Little quiz on how well you know the 500K

[Oddjob]

I've worked with Hondas for a long time now and I never noticed this until recently, or I may have noticed it but never really thought about it.

Bolts on Honda engines of the 70s and 80s and maybe even before and since tend to have certain sized heads, 5mm bolts have 8mm heads, 6mm bolts have 10mm heads unless it's after the 250N era when they started to introduce 6mm bolts with 8mm heads, 8mm bolts have 12mm heads, unlike say Yamaha who preferred 13mm heads and 10mm bolts had 14mm heads. I'm sure you all noticed this. Same applies to the nuts used, most are 10mm, 12mm ,14mm or 17mm.

So when I started to dismantle my 500 recently I took only those spanners with me. However I noticed that there is a 13mm headed nut on a Honda that is standard, all the 500s have this nut, there is also a 9mm nut and some 11mm nuts.

So for kudos, and Graham your exempt from this quiz as I'm sure you'll know at least some of them, where EXACTLY are these oddball items, the answer needs to be exact, you can't just say front wheel for instance.

This is just for fun and may just extend your knowledge even further. It may also be true of the 750 and 400 BTW, once the answers are known maybe someone can tell us if that's so.

[Trigger]

There on a part that Honda never assembled  and not made by Honda 

[Oddjob]

There on a part that Honda never assembled  and not made by Honda 

Yeah but that's most of the bike. Honda didn't actually make a lot of the stuff, they subbed it out to other firms.

[matthewmosse]

Lol, on my bikes I doubt many nuts / bolts were original. Battery tray uses 12mm heads. Front engine mounts 13 by the frame? Off the top of my heads that is what I can think of - might not even be right on those. Interesting that this kind of feature might be original as I always assumed it was previous owners fishing whatever suitable bolts out of their parts bins that accounted for the oddball selection of nuts on the odd locations.

[Oddjob]

No, the front engine mount bolts should be 12mm headed, well the ones through the frame anyway, the others are 14mm headed IIRC or are the long bolts using 17mm headed nuts.

Oh and I can guarantee the 13mm headed nuts are still in place as are the 11mm and 9mm nuts.

[mickwinf]

top yolk clamps !!mm?

[Oddjob]

No they are 12mm on the 500 and 10mm on the 550

[Tomb]

Fork bottom wheel spindle clamp nuts?

[Oddjob]

Nope Tomb, standard size nuts on those. Considering the amount of members on here who have worked on this part I'm surprised no one has got it yet, maybe like me they just didn't notice the oddity. The 13mm nut is really prominent, the 9 and 11 however really hide, you can see them but unless you've ever undone them I doubt you'd notice they are different, plus IIRC they are brass nuts not steel.

[Trigger]

I know, I know 

[Nurse Julie]

I know, I know 👋👋👋 We have them on the 400/4's but I think they are classed as caps....not nuts.

[mickwinf]

brass thingies on the carbs?

[Oddjob]

brass thingies on the carbs?

Bingo Mick, and yes Julie I'd have said caps as well but that would have given the game away, you still need a spanner to undo them so I'll call them nuts.

Still got the 9mm and 11mm nuts to find yet, the 9mm is brass or copper, the 11mm are steel.

[Seabeowner]

brass thingies on the carbs?

Beat me to it. Brass nuts on carb opening mechanism. Also there is a 7mm headed bolt under the top caps. Also my 550 has a 13mm nut on  the axle/chain adjustment. (but not my 500s)

[Green1]

Brake bleed niples 11mm