Charging Question

If it's broken or just needs tweaked

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mdirk
Posts: 4
Joined: Sun Jul 01, 2012 6:36 pm

Charging Question

Postby mdirk » Sun Jul 15, 2012 2:10 pm

Hello all,

I have an 81 cb650 with a charging problem of course. When I measure voltage at the battery I get at most 12.6-12.7 at 5000rpm. I've been dealing with this for a while and have read up on the problems associated with these bikes. The old rotor shorted to the case when hot, so I got a rebuild from Tim Parrot and a new r/r. Still the same voltage. I've tested the ac current and I get around 40 from the stator at 4000-5000rpm.

The resistance between the black and white wire going through the brushes is 14 ohms, just curious if that is ok (as I haven't seen any specs on that), the rebuild has good resistance at 4-5 ohms.

Also, on the black wire coming out of the regulator(in the same connector as the r/w and g). It goes up to the fuses and splits off a half dozen times, it has continuity to ground even with all the fuses unplugged. I've tracked it to the starter button and by wiggling the wire there the ground does go away. Could this be stealing my charge? Is there a way to bypass the button and start the bike to check?

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Volker_P
Posts: 5508
Joined: Mon Mar 06, 2006 1:53 am
Location: southern Germany

Re: Charging Question

Postby Volker_P » Sun Jul 15, 2012 2:24 pm

Welcome here! :D

Of course wiggling wires should not change resistance values so in fact you seem to have a problem. I would try to fix this before any further experiments with possible further damage. An also have a look into the headlight where much of the electric connectors are hidden. This may give an idea of the status of the bikes' electrics.

In principle you can activate the starter relay manually by tapping the yellow/red cable to +12V directly.

It is possible that this short also killed your RR. You may see if it works when you fixed the cable or try to do the RR load test described on page 16-8 of the manal liked below.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum


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