Author Topic: Should I be concerned or just ride it?  (Read 477 times)

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Offline JDrider

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Should I be concerned or just ride it?
« on: September 06, 2023, 10:18:41 AM »
1975 cb550k1
When I start the bike cold, I turn in the the main idle screw a couple turns.
Starts up nice and easy, but after 10 seconds it surges up 2500rpms and then i back off the idle screw
and it brings it down. After it warms up a bit the idle will climb a little higher and then i back off the idle screw and get it at perfect idle.
It rides fine and doesn't surge anymore once warmed up.
JD
1975 CB550K1

Offline Don R

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Re: Should I be concerned or just ride it?
« Reply #1 on: September 06, 2023, 10:22:38 AM »
 It could be a plug wet fouling and then picking back up. Does it want choke?
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Offline JDrider

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Re: Should I be concerned or just ride it?
« Reply #2 on: September 06, 2023, 10:24:24 AM »
choke is fully on when starting, but i usually turn it to half quickly to get it started.
JD
1975 CB550K1

Offline calj737

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Re: Should I be concerned or just ride it?
« Reply #3 on: September 06, 2023, 10:41:34 AM »
Properly adjusted carbs do NOT need the idle screw tampered with for start-up or take-off.

Set the choke and start the bike, move to 1/2, take off. Give it 10-30 seconds and open the choke fully. Ride on. If you have surging RPMs or a climbing/falling idle, your carbs are not setup. Pure and simple.
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Offline seanbarney41

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Re: Should I be concerned or just ride it?
« Reply #4 on: September 06, 2023, 12:06:23 PM »
Calj +1  Set the idle speed when bke is fully warm and then leave it alone.  May have to use some throttle when starting and idling until the bike is warmed up.  These are not fuel injected.
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Offline Deltarider

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Re: Should I be concerned or just ride it?
« Reply #5 on: September 06, 2023, 01:03:52 PM »
Read the CB550 Owner's Manual p. 28 paragraph 6. https://www.honda4fun.com/dwnload/Owners-Manual/CB550-73-Owners-Manual.pdf Some choose to twist the throttle grip to maintain 2000 RPM, others prefer the idle knob. Has nothing to do with 'properly adjusted carbs', but with preference.
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Offline Don R

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Re: Should I be concerned or just ride it?
« Reply #6 on: September 06, 2023, 01:11:29 PM »
  Most often the answer is ride it until you get to know it better. IMHO.
  My GL1000 told me it hates higher octane fuel unless it's airplane gas or left over race gas. It will spit premium pump gas back out the carbs. 
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
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Offline Stev-o

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Re: Should I be concerned or just ride it?
« Reply #7 on: September 07, 2023, 07:24:06 AM »
When I start the bike cold, I turn in the the main idle screw a couple turns.

Will it start up if you dont turn up the idle?  My 550 does not like throttle until she fires
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Offline JDrider

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Re: Should I be concerned or just ride it?
« Reply #8 on: September 07, 2023, 08:39:08 AM »
It needs it turned up a bit to start easier
JD
1975 CB550K1

Online bryanj

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Re: Should I be concerned or just ride it?
« Reply #9 on: September 07, 2023, 09:13:51 AM »
You are way overthinking this, back in the British bike days you got ready, got on the bike, started it and drove off then when comming to a stop if not fully warm either blipped the throttle or as it used to called "hung the slide" meaning holding the twistgip open a bit to raise tickover
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Offline dave500

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Re: Should I be concerned or just ride it?
« Reply #10 on: September 09, 2023, 12:20:26 AM »
yeah like old cars with manual choke,some take a knack to operate till fully warm,a lost art now with injection?(twist key and it idles),ive always tuned and set engines when fully hot and ridden/driven,how they behave when cold so be it.

Offline Deltarider

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Re: Should I be concerned or just ride it?
« Reply #11 on: September 09, 2023, 02:17:23 AM »
[,,,] ive always tuned and set engines when fully hot and ridden/driven,how they behave when cold so be it.
                                                                                                                          This ^.
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