Author Topic: 1978 CB550 K3 "running" restoration  (Read 11887 times)

Offline SPR

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Re: 1978 CB550 K3 "running" restoration
« Reply #135 on: May 31, 2020, 01:37:07 PM »
Another day another go !!

The aux tank arrived so connected everything up again with the tank in place to give me longer to get the carbs balanced

I just can't believe how fiddly these are to get close ... add to that an idle screw that is so sensitive .... I struggled to be honest

Eventually I think I've got them pretty much within one mark of each other on the gauge and idling at 1100 rpm

Are the earlier carbs this bad - or is that why people tend to change them ?

Cheers

Simon

 

Offline K2-K6

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Re: 1978 CB550 K3 "running" restoration
« Reply #136 on: May 31, 2020, 05:01:00 PM »
To clarify sequencing,  vacuum balance to within 1.6 inch Hg ( 40 mm) then leave the  vacuum adjustment alone.  In other words slides are in spec of Honda manual.

Then use the idle screws to refine the combustion of each cylinder at tickover,  you don't need the gauges fitted for this but use rev counter to observe the effects each cylinder has.

Do you want a photo of Honda manual that describes this element?

Offline SPR

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Re: 1978 CB550 K3 "running" restoration
« Reply #137 on: May 31, 2020, 05:10:21 PM »
To clarify sequencing,  vacuum balance to within 1.6 inch Hg ( 40 mm) then leave the  vacuum adjustment alone.  In other words slides are in spec of Honda manual.

Then use the idle screws to refine the combustion of each cylinder at tickover,  you don't need the gauges fitted for this but use rev counter to observe the effects each cylinder has.

Do you want a photo of Honda manual that describes this element?

I've only one large idle screw ... are you referring to what I call the mixture screw ? I've been tweaking these slightly to get the best overall running

Offline Bryanj

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Re: 1978 CB550 K3 "running" restoration
« Reply #138 on: May 31, 2020, 05:27:41 PM »
The mixture screws stick downwards at manifold side of carb and have a spring , tiny washer and tiny O ring on them. All those little bits are needed and must not be doubled up

Offline K2-K6

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Re: 1978 CB550 K3 "running" restoration
« Reply #139 on: May 31, 2020, 05:28:20 PM »
Yes,  talking at crossed subject there.

The big, single screw that sets the engine's speed at tick over and lifts all carbs together is not the one I mean for idle mixture adjustment.

The mixture screws are the ones in the routine,  after getting slides to parity with  vac gauges, these refine each cylinder to effectively get each one running with the same combustion energy to smooth out crank speed fluctuations.  This to make them run like a swiss watch.

Offline SPR

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Re: 1978 CB550 K3 "running" restoration
« Reply #140 on: May 31, 2020, 05:55:22 PM »
Thanks guys .... yep all correctly assembled and tweaked so hopefully done for now !!

Offline SteveD CB500K0

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Re: 1978 CB550 K3 "running" restoration
« Reply #141 on: May 31, 2020, 06:33:31 PM »
Have you ever heard one running like a Swiss watch?




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Offline SPR

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Re: 1978 CB550 K3 "running" restoration
« Reply #142 on: May 31, 2020, 07:10:00 PM »
Have you ever heard one running like a Swiss watch?




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Sadly not for nearly 40 years

Hopefully I can keep on with this and get a little closer :)

Offline K2-K6

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Re: 1978 CB550 K3 "running" restoration
« Reply #143 on: May 31, 2020, 07:28:09 PM »
Have you ever heard one running like a Swiss watch?




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Ok, I'll give you that one Steve.  Maybe more like a contemporary from the same nation and era.

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How about a Seiko 6139 movement from early seventies.


Offline SteveD CB500K0

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Re: 1978 CB550 K3 "running" restoration
« Reply #144 on: May 31, 2020, 07:32:43 PM »
It’s all relative.

Compared to what else was around at the time, they did run like Swiss watches.

I actually have a Swiss watch.

But it’s electric




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Offline SPR

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Re: 1978 CB550 K3 "running" restoration
« Reply #145 on: June 01, 2020, 02:35:51 PM »
Well touch wood it seems to be running very well ... nice bimble out round Bakewell / Matlock and all was good in the world :)

https://www.youtube.com/watch?v=8oSFa-YgHDM

Offline Rozabikes Tim

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Re: 1978 CB550 K3 "running" restoration
« Reply #146 on: June 01, 2020, 03:27:06 PM »
Well touch wood it seems to be running very well ... nice bimble out round Bakewell / Matlock and all was good in the world :)

https://www.youtube.com/watch?v=8oSFa-YgHDM
Simon, when all restrictions are lifted call in next time you are in Bakewell and show us your good work. Our shop is still closed but when open again it will be good to see the shiney steed!
One day I'll have the time to restore it, not just talk and dream....

Offline Rozabikes Tim

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Re: 1978 CB550 K3 "running" restoration
« Reply #147 on: June 01, 2020, 03:32:56 PM »
Our shop is called Fabric and Furnishing Solutions. Last but one shop on the right if you take the A6 south towards Matlock.
One day I'll have the time to restore it, not just talk and dream....

Offline SPR

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Re: 1978 CB550 K3 "running" restoration
« Reply #148 on: June 01, 2020, 04:57:38 PM »
Well touch wood it seems to be running very well ... nice bimble out round Bakewell / Matlock and all was good in the world :)

https://www.youtube.com/watch?v=8oSFa-YgHDM
Simon, when all restrictions are lifted call in next time you are in Bakewell and show us your good work. Our shop is still closed but when open again it will be good to see the shiney steed!

I certainly will !!

Offline Bryanj

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Re: 1978 CB550 K3 "running" restoration
« Reply #149 on: June 01, 2020, 04:59:18 PM »
Better not let my wife rad this, her fabric stash is nearly as big as my bike stash!!!

 

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