Author Topic: K7 electric question  (Read 1155 times)

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Offline Stev-o

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K7 electric question
« on: October 30, 2010, 04:05:57 PM »
Finally got the project bike's engine unstuck and tried to crank it. Oil pressure & neutral light came on, but when start button was pressed all I got was a buzzing sound from the electrics area behind the left side cover. The PO did some creative wiring that obviously was a bad idea.
All you experts, please take a close look and let me know what you think. Thx.


'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline cookindaddy

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Re: K7 electric question
« Reply #1 on: October 30, 2010, 05:19:51 PM »
Probably you should look at the starter solenoid, since it is probably the thing doing the buzzing when you push the start button? It is the thing in the top center of the picture with the big red wire going to it. With the battery disconnected, remove each of its wires and make sure that they are clean and that good contact is being made. The rest of the creative wiring in the picture (the twist nuts) is probably wiring to the alternator and may be ok and not the cause of your starter motor not working. You will see if it charges once you can get it started.
George with a black 78 CB750K (in Lion's Head, Ontario, Canada)

Offline scottly

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Re: K7 electric question
« Reply #2 on: October 30, 2010, 06:07:20 PM »
Also check the battery connections, and make sure the battery is fully charged.
Don't fix it if it ain't broke!
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Offline Spanner 1

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Re: K7 electric question
« Reply #3 on: October 30, 2010, 06:10:21 PM »
What the heck is that 2nd. fat wire ( with red tape ring on it ) connected with the battery + ( Red ) wire on the solenoid  ???... Should be red under one nut and black (+) to the starter motor on the other one, only :o
Also where's the battery ground going to ??
« Last Edit: October 30, 2010, 06:12:43 PM by Spanner 1 »
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline scottly

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Re: K7 electric question
« Reply #4 on: October 30, 2010, 06:22:40 PM »
Good eye spanner! Is the wire with the red ring the starter wire, and the ground tied to the other post?
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Spanner 1

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Re: K7 electric question
« Reply #5 on: October 30, 2010, 06:28:21 PM »
I bet  $100 your right Scottly, 'cos there is no ground wire on the engine mount bolt where it should be  ;)
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Stev-o

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Re: K7 electric question
« Reply #6 on: October 30, 2010, 06:31:28 PM »
What the heck is that 2nd. fat wire ( with red tape ring on it )

That cable goes to a plug that goes to wire harness [and starter sw?]

Don't have time to deal w/it now, gotta get my costume on for a wild party tonight! [live band, 10 kegs, 200 partyers!!]

Thanks.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline GammaFlat

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Re: K7 electric question
« Reply #7 on: October 30, 2010, 10:57:22 PM »
I looks like your rectifier and regulator have been replaced with an aftermarket unit (or something from another bike).  The finned thing near the bottom is probably your replacement part.  There should be a shell connector with 5 connections (rectifier) and another 3 or 4 connections (regulator) all leading to the finned mystery piece.  It may make sense to get an original regulator and build your own rectifier.  PinHead also used a $13 Ford regulator and documented that in a thread that's easy to find.  If your charging stuff works, you may want to leave good enough alone but I prefer to understand what I've got especially if someone has mucked with it. 

I'd also strongly consider replacing the fuse holder with a bladed arrangement. 

K6
K7 
Suzuki GN400 - Ignition fixed!
03 KLR650 - Doesn't do anything very well but.. well.. does everything.