Topic: 78 Honda 550K cuts out/elec. suspect ignition/key

[ugmold]

Hay folks,
Lately my bike has been quitting at odd times, which is getting scary/dangerous. Sometimes if the clutch is out it will jump start itself. If I need to pull off the side of the road it starts right back up. I have cleaned the fuse box well and also the battery connection, but my guess is the ignition key switch. Is there anything to service on this switch? I put a little graphite in and contact cleaner.

Was fine on the ride into work this a.m. ?

Thanks,
-ugmold

[Gordon]

Is the plug on the back of the switch fitting tightly and staying tight?  A loose plug is a common problem.

[TwoTired]

The starter motor is self engaging?
Check the starter pushbutton switch for disintegration.

[ugmold]

I'll check that plug, looked rather busy around the plug, I guess I'll take off the tach and speedo etc, give it a good clean.

TT, not sure what you mean. Button for the starter seems to work fine however.

-ugmold

[ugmold]

Took it apart when I got home from work. Unplugged the connector, hit it with the soft brass brush and some contact cleaner and the connection seems better. Time will tell.

Thanks,

-ug

[bryanj]

Is this the one with the ignition switch between the clocks, if so they are notorious for the contact assembly on the base on the switch playing up and the block connector pulling loose due to tight wire run

[ugmold]

Yes,
It is a white plug with 6 connectors. The plastic connection appeared tight. The contacts a bit oxidized, so I cleaned them up. I don't know if there is any way to clean inside the key cylinder/tumbler that would make a difference, but I sprayed a little contact cleaner and some powdered graphite in there.

Didn't ride to work today, but I guess time will tell if I fixed it.

-Ugmold

[bryanj]

Lubing the tumblers wont affect the electrical part which is a seperate unit clipped to the bottom of the key/steering lock part and was available seperately.

Part number  35101-422-007

[ugmold]

Thanks, looks available too.

Does it pop out of the bottom of the cylinder? I only pulled apart the connector.

-ug

[ugmold]

http://www.motorcycleworld.org/enthusiasts/catalog_item_detail.asp?catalog=4306&levelcode=10292&product=521589&cattype=&ProductCategoryCode=

[Superior Chops]

Just so happens the same thing happened this past Sunday to my kids 78 550. Complete electrical shutdown. It was the ignition switch. Got it home and we took the switch off pulled the bottom part off and managed to get the switch apart and found one of the copper contacts that fit in the white plastic half of the switch was stuck and the spring behind it could not push it against the switch contacts thus no fire. Cleaned up the slots in the plastic and filed the copper contact so it fit a little looser, put it back together and all was fine. I really like these old Honda's. Thanks for the link to the replacement parts, I think I'll pick up one to have for a spare.

[ugmold]

Well the cuttin out is back, so I ordered up a switch.
http://www.outwestmotorcycles.com/


And of course my new oil pan is leaking, ordered a new gasket. Also bought new exhaust stud.


One Step forward, two steps back.

-ug

[Jerry Rxman Griffin aka MuthaF'er]

Does anyone know if that replacement base will work on our 750's? It doesn't cross reference as a match.

[ugmold]

While I was looking it up the references pointed to it being for a GL-Goldwing. It seems to be a common part however and available from many parts places. Prices varied from >$8 to $42.

This morning riding in I noticed a semi hard right turn will kill the bike, must be yanking on the harness. I'm glad the place I ordered the switch from sent it out the same day, don't like riding like this.

-ugmold

[bryanj]

The switch base should fit all of the bikes, originaly there was a 5 contact and a 6 contact but the harness plug was the same for both with an extra wire so they standardised on the 6 (I think)