The 500/550 with those carbs need choke on to start but almost immediately back to half after starting and fully off fairly quickly, unless you are trying to ride in sub zero temperatures and i for one am too damned old for that!
The running
now, indicates there's room for improvement.
I see a tube/some tubes (?) near the carbs and breather tube which I cannot identify. What is it/are they for?
Here some tips. Fuellines need to be 5,5mm ID and the length should be 18 and 30cm for the models with the oldstyle petcock and 17 and 28cm for the models that have the newer model petcock. Use the clamp for the fuelline that feeds carb 3 + 4 (see pic). The CB500/550s are very sensitive for correct dimensions and routing of the fuellines. No ups and downs and no extra socalled inline filters, this to avoid nasty surprises which you may encounter even weeks later, when you have already completely forgotten you ever fitted them and are scratching your head in wonder what's wrong! Don't ask me how I know.
Then, the correct starting procedure is well instructed in the Owner's Manual. I've nothing to add to that. Read it and follow it up. For these models it's normal, you need a somewhat raised idle for the first one or two km after you've put the chokelever
fully down. Don't be tempted to ride with the lever halfway. The lever -
not being in the view of the rider! - can make you forget about it. These models were developped with Honda's extreme care for ergonomics. Honda certainly did NOT want you to take your left hand from the handlebar to blindly trying to find and fiddle with the choke lever. Chokes should be fully reopened (lever fully down) before you begin your ride. As these models have a relatively rich idle - certainly in comparison to the later K3 models - a somewhat raised idle is enough for good driveability in the first 1 or 2 kms. So if you need to stop say at a traffic light, just keep the idle somewhat raised. If you would need the chokes partially applied riding the first stretch, it's clear indication the mixture is set too lean. Period. The models with PD carbs is another story. I won't go in to that here.
I'd doublecheck the ignition just to be sure: a correct timing at full advance is paramount. If it's not, don't fidlle with the plates, but first check the breakerpoints gap. Usually a little tweaking there can result in a correct timing. This under the bordercondition that breakerpoints gaps are within spec knowing 0,3-0,4mm or 24,5
o-23
o when measured by a dwellmeter set in the 8 cyl position).
Having the airscrews where you have them now, I'd (re)sinc at ~1200 RPM. If needed you can check the slow circuits of all four by individually turning the airscrew full in, wait 20 seconds and then open 3 turns, wait another 20 seconds. If you hear no change in RPM it's indication something is blocked in the slow circuit, usually a blocked slow jet. Mind you, in this test the change in RPM can be very,
very little. That's good enough. If all slow circuits hve proven functional (clear), readjust the airscrew to where you had it before the check. Repeat the procedure for the next carb. An eventual tweaking of the mixture by the airscrews can be done later. For the synching it plays no role, provided the slow circuit is clear. I've substantiated this extensively here:
https://www.sohc.co.uk/index.php/topic,32847.msg320078.html#msg320078Success!
Show Posts
I don't mind and do not worry about blocked ventilation holes. During hibernation I put some plastic foil in between cap and tank to prevent evaporation.