Brian, do you mean 12mm as second choice? And what material? Ally, stainless, mild?
Hi Geoff
They are cylinder head nuts in an awkward spot hence the need for a torque wrench adapter. The original 13mm nuts are steel I guess as they go rusty. Steel replacements would be fine.
Brian, I've bought special nuts from these people recently and as they manufacture in the UK they may be able to help. You can talk to a real person who will understand what you want.
I searched through all my containers of salvaged stuff last night and can't help but these people I've found very useful for marine grade stainless, so they might be worth a phone call.
http://angliastainless-stanton.co.uk/services
Hope you manage to find what you need.
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The sign on my cabin door said "Not enough bucks stop here".
The nuts need to be torqued down on the cylinder head studs but its impossible to get a socket on them. The wrench I got only does 12mm and 14mm. Can't find a 13mm torque wrench adapter but its gonna be cheaper to change the nuts
I was replacing a head and started to look for different sized nuts when I realised that the standard nuts are actually 12mm after all and my torque wrench adapter fits
This is where the nuts are situated on the TTR head.
Interestingly I did the two nuts up first by sense of feel as I always have done in the past and the torque wrench confirmed I was spot on
Sorry to have troubled folk but I am sure the contacts will come in useful another time