Author Topic: Ignition switch... Tests good...still bad? Updated (Read 2183 times)

mick750F · « **on:** August 03, 2007, 11:24:38 AM »

I mentioned in another thread that my bike lost all power the other day while I was riding...'78 750F. All of a sudden it just shut down. Fortunately I was just down the street from my shop. I was able to jiggle the connector on the bottom of the ignition switch and get it running long enough to get it back to the shop. When I removed the switch and tested it I was surprised to see that it had proper continuity in the different switch positions. So, can anyone tell me if a switch can test okay and still be bad? Where else should I be looking if it's not the switch?

Fuses are all good, back of fuse box is good, battery is new and charged. The bike has been running fine.

Mike

Rushoid · « **Reply #1 on:** August 03, 2007, 12:02:20 PM »

Mick, my switch ('78 750F) would test and work fine sometimes and not others. I've heard that it was a common problem on our bikes due to the routing of the cables (my clutch cable rubs on it). I replaced my switch, and the wire connectors going into it and haven't had a problem in the year and a half since. They don't cost much, so it might be worth it to replace it anyway. Just my opinion of course. Good luck!

TwoTired · « **Reply #2 on:** August 03, 2007, 01:39:27 PM »

It's not uncommon for electrical parts to become intermittent before they fail allogether.

There may also be some arcing/charing inside when current is forced through the contacts. The test apparatus may not place the same conditions on the device under test.

cheers,

cb350f_rider_73 · « **Reply #3 on:** August 03, 2007, 06:46:14 PM »

Another thing to check is your ground cable. If you get any corrosion on either end (or inside the insulation; I've seen it), you can wind up with intermittent loss of power despite reading good voltage on the battery itself.

doobiebro · « **Reply #4 on:** August 03, 2007, 06:52:52 PM »

I have heard of many ignition switch problems with the models around 77 and 78. Mine on my 78K was like that. I replaced it and no more problems. You could replace just the bottom, but for the few extra bucks you may as well buy the whole switch.

mick750F · « **Reply #5 on:** August 03, 2007, 07:07:57 PM »

Thanks for the input guys. I've ordered a new switch. Looks like no riding until Thursday.

Mike

crazypj · « **Reply #6 on:** August 04, 2007, 07:31:35 AM »

I soldered the red wire back onto mine and it still works after 20+yrs.
The clutch cable stressed wiring and solder joint failed (in a downpour, naturally enough

)
PJ

jdigga · « **Reply #7 on:** August 04, 2007, 11:07:08 AM »

My 78 also had a bad ignition switch, so I swapped the one from my 79 in. Also, with regards to the ground cable, for some reason the ring on mine where it attaches to the engine mount bolt was painted

so I can't imagine there was very good contact there.

mick750F · « **Reply #8 on:** August 12, 2007, 05:37:56 AM »

It turns out that the ignition switch isn't bad. I bought an Emgo switch from DK. Partsnmore are out of stock. As I was plugging the new switch into the harness it fell apart in my hand. WTF!?!? What a piece of crap! The bottom section in one hand...the top in the other. I'd heard that these aren't a great product but this is ridiculous. I reassembled it to test it figuring I'd epoxy the POS back together once I knew it worked. Turn the key...nothing, nada, zip. I check the fuses...still good. I push a probe tester into the connector block to test for power...it's there. Now I'm thinking this new switch is bad. I'm getting really frustrated, my shop is about 88º, the humidity is pretty much at steam bath levels and I just want to ride. Out of desperation I decide to connect the old switch. At least with that one I seemed to get power if I jiggled it around...the new one wasn't doing that. Old switch in...nothing. If tips off it's perch...I have power. Huh? Move it around...power on, power off...etc. Hah! I've got it! Showing no power I ran the tip of the probe through the wire bringing power to the switch about an inch back from the connector. Bingo! Wire is bad inside it's casing.

Now my new problem? I want to pull the wire out of the connector block, splice in a short length, put the connector back on and reinstall it back into the block. Well that wire with connector doesn't want to come out of the block. I know that just pulling won't do it and I've tried pulling while prying from the other side. It's not budging. How are they in there and how do they come out? Anybody?

Mike

frostypuck · « **Reply #9 on:** August 12, 2007, 07:49:31 AM »

Mike,
To get the connector out of the block, there a little dingle-thingy inside the block that is shaped like a spear point. You have to lift that up from the backside and pull the offending wire out at the same time. I have a tiny little screwdriver to do the trick, but essentially, you slide the screwdriver in on top of the connector from the same side the wire comes out, and you'll feel the clip.
Now after all that typing, I seem to recall that the tang is on the metal connector, and you push it down from the opposite (goes-into) side. Load of help I was, huh?

Later,
Chris

mikedialect · « **Reply #10 on:** August 12, 2007, 11:09:00 AM »

Quote from: mick750F on August 12, 2007, 05:37:56 AM

It turns out that the ignition switch isn't bad. I bought an Emgo switch from DK. Partsnmore are out of stock. As I was plugging the new switch into the harness it fell apart in my hand. WTF!?!? What a piece of crap! The bottom section in one hand...the top in the other. I'd heard that these aren't a great product but this is ridiculous. I reassembled it to test it figuring I'd epoxy the POS back together once I knew it worked. Turn the key...nothing, nada, zip. I check the fuses...still good. I push a probe tester into the connector block to test for power...it's there. Now I'm thinking this new switch is bad. I'm getting really frustrated, my shop is about 88º, the humidity is pretty much at steam bath levels and I just want to ride. Out of desperation I decide to connect the old switch. At least with that one I seemed to get power if I jiggled it around...the new one wasn't doing that. Old switch in...nothing. If tips off it's perch...I have power. Huh? Move it around...power on, power off...etc. Hah! I've got it! Showing no power I ran the tip of the probe through the wire bringing power to the switch about an inch back from the connector. Bingo! Wire is bad inside it's casing.

Now my new problem? I want to pull the wire out of the connector block, splice in a short length, put the connector back on and reinstall it back into the block. Well that wire with connector doesn't want to come out of the block. I know that just pulling won't do it and I've tried pulling while prying from the other side. It's not budging. How are they in there and how do they come out? Anybody?

Mike

Sounds like we're having an identical problem

IndianRider · « **Reply #11 on:** August 14, 2007, 07:38:40 AM »

i got the same problem sometimes on my 1978 K8 .. in a dark garage, i can actually see the spark through the connector when i jiggle the connection with my hand ..

ChippK8 · « **Reply #12 on:** May 13, 2008, 11:09:52 PM »

Hmm, I am having a problem that sounds identical to this (78 750k).

Last week, I started up my bike and it died (lost all power) after about a minute of idling. I hooked up my battery charger on boost for a second and it came on and no problems after that. Then a couple nights ago, I rode about 10 miles to my Mom's house. On the way back I pulled off the highway to get something from the store and it died right after I took the left turn. I was right by a parking lot so I pushed it in. I jiggled the battery cables some and I got power again. I rode over to the store and when I came out it started fine, but after my first turn it died again. This time I had to get my truck and load the bike up.

I got a new battery, getting 12v out of that. I have 12v on the Red wire going into the ignition switch and I have tried jumping the wires in the connector, but I still cannot get power. After reading this thread I am starting to suspect the connector itself, I figure if the switch was bad I would be able to jump it and get electricity.

And I do get continuity through the ignition switch in both the RUN and PARK positions.

neil10 · « **Reply #13 on:** May 14, 2008, 04:29:09 AM »

Inside switches through use a groove is formed which limits contact
when desperate for ride trace wies back to connection
4 wires join two together mine were the diagonal and away you go

crazypj · « **Reply #14 on:** May 14, 2008, 06:16:31 AM »

Quote from: frostypuck on August 12, 2007, 07:49:31 AM

Mike,
To get the connector out of the block, there a little dingle-thingy inside the block that is shaped like a spear point. You have to lift that up from the backside and pull the offending wire out at the same time. I have a tiny little screwdriver to do the trick, but essentially, you slide the screwdriver in on top of the connector from the same side the wire comes out, and you'll feel the clip.
Now after all that typing, I seem to recall that the tang is on the metal connector, and you push it down from the opposite (goes-into) side. Load of help I was, huh?

Later,
Chris

There is a special tool made for removing these connectors but its easy enough to make your own from a piece of flat strip. The steel banding on packages is about the right thickness but way too wide.
It can easily be cut down to about 2.5mm wide and the edges de-burred on an oil stone (sharpening stone)
Coke can or similar is too soft to be any use, it needs to be steel.
Small screwdriver will work, but they tend to open up he plastic block too much so blade can fall out
PJ

jdigga · « **Reply #15 on:** May 14, 2008, 07:02:50 AM »

Quote from: crazypj on May 14, 2008, 06:16:31 AM

There is a special tool made for removing these connectors

I found a small paper clip works too.

mick750F · « **Reply #16 on:** May 14, 2008, 05:23:07 PM »

Quote from: ChippK8 on May 13, 2008, 11:09:52 PM

Hmm, I am having a problem that sounds identical to this (78 750k).

Last week, I started up my bike and it died (lost all power) after about a minute of idling. I hooked up my battery charger on boost for a second and it came on and no problems after that. Then a couple nights ago, I rode about 10 miles to my Mom's house. On the way back I pulled off the highway to get something from the store and it died right after I took the left turn. I was right by a parking lot so I pushed it in. I jiggled the battery cables some and I got power again. I rode over to the store and when I came out it started fine, but after my first turn it died again. This time I had to get my truck and load the bike up.

I got a new battery, getting 12v out of that. I have 12v on the Red wire going into the ignition switch and I have tried jumping the wires in the connector, but I still cannot get power. After reading this thread I am starting to suspect the connector itself, I figure if the switch was bad I would be able to jump it and get electricity.

And I do get continuity through the ignition switch in both the RUN and PARK positions.

I might have reported it in another post last year but it turned out that I had 2 problems at the same which just about had me pulling my hair out before I solved it. I ended up replacing a section of the wire bringing power to the switch as mentioned above but when it was all done the problem remained. ARRGGHHH!!! Time to start tracing wires. It turned out that I also had a loose ground at the condenser along with the bad switch...yes, the switch was bad. Tighten ground...and use some Lock-Tite...replace the switch with one from frostypuck and there have been no problems since.

Mike

ChippK8 · « **Reply #17 on:** May 14, 2008, 08:23:56 PM »

One thing I noticed today is that at some point one of the bolts that attaches the headlight to the fork had fallen out. Since that is where it grounds I am going to bet that that is what caused the problem, but replacing the bolt did nothing.

ChippK8 · « **Reply #18 on:** May 19, 2008, 02:43:21 AM »

Well, I was able to figure out my problem. Turns out that the connectors that connects the fuse box to the wiring harness was fried. I had already converted it to use cartridge fuses a couple months ago, but I went ahead and put new wires and connectors and removed the previously obsolete and now fried connector. Then I covered the crimp connectors with some heat shrink to provide some weather and shorting protection.

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Author Topic: Ignition switch... Tests good...still bad? Updated (Read 2183 times)

jdigga

jdigga