Honda-SOHC

So over the past few months, when time permits, I've been going through my very scabby 750. But once getting it out on the open road, I quickly noticed it lacked a lot of power. Low and mid range seems decent enough, but there doesn't seem to be a lot happening beyond half throttle.

I have 657A carbs, but it came with 130 main jets. I replaced them with stock size 110s (i'm running a stock airbox now) as well as moved the needles to position 4, and that improved things significantly - its not completely stumbling at half throttle any more - it has a little more punch at the top but it still feels very weak. Can't really get over 60mph

Low end punch seems mostly fine - right now I know its not running perfect, i haven't balanced the carbs beyond the best i can do by eye, nor set the idle mixture beyond the stock 1 turn. But as far as i know, that shouldn't affect much once you are deep into the throttle?

I haven't done a compression check - perhaps a big mistake. I don't have a gauge yet, but maybe i should've thought about getting one before spending money on a bike! Though it doesn't seem to gallop, so I'm guessing if its down on compression, they are all roughly equal.

Since last putting the carbs on, the idle has been hunting quite badly, I think I have an intake leak, though the heavy throttle behaviour has been the same before and after this, so I'm not expecting that to be the solution - though of course I need to fix that asap.

I've been through the carbs fairly thoroughly I think, I'm quite sure everything is clear, emulsion tube holes etc.
Tank has been cleaned, and new filter sock over the petcock (I have the threaded on style petcock, took me a while to find the part)
Spark advance is free, so that should be fine. Static timing should be fine, though perhaps I should try and verify with a timing light

Could it simply be that, for whatever reason, stock main jets aren't close enough? Or can anyone think of anything else that might create this sort of behaviour?

Thought i better do the mandatory introduction before i get in trouble.

I'm a fairly new rider, in my 20s (though not for long...), and late 60s/early 70s Honda's are what I see in my head when you picture the word "motorcycle", they are the quintessential, imo.
I have a 1971 CB350 twin, which I adore. Its not perfect, its been poorly painted in the past but its good enough for me.



The K0-K6 CB750 is more or less a dream bike, but I tend to fall on the cheap side so of course I picked up the roughest one available.
I'm afraid to even show it, but here it is, after its maiden test ride a few days ago.



Bought sight unseen from ebay as a non runner, I'm sure some of you have seen it floating around before. Had extended forks, tall bars, strange seat, horrible graphics painted on the side covers, tank smoothed over and painted black, double width chain and sprockets, the works. (I'll be (trying to) sell all of those parts, if anyone wants. The extended forks came with early style lowers, that seem decent)
Also a lot of stuff has been sadly poorly chromed, and the cylinder/heads been painted black. The new seat came with it. I like it, but it seems to sit a little squint, as if it needs some shims or something on the hinges.

My priority is to get it running (check), and road legal (still working on it), on somewhat of a budget if possible! I'll then get the tank/covers/badges done later. Same with the exhaust, and i'd like to get an 18 inch rear wheel too.

Been good fun going through it and getting it to run. The lack of spark was simply dead condensers, crusty points, ignition wire unplugged (security measure?). Carbs were of course all caked in dirt, but once cleaned it fired into life with surprising ease. Needs tuned, but for now my attention has moved towards getting it road worthy.
There were quite a lot of electrical issues, though I think I have everything working now, just missing indicators. Rebuilt the master cylinder and caliper. Forks need doing, and the steering head bearing is as bad as I can imagine one ever getting, was like riding a bike via the arrow keys!

I could go on, but you get the idea. Everything needs going over, and will get done, but over time.

Here's a bonus pic from the sale. The way I see it is I'm saving it... someone had to do it anyway!

Hi all, my USA spec K3 is missing indicators, and I'm struggling to find a set. I believe they are supposed to have two wires, for both indicators and running lights?
I'm not overly sure how single wire ones would work, any advice on that would be handy too.