Honda-SOHC

You look ever so familiar Al, you ever worked in the North West?

No problem, always worth an ask.

The indicators BTW are for the USA market, not sure if your using them on the build but if you are you could consider going back to the UK spec ones, just look at any pic of a UK 550 and you'll see what I mean. The USA market also got a different right hand switchgear, there is no headlight flasher switch like the UK one, it's just a horn button and not a combined flasher/horn combined. You may also find the indicators are running lights, not allowed over here but easy to disconnect.

The grab rail looks wrong, it should be much higher at the back, or it could be the seat is sitting far too high at the back,  tail light bracket was black in the Uk not chrome. None of these is detrimental to the bike, it's just info you may not know.

Any pics of the left side, if it still has the original exhaust that's a BIG bonus and they are rare and expensive to buy.

I have a couple of NOS rear brake levers if yours is damaged or really rusty.

Now that's my idea of a bike, you can keep your CB72 and 160s, the 250K0 was when Honda started to produce proper motorbikes IMO. Lovely.

Looks enough metal on the other spring to make another loop to match the F2 spring Roo. Just find something the right diameter to bend it round.

Not far from me that, I've been past that hundreds of times as well. My daughter will love that.

I’m aware of that but unlike red grease it really doesn’t have much in the way of lubricating factors, in this case red grease is a better answer. Now the bolt holding the brake arm onto the pivot pin is perfect for copperslip.

I was wrong, memory is starting to fail  10 psi for the forks and he says fit 3 washers (but doesn't say how thick they are) in the forks so they effectively preload the springs. So I'd say say 5-10mm of preload. My springs are mismatched in length, so what I'm thinking is to fit the springs etc, no preload at all, place a heavy weight on the top of the fork top, maybe my old vice, measure to see how far it compresses the fork and mark it. Do the other fork and then match the preload so they both compress the same distance. Not sure if that's the correct way but it makes some sort of sense.

Trim those screws into the inlet manifolds, measure the bores of them all and see if they match, if not make them match, smooth out any casting marks, rough spots etc. Should get another 5bhp doing that without affecting engine response.

If you want a little more power, get the cam lobes modified, no more lift, just more duration. So 5 degrees of overlap and 10 degrees of duration. Engine won't be cammy with such a mild mod. Think I have a spare cam so may just try that one.