TOPIC:

this does have some good vibrations to it.
but regarding keys, nope only ever one key in ignition.
bike key is always alone.


so how we go about identifying faulty connections inside the switch, other than continuously turning off and on?

jim

Probably have to remove headlight to gain access to ignition switch wiring. Most bikes have a multi pin connector from the switch to the main harness.

You will a good multi-meter to check for internal wiring problems with this switch. While you have the headlight off/removed clean all electrical connections in there

MFolks wrote:

Probably have to remove headlight to gain access to ignition switch wiring. Most bikes have a multi pin connector from the switch to the main harness.

You will a good multi-meter to check for internal wiring problems with this switch. While you have the headlight off/removed clean all electrical connections in there

Mfolks,

Here's what I'm not following:

If the bike can sit for days/a week, etc without draining the battery at all, then doesn't that rule out a parasitic power loss with the key off?

If so, then wouldn't the next thing to check for be a parasitic power loss with the key on, and the bike not running?

With a fully charged battery, Jim got 12.9 volts with the key on, and it dropped to 10.6 volts while cranking. Is it that 10.6 volts while cranking that is making you think the ignition switch is bad?

Also, is it your suspicion that the switch being bad is what caused the two voltage regulators to fail? How do we test the regulators?

Thanks

Perhaps when moving the handlebars wires are rubbing making contact with other circuits/grounds. You may have to start unwrapping/removing the black tape on the harness to look at the condition of the wires.

Insulation may be breaking down and this power drain may be very intermittant.

damn was hoping you were not going to suggest that but anything is possible,

sean there is a series of resistance tests that are done on the regulators to determine good or bad and both failed.

ok well guess will be pulling switch out for easier access and might as well chase the whole harness to check for rub marks.

this going to be fun.

thanks will advise on findings.

Harness has been traced, all wires with the potential of shorting have been repaired.

i still am not making the connection between a possible transient short and the bike charging at 12.9v @ idle and 13.5v @ 4000 rpm, and the bike's having eaten 3 regulators.

Can someone please explain?

ok as sean said have found shorts in wiring, mostly under tank area. all repaired and wiring harness recovered. have found no sign of an internal switch short but am not ruling that out. would like to know if the voltages i posted earlier at the regulator seem to be in the normal range or not. if they are not then i will dig deeper into the harness, iow open the whole thing up. if they do seem normal then will put the new regulator in and see where we stand charge wise.
thanks for the assist and the advice.

can someone please help?

I know I'm a little late to the party, but I'll give it a shot anyway.

You said at one point that you fixed the battery drain problem, but I didn't see you mention what you did. How did you fix it?

You're getting 72-73 VAC and Clymer calls for 75? I'd say this is OK. Not great, but it's not your problem.

Is your regulator adjustable? The one on my 77 650 has adjustment specs. It should be in your Clymer manual. But I'm pretty sure the charging system changed for 78. Does your Clymer manual have a procedure for checking the regulator? My Clymer does.

Are there any specs for charging voltage @ idle & @ 4000 RPM? 12.9 VDC @ idle doesn't sound too bad to me. Keep in mind that these bikes (at least my 77) has a rather marginal charging system, even when it was new. It has a switch for the headlight, and was never intended to have the headlight operate 100% of the time. Mandatory headlights was not the law in 77. With the headlight on @ idle, the battery is being discharged. Of course, if you get the engine up to 3000-4000 RPM, it should be charging again.

Is it still eating regulators?

first off cute pic,
second never did verify actual drain at that time.
this last round did not verify drain but did find 3 damaged wires with 2 showing burn marks under tank.
yes was getting 72-73 volts ac. replaced rotor now 75-76 vac.
no regulators are not adujustable on the 78 or the 79 i have, also have an 81 not sure on it though.
spec for vdc @4k is 14.5ish i believe. dont have the book with me atm. so cant verify now. there is no off switch for the headlamp on this bike. keep in mind that this bike is modified with wg power coil mod. dont think i makes a diff. at least it made no diff on the charging system before. i had disconncted it to make sure and had no change in the charging, but made one hell of a difference with runability with it disconnected. runs terrible without it.
dont know about continued eating of regulators. the one that was on it failed, 5 wire if i recall. put a 4 wire on and it worked for a bit then failed, but it came off the other bike i have, not the 81.
sean has a new one to put on but wanted to make sure of the voltages going to the regulator were correct before we installed it.
dont really want to burn up a $130 part if we can avoid it.
supposed to have someone coming to look at it tomorrow that is more experienced than i am on these small engine setups.
my experience is cars and larger.
would appreciate any advice that you can lend though.
anxious to get him rolling again. (and off my back, jab sean )
thanks jim

I am also using the WG coil power mod, and as far as I can tell, it doesn't affect the charging system. It also helps the running, but not to the extent you describe. Which makes me think that your electrical system as a whole may need some help. 3 damaged wires and burn marks is a good indicator. On my 77 650 I want to replace all the bullet connectors with new. I've hit all of them with a dremel wire wheel, then applied dielectric grease, and I still have a problem here & there. My front left turn signal doesn't work due to a bad connection, even after I repeated the above process. If you're really at your wit's end, I'd suggest replacing the electrical connectors. I know it's a pain, but I think that's the source of your problems.

I thought of one more thing you might try first. To date, the best upgrade I've done to mine is replacing the fuse box with a blade type box. I had been blowing fuses up to that point, and couldn't really determine why. With the new fuse box, the lights are brighter, the blinkers flash faster, etc, and I haven't blown a fuse since. It was the best $10 I've spent on my KZ.