Topic: Best way to warm up my cb500?

[markiemark]

Hi all,

Noob here.  I just got a 73 cb500, it seems to be in really good condition.  Wondering what is the best way to start and warm up the bike?  I live in sunny southern CA so the weather is usually warm.  I've been putting the choke on, (or closing it? or whatever the cold start procedure in the manual says!) and starting her up. 

My question is, should the bike be able to idle on its own with the choke in the cold start procedure?  Or is it necessary to open it up so it can hold the idle?  The bike will die if I don't open it up.

So I've been starting it, holding the throttle slightly open, giving it a couple revs, then opening the choke.  After this it usually idles at about 1000-1200 rpm. 

Sometimes though, like this morning, (It was a bit cold, maybe 60 degrees?) I had it started and it was idling for about 2 minutes, then it just died.  I started it up again and kept it revved a bit more, holding throttle for a few seconds so the tach showed 2-3k rpm, then letting it catch the idle around 1200.  Then it was fine.  Is that weird that it died after 2 min? 

Basically, what's the best cold starting procedure?  Do these older bikes need to be warmed up for 5-10 minutes before taking off on a ride?

Thanks

[domer]

these suckers are cold blooded, that being said mine doesn't like to idle below 1500 (same bike, probably not as nice as yours....) but ya it can take 10 min to warm up on a cold day. i only need to use the choke if its been a couple days since shes ran. after she starts i adjust the throttle control thumb screw (under tank opposite of petcock, big thumb screw, cant miss it) till it sits at 2000-2500 rpm. then light smoke (after its verified the carbs are holding gas ) finish smoke hop on bike and adjust the idle at which ever stop sign the idle sounds too high at. but that's just me, I'm kinda weird to begin with...

[Greggo]

I can't really tell you the best way to do it, but the way I warm up my 500 is by riding it.  I start her up, which almost always requires some choke.  I only use the choke to fire the bike up, like maybe five seconds...not to help warm up.  I turn my idle screw in a twist, and after about 15-20 seconds I take off.  I adjust my idle screw out after a few miles, and...That's it!

Some people may think that's barbaric, but I've found that she runs better than if I would sit there warming up for a few minutes.

[IndyFour]

I can't really tell you the best way to do it, but the way I warm up my 500 is by riding it.  I start her up, which almost always requires some choke.  I only use the choke to fire the bike up, like maybe five seconds...not to help warm up.  I turn my idle screw in a twist, and after about 15-20 seconds I take off.  I adjust my idle screw out after a few miles, and...That's it!

Some people may think that's barbaric, but I've found that she runs better than if I would sit there warming up for a few minutes.

That's my warm-up procedure as well...with the exception of turning the idle screw.  I suite up first before starting her up so that my hands are free to hold the throttle to keep idle as I take off.....riding gently.  By the time I'm out of the neighborhood and on a main street, she's purring.

[TwoTired]

The early bikes had a friction adjust on the bottom of throttle grip.  Tighten that up and it'll stay where you set it for a stationary run.

But, I don't do a warm up.  Suit up, get o,n start with choke and nudge it a bit so it will still make some power.  While riding, your hand is on the throttle, so who needs to futz with the idle knob?  Anyway, each block or so while riding, reach down with your left hand and nudge a bit more choke off, until it is all off.  The engine is at operating temp and idles in the same position/speed that the idle was set for the last time it was at operating temp.

Cheers,

[betterthanurs916]

This is my warm-up procedure

Honda Six

[Deltarider]

500's and later 550's  are treated differently.
Choke of the 500 is ment to use shortly. I open the chokevalves again immediately after starting. Either I keep rpm at 2000 by hand or I have set the big idle knob previously.
At the next trafficlights I either keep the engine from stalling by playing the throttle grip or I gradually turn back the big idle knob. But you don't ride the 500 with closed choke, not even partially. If you have to, it indicates carbs are set to lean.
550's K3 and K4 (and 500K3!) are different with their leaner PDcarbs and they have a cam.

[Hush]

Mine's a 650 but still cold blooded, full choke, 3 twists of the throttle to squirt the accelerator pump (you aint got one  ) fire her up, adjust idle set screw and go get dressed.
By the time I get back outside she is screaming at about 4k and it's time to give the neighbours some peace by backing off the idle screw (I know this might sound a bit extreme but for some reason I have yet to cure, my bike only starts on 3 and the forth only joins in once it's warmed up?) and then I'm good to go.
When you see James Bond steal/borrow some for bystander's bike/boat in the 007 movies he never has to warm them up eh!

[dave500]

yeah im with delta,,i start mine and hold a slightly fast idle for a second and back of the choke almost instantly,then use the throttle lock to hold a smooth idle as i gear up,never let them idle sluggishly cold,this can foul plugs and wash the cylinder walls with unburnt petrol causing wear as the oil is washed of the walls,try and open the choke as soon as the engine will handle it and hold a slightly faster idle somehow if your lock is missing,,never thrash your engine cold,,if you always have frozen clutch plates and a stall happens when first gear is selected,,try holding in the clutch lever in neutral,,,then with the ignition off try and kick the bike over two or three times,,this will break the clutch loose,youll feel suddenly no drive through the kick arm untill you release the clutch again,you will be able to engage first gear with no crunch/lurch or stalling.

[wardenerd]

Turn on gas. roll out of the garage do not wake the wife and college kids.  At bottom of drive make sure gas is on.  apply full choke. check neutral and kill switch.  By now gas is flowing. Hit starter when she fires ( immediately) hold gas open enough to run but not enough to wake the neighbors. Ride off and go to end of street 30 sec cut choke to half ride 3 minutes kill choke.  Runs cold but the 650 is even colder running but has a better choke.

if the 550 sits three days you have to let the gas get to the carbs again before trying to start the biatch.

[jvandyke]

Turn on gas. roll out of the garage do not wake the wife and college kids.  At bottom of drive make sure gas is on.  apply full choke. check neutral and kill switch.  By now gas is flowing. Hit starter when she fires ( immediately) hold gas open enough to run but not enough to wake the neighbors. Ride off and go to end of street 30 sec cut choke to half ride 3 minutes kill choke.  Runs cold but the 650 is even colder running but has a better choke.

if the 550 sits three days you have to let the gas get to the carbs again before trying to start the biatch.

This is my method as well although lately I've been turning the idle thumb screw in a good full turn before I even fire it off then twist a bit either way to hold a high idle.  I turn the idle back down at the first or second stop and I usually get the choke fully off after a mile or so.  The bike will remind me pretty early on to reset the idle as engine braking is drastically reduced with a high idle, not to mention being a stop with a 2500rpm idle.  There is a definate procedure but each bike (even the same type with same carbs and jetting) is different it seems.

[Bankerdanny]

I'm with the get moving as soon as possible crowd. Placing a load on the engine warms it up faster. If temps are above 60 you really shouldn't need the choke for more than a couple blocks.

[markiemark]

Great information, guys.  Thanks.  As for those that fiddle with the idle switch before starting, the manual says only to adjust idle screw when engine is warmed up.  Not sure if following the manual is always a must or if I need to learn to bend the rules a bit.  Just wanted to mention it. 

As for messing with the choke, i.e.  slowly opening it every few blocks or so til its fully open to warm it up, are you constantly having to rev the engine so it doesn't stall on you(at a light or stop sign, for example) until it is open, or does the bike idle with the choke half open just fine?

[jkminer]

On my K0 500 I put the choke full on, and if she's been run within 2 weeks, starts on the first kick. Within 5 seconds choke full off, and I'm running down the road. She behaves very well, and only think's about stalling,(just need to keep hand on throttle) at a stop about 1/4 mile from my house, and then no more problems.

[Spanner 1]

I dont even start my bike until all my gear is on and I'm ready to go, sitting on the bike. Start with full choke and ride away immediatly opening the choke in increments over the first mile. If your bike wont idle after 1/2 mile of riding ( warm-up ) then a service is needed IMO. ! I really dont like to start the bike and let it fast idle to warm-up without airflow and load on the motor, 'prolly just oldschool, but hey 

[jvandyke]

Great information, guys.  Thanks.  As for those that fiddle with the idle switch before starting, the manual says only to adjust idle screw when engine is warmed up.  Not sure if following the manual is always a must or if I need to learn to bend the rules a bit.  Just wanted to mention it. 

As for messing with the choke, i.e.  slowly opening it every few blocks or so til its fully open to warm it up, are you constantly having to rev the engine so it doesn't stall on you(at a light or stop sign, for example) until it is open, or does the bike idle with the choke half open just fine?

Maybe the term "throttle stop adjuster" is more appropriate then "idle screw".  The big knurled "wheel" on the carb assembly where the throttle cables attach.  It's easy to reach for (once you've trained your hand a bit) and easy to spin while seated.  The point of "resetting throttle stop" (IE: idle adjustment) is to avoid stalls.  Stalls suck.  And yes, bend the rules all you want!  Just this morning at breakfast we were talking about Harley dudes who constantly blip the throttle at lights, are they trying to maintain that WAY TOO low lumpy idle that sounds cool?  Trying to broadcast their coolness in general via occasional pipe snort?  Or are their bikes just tuned so crappy that they can't idle?  Probably a mix of the first two reasons but to my ear, if you can't pull up to a stop with a smooth idling bike, you're on a lousy bike and/or you're kinda dumb.  IMHO.
And I try to get the choke off ASAP but my 500 is pretty cold blooded too and it likes some choke for a mile or two.

So, yeah, I twist the "throttle stop" clockwise 1/2 to 3/4 turn (since it was left at "warm idle setting" after last ride) Full choke, fire it up, twist the screw to hold at 1500 or so, back off the choke a little, tighten up the chin strap, take  off and after a mile or so start tweaking back the choke and idle when convenient.  But that's MY 500 with MY carbs and YMMV for sure.

[TwoTired]

As for messing with the choke, i.e.  slowly opening it every few blocks or so til its fully open to warm it up, are you constantly having to rev the engine so it doesn't stall on you(at a light or stop sign, for example) until it is open, or does the bike idle with the choke half open just fine?

No, you just hold the throttle open manually to up the idle to about 1500-1700.  Its the same thing the idle stop thumbscrew does...without the futzing/distraction.
Some carbs have a fast idle cam coupled to the choke.  Yours doesn't have that.  It relies on the bike computer to raise the idle.  You'll find that computer about 2 feet above the seat, often encased in a plastic shield.

Cheers,

[wardenerd]

one more thing about chokes.  If you are on full choke on a dirt road and close the choke while moving the bike will accelerate quickly and catch you by surprise and you will be hanging on for dear life for a few seconds.  Careful careful

[jkminer]

one more thing about chokes.  If you are on full choke on a dirt road and close the choke while moving the bike will accelerate quickly and catch you by surprise and you will be hanging on for dear life for a few seconds.  Careful careful

That's why I switch my choke to full off before I move (I live on a gravel road)

[jvandyke]

As for messing with the choke, i.e.  slowly opening it every few blocks or so til its fully open to warm it up, are you constantly having to rev the engine so it doesn't stall on you(at a light or stop sign, for example) until it is open, or does the bike idle with the choke half open just fine?

No, you just hold the throttle open manually to up the idle to about 1500-1700.  Its the same thing the idle stop thumbscrew does...without the futzing/distraction.
Some carbs have a fast idle cam coupled to the choke.  Yours doesn't have that.  It relies on the bike computer to raise the idle.  You'll find that computer about 2 feet above the seat, often encased in a plastic shield.

Cheers,

So really you mean yes, you have to artificially throttle up to maintain idle (rev).  I think it's much easier to twist the knob a half turn and have to "do it myself".  Same difference in the end I guess.

[TwoTired]

As for messing with the choke, i.e.  slowly opening it every few blocks or so til its fully open to warm it up, are you constantly having to rev the engine so it doesn't stall on you(at a light or stop sign, for example) until it is open, or does the bike idle with the choke half open just fine?

No, you just hold the throttle open manually to up the idle to about 1500-1700.  Its the same thing the idle stop thumbscrew does...without the futzing/distraction.
Some carbs have a fast idle cam coupled to the choke.  Yours doesn't have that.  It relies on the bike computer to raise the idle.  You'll find that computer about 2 feet above the seat, often encased in a plastic shield.

Cheers,

So really you mean yes, you have to artificially throttle up to maintain idle (rev).  I think it's much easier to twist the knob a half turn and have to "do it myself".  Same difference in the end I guess.

I meant no.
He asked if you have to constantly blip the throttle to keep it running.  No, just hold it a bit open.  Without the distraction of twiddling with a knob at least twice every time you run the bike.

[jvandyke]

well, he asked if you have to rev the engine, which would be yes, do you have to rev it high and let it fall, blip it up and down, no, not if you're good at guessing where that 1500rpm spot is gunna be as you slow up, gotcha, I understand what you're say'n.
I actually just started using the throttle stop screw as temp high idle and I like it instead of trying to hold a high idle myself amidst all the other duties of starting off on a ride.  I say fool around with various methods and see what ya l like.