAZB69DQ18P9XEZBYKDJ&hash=item5a73003237:g:wPMAAOSw8rhkI0BU&itmprp=enc%3AAQAKAAAA0FkggFvd1GGDu0w3yXCmi1ftUufL72FRuCk4WVaXKDVloAM87eLN6hR...