First Start Highs and Low!

[deltarider]

You need to keep some choke on for a couple of minutes until the engine warms up enough to run without it. It will stall without any choke when cold. Gradually reduce the choke to keep the revs from rising as the engine warms.

This is only true for models that have the PD carbs. The older models with 069A carbs are not supposed to start riding with the chokes partially closed. A raised idle enough. That's why the K3 had the choke knob positioned at the handlebar in the view of the rider. Earlier models had a choke lever on the left side of the carbs and Honda did not intend you to take your left hand from the handlebar to feel around for and fiddle with a lever somewhere below. Honda's idea for safety first and hence it is in the starting procedure in the Owner's Manual.

[taysidedragon]

You need to keep some choke on for a couple of minutes until the engine warms up enough to run without it. It will stall without any choke when cold. Gradually reduce the choke to keep the revs from rising as the engine warms.

This is only true for models that have the PD carbs. The older models with 069A carbs are not supposed to start riding with the chokes partially closed. A raised idle enough. That's why the K3 had the choke knob positioned at the handlebar in the view of the rider. Earlier models had a choke lever on the left side of the carbs and Honda did not intend you to take your left hand from the handlebar to feel around for and fiddle with a lever somewhere below. Honda's idea for safety first and hence it is in the starting procedure in the Owner's Manual.

The choke is not an on/off switch.
The fuel tap is down on the left hand side of my bike and I  have no problem turning it to reserve while riding.

[deltarider]

You need to keep some choke on for a couple of minutes until the engine warms up enough to run without it. It will stall without any choke when cold. Gradually reduce the choke to keep the revs from rising as the engine warms.

This is only true for models that have the PD carbs. The older models with 069A carbs are not supposed to start riding with the chokes partially closed. A raised idle enough. That's why the K3 had the choke knob positioned at the handlebar in the view of the rider. Earlier models had a choke lever on the left side of the carbs and Honda did not intend you to take your left hand from the handlebar to feel around for and fiddle with a lever somewhere below. Honda's idea for safety first and hence it is in the starting procedure in the Owner's Manual.

The choke is not an on/off switch.

But... it almost is. On the oldstyle carbs chokes can gradually be opened within 8 seconds. Has to do with the settings of oldstyle carbs, which were set quite rich. You need a slightly raised idle though as suggested by the Owner's Manual. If you need the chokes for longer, it indicates your carbs are set too lean. Sorry, but this has been my experience with these models over 46 years. I've helped with quite a few bikes where the owner had been tempted to set the airscrews too lean, because they liked to have the engine purr like a kitten. The PD carbs are a different category.

The fuel tap is down on the left hand side of my bike and I  have no problem turning it to reserve while riding.

Your choice. Some choose to switch to reserve prior to taking of. Both hands at the handlebars at all times is the safest strategy. Honda must have realised this so headlight switches positioned on top of the bucket on older Honda's have been abandoned. Far out the most dangerous a rider can do, is adjusting the mirrors whilst riding. Don't!

[florence]

On my 500, it has always been full choke to start from cold.  One kick of the starter, away it goes and then after a few seconds with the choke in this position, the revs drop slightly, then flip to fully open and it's ready to go.

[Oddjob]

You seem to forget that the K0 version had different switchgear DR. They got slated in the UK bike mags for all the lights going out accidentally when switching from high to low so Honda altered that by fitting a separate light switch and calling it the K1. To operate that light switch needed you to remove your left hand off the bars, now don’t say ride with the lights on even during daylight as that just wasn’t done back then, in fact I’m fairly sure the police would have pulled you over and other motorists would have been flashing you to let you know they were on back then.

We also would NEVER had switched to reserve before it started hicupping as that was your warning to start looking for somewhere to fill up. Never run out of fuel on a bike with reserve but done it a couple of times with ones with a fuel gauge, even one that flashed to let you know.

As for choke, full choke to start in the winter or early morning and then half choke till the end of the street before dumping it off as I rode. Quite a few one armed riders around, you are safer with two hands but it’s not essential all the time. Ever scratched yourself riding? Or altered your visor? Or even just wiped water off your visor so you can see? All done one handed.

[deltarider]

Oddjob, all the above, is what I also do occasionally. However every oldstyle CB500 has a carb setting that you can start riding with the chokeflaps fully reopened. Just keep a slightly raised idle for the first km or 2. If you need the choke in combination with a raised idle riding it's indication you've been tempted to turn out the airscrews too far. Period. Too far can be even a small increment of 1/8 of a turn!

[Skoti]

Hold on tight folks for yet another long thread.

Here we go again with more on the air screw myth...

[Neilw]

Just an Update - and honestly you just can't make this up!

The overspill has gone, as far as i can tell from carb 2. UI dropped the height of the external fuel tank and got set to go.

Tried to start the bike, but it just wouldn't fire. Cleaned the plugs and went to go again, but the Battery is dead!. So I had to order a charger and let it charge overnight.

Full of hope this morning, I reinstalled battery and fired her up, of rather it didn't want to fire. Popped plug 4 out and there was no spark, tried 3 and there was. put 3 back, started the bike and it sort of jumped into life briefly before dying, now no spark there either.

I've spent the morning testing and it seems it could be the coils, i'm not getting the readings the videos say I should, but as the language is not consistent across the videos i don't 100% know if i'm checking the right wires with the multi meter at the coil. Basically, I get 0 when connecting the MM to the yellow and black/white wire coming out of the coil and the same for the Blue - Black/White combination. Is it possible for both Coils to fail at the same time?

So i can't even get the bike started to see if the carbs are any better! FML lol!
 

[deltarider]

Hold on tight folks for yet another long thread.

Here we go again with more on the air screw myth...

That's not very friendly of you, Skoti. Please read p.29 in: https://www.honda4fun.com/dwnload/Owners-Manual/CB500-K1-Owners-Manual.pdf
I've cured quite a few bikes, by bringing the idle to 4-4,5% CO again. That's about mid range on a CO-tester of that era.
What I presume - but it's only a presumption - is that owners, today oldtimers themselves, are more interested in a nicely purring idling than in good driveability. Maybe the only ride they do is: bring their bike on a trailer to a show, let it idle, harvest compliments from bystanders on how well it runs and then return home, bike on the trailer again.
Anyone who doubt my posts, can try it out for himself. After extensive testing, my airscrews differ in position, but they average 1¹/₁₆ turn out. That's damned near Honda's 1 turn out ⁺/_- ¹/₈, dont you think? If I go leaner with those air screws, I'll have whitish spark plug noses at 3000-3500 rpm in 2nd and 3rd gear. If I turn the airscrews a tad in again, all is well again. Can you explain me that? Please refrain from negativity, Skoti. Me thinks, we have had enough of that.

[Neilw]

Just an Update - and honestly you just can't make this up!

The overspill has gone, as far as i can tell from carb 2. UI dropped the height of the external fuel tank and got set to go.

Tried to start the bike, but it just wouldn't fire. Cleaned the plugs and went to go again, but the Battery is dead!. So I had to order a charger and let it charge overnight.

Full of hope this morning, I reinstalled battery and fired her up, of rather it didn't want to fire. Popped plug 4 out and there was no spark, tried 3 and there was. put 3 back, started the bike and it sort of jumped into life briefly before dying, now no spark there either.

I've spent the morning testing and it seems it could be the coils, i'm not getting the readings the videos say I should, but as the language is not consistent across the videos i don't 100% know if i'm checking the right wires with the multi meter at the coil. Basically, I get 0 when connecting the MM to the yellow and black/white wire coming out of the coil and the same for the Blue - Black/White combination. Is it possible for both Coils to fail at the same time?

So i can't even get the bike started to see if the carbs are any better! FML lol!

Confirmed I have cooked the Primary circuit, most likely becasue i left the key on while diagnosing the starting issues. New ones on order,

[McCabe-Thiele (Ted)]

I don't know how long you have left the ignition on for, I'm not 100% certain but it's very unlikely that both coils would  be cooked, only the one where the points were closed possibly.

In the past I've left the ignition on overnight (on a car), the battery was flat, the coil body was hot, when it all cooled down it was OK again.

[Neilw]

I don't know how long you have left the ignition on for, I'm not 100% certain but it's very unlikely that both coils would  be cooked, only the one where the points were closed possibly.

In the past I've left the ignition on overnight (on a car), the battery was flat, the coil body was hot, when it all cooled down it was OK again.

It's my best guess, as the regulator is within spec, so it shouldn't have caused the issue. I guess 50-year-old electrics are susceptible; I had to change the solenoid out, as that was also bad.

[McCabe-Thiele (Ted)]

As a general rule it's moving parts such as solenoids, ignition switches, indicator relays that are common failures.
If the original coills fail it's usually just the HT leads themselves that cause problems.

[Oddjob]

It’s well known if you leave the ignition on and the coils energised they are prone to burning out Ted. It’s not common as it requires some time to happen but it does happen now and then. Other than the leads they are almost indestructible.