Hello Stccmc,
nice to see you here, welcome
If itâs correct that youâre from Hong Kong (?) then you should be able to find a suitable tool locally, I meanâŚ
Did you try your local web search with the (translated) words âhook spanner 60 mmâ, âhook wrench 60 mmâ, âhook key 60 mmâ,
maybe âadjustable spanner wrenchâ, âadjustable âCâ hook spannerâ?
You might of course also use an adjustable hook wrench of matching size (range), for example
(If possible, check the dimensions of the toolâs hook - or nose - to fit the slot of the big groove nut.)
http://global.rakuten.com/en/store/monju/item/ea613xb-2/
http://www.steritool.com/tools/Adj_hook_spanner.htm
http://www.mscdirect.co.uk/ANM-50060C/SEARCH:CATEGORY/product.html
http://de.farnell.com/wixroyd/9515-w061/hook-spanner-pin-hinged-35-60/dp/1379068
http://www.usag.it/catalog/en/products/details/886/282/Hook_wrenches_with_square_pin#
http://shop.spiral.at/data/Katalogseiten/I-019.pdf
http://www.rs-werkzeuge.de/Hakenschluessel
Hopefully you could find more info with the links above,
these hook keys are also used for some motorcycles - should be available at the tool suppliers of workshops.
âŚand did you already ask Strida Hong Kong?
G.U.M.