Topic: Ignition barrel - power cutting out - any tips?

[1977_cb550k]

I had the harness/ignition barrel repaired twice and it’s still cutting out all power intermittently. Which is mighty dangerous as everything cuts out, including the brake lights.  It only holds electrical connection when I strap a cable tie around it and tie it to the handle bar, holding the harness firm. 

I think I need a new ignition key set. Any tips on good aftermarket ignition key sets, or is there a fix for this issue? I hear it’s semi common.

1977 honda cb550 k3.
Honda part number;
35010377007P

Thanks.

[RAFster122s]

Ignition barrel??? Huh? What is this part you refer to? The ignition switch is attached to the lock? Does your ignition switch have an issue?

[1977_cb550k]

Yes, sorry - ignition switch.

[RAFster122s]

Emgo switches can be bought, but probably would pay you to use the switch as a relay to drive a power relay so that the switch is only serving to switch the relay, the relay contacts can handle the power better than many of the Emgo switches unless they changed things. The contacts are not known to hold up for a long time.
Alternative is to buy the Honda OEM switch set that has the steering lock and the seat lock as well.

Have you disassembled the switch to clean the contacts? Often the white plastic cover that secures the switch to the lock has a tab break off and then the switch no longer is held securely causing loss of contact. Emgo has a replacement part that I think works for the original lock assembly. If it fits that is likely your solution...

David

[newday777]

South Sound Honda shows different parts numbers than you posted. Where did you get the part number you posted?
Depending on your vin numbers, there are 2 different numbers. 35010-393-772(not available from Honda)and 35010-377-007(doesn't show not available). They don't show the 35010377007P you posted. (Just a FYI,  the dashes need to be in the part numbers for searches should be 35010-377-007P)

There is one of each (NOS)I saw just now doing part number search on ebay

Here is a NOS available in Oregon (USA) on ebay
35010-393-772

https://www.ebay.com/itm/145049578343?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=f3vh0fq7sbk&sssrc=4429486&ssuid=okhTUXaIQdO&widget_ver=artemis&media=COPY

JTMarks (great NOS parts supplier on ebay) has the 35010-377-007.

https://www.ebay.com/itm/324178697095?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=_Mr7oZObTey&sssrc=4429486&ssuid=okhTUXaIQdO&widget_ver=artemis&media=COPY

Let us know how you make out on this.

[newday777]

I just looked at CMS (Nederland) and they show the 35010377007P as an alternative part ie aftermarket parts, usually not a good choice as early failure rates in the aftermarket ignition switches.
They also show the 35010-377-007(2 available from them)
Their site doesn't have a share button so if you haven't seen their site search CMS on the web.

[Deltarider]

[...] and they show the 35010377007P as an alternative part ie aftermarket parts, usually not a good choice as early failure rates in the aftermarket ignition switches.[...]

I would't use the word 'usually'. Not before we know more. A couple of years ago I had to replace my OEM (oldstyle!) and I choose the imitation CMS offers. So far no problem at all. Partnumber: 35100-341-700P*
I suspect the idiotic wiring for the US models is the real culprit. Every time, you turn the key to ON, the headlamp comes on. That's a lot of amps at once and I suspect it's the sparking that goes with it, eventually wears the IGN switch prematurely.
* https://www.cmsnl.com/products/switch-assycomb-non-oe_35100341700p/

[BenelliSEI]

Despite all I’ve read here, I used an EMGO switch on my cb750K8 several years ago (far from home, original fell apart). It’s still in there and working well.

[1977_cb550k]

Thanks Stu, very helpful!
Is the gas tank key lock easy to swap out?

[bryanj]

Usually the gas tank lock works with any key

[1977_cb550k]

Ah…that explains the aftermarket sets not including the gas tank lock..thanks.

[pekingduck]

There are two halves to the fork lock style ignition switches with the key switch bolted on the top crown.  The upper half is all mechanical - if the key turns and locks and comes out normally, the mechanical part is fine.  This is good because your seat lock/helmet lock, and on CB650 models with the locking removable gas caps, are all keyed the same, (as on CX500, CBX, DOHC fours, etc).

The bottom part is plastic, and has the switching mechanism and harness connector.  These get loose and worn over time.  The actual switch contacts are layered inside - the 2 balls visible serve as switch position detents only. 

The wiring harness connector is getting tugged constantly, as the switch/steering rotate and the harness wants to stay put, and is the cause of the failure.  Honda realized this and made separate kits available with these parts, but they are long discontinued.  (You can see it on the CBX parts catalog ignition switch/top clamp page). 

Fortunately, they are available for well less than $25 on eBay or Amazon under "Honda ignition switch repair kit".  I would recommend staying with the EMGO brand, as their quality is very good.

[1977_cb550k]

Does anyone know if this CB400f switch is compatible with the CB550k3?
It looks an exact match?
https://www.yamiya750.com/index.php?main_page=product_info&products_id=3105

[rotortiller]

Sometimes the copper rivets holding the switch contacts loosen off. I have found careful cleaning and a bit of solder wicked in under the rivets to be a cheap and long term solution for that situation. Or this. 

[1977_cb550k]

Thanks @Pekingduck - unfortunately those Emgo repair kits are not available on Amazon or eBay in Australia - so it’s another $50 and 4 weeks wait to get them sent to Sydney!

[pekingduck]

Yes, they are the same ignition switch, although the seat lock may be different. 
That ignition switch, which has 5 pin connectors, fits all of the 1975-1982 fours except 78 and later GL1000 that use 6 pins.

[1977_cb550k]

Thanks everyone for the great advice. Took the ignition switch out and took it apart. The black plastic section with the brass contacts is deteriorating and basically crumbled in my hands! I’ve ordered a new plastic assembly (thanks PekingDuck!). It’s a $10 part that costs $40 to be shipped to Australia 😯but ce la vie.

I’m not very confident mechanically so all your advice and links really helped as always. To the folks who make ‘how to’ videos - thankyou! It’s a huge help.  That’s why I happily contribute $ every month to keep this forum going!