Honda CX 500 Forum banner
1 - 20 of 29 Posts

·
Registered
Joined
·
1,163 Posts
Discussion Starter · #1 ·
While trying to track down a bad ground causing my headlight to dim slightly whenever a turn-signal is on, or when I hit the brakes, I found only one cable going from the negative side of the battery to a bolt, where the cable goes in betweenst the frame and the engine block. Not knowing there was a nut behind this aforementioned bolt .(until I heard a little "tick" when it fell and hit somewheres in there.....likes ta never found it either...lol)



But, anyways, after hanging that nut from my trusty little magnet, and holding it there with my finger until I could get that bolt started through it, I turned on the key and had the same result. So, I've got good ground there.



My question is, where are/ is the other grounds at that ground the light/s to the frame? Seeings how they are not grounded directly to the battery?



I even took the flasher unit off and applied die-electric grease to 'em....Nyet!
 

·
Registered
Joined
·
546 Posts
While trying to track down a bad ground causing my headlight to dim slightly whenever a turn-signal is on, or when I hit the brakes, I found only one cable going from the negative side of the battery to a bolt, where the cable goes in betweenst the frame and the engine block. Not knowing there was a nut behind this aforementioned bolt .(until I heard a little "tick" when it fell and hit somewheres in there.....likes ta never found it either...lol)



But, anyways, after hanging that nut from my trusty little magnet, and holding it there with my finger until I could get that bolt started through it, I turned on the key and had the same result. So, I've got good ground there.



My question is, where are/ is the other grounds at that ground the light/s to the frame? Seeings how they are not grounded directly to the battery?



I even took the flasher unit off and applied die-electric grease to 'em....Nyet!


Bearman, GL's have a main ground under the seat. Your fairing set up probably has a different ground for the front lights, on the Hondaline fairings, The 81's grounded through the bracket, Some 81's and all later had a separate ground wire outside the harness. Can't say for the Vetter.
 

·
Registered
Joined
·
4,104 Posts
Bearman

Most of the green wires you see around the headlight are commoned up in the harness

( as well as a few black wires BTW)

On the ZAB's and probably most CDI bikes, its around the air intake area where the harness is thinner

and from there one green goes off to the rear lights and indicators and one cable goes to the ground terminal

at the CDI box.

Only ever had fragments of TI harnesses and never stripped a complete one of those

but I expect a similar method is used.

If you suspect any grounding, theres no harm in laying in a fresh cable

connected to a good ground point to back up the old ones.

using the same colours would be advised to prevent any confusion
 

·
Registered
Joined
·
1,163 Posts
Discussion Starter · #4 ·
Well? After finding that green wire under the seat, and having taken it off, seeing the eye and the frame around where the eye seated was nice and shiney, I was kinda thinking that this is not where it was losing ground. But, goobered her with some die-electric grease nonetheless and slapped it back together.



.....And then tuned the key on...............NYET!........GRRRRRRR!!!





Well?.....Am reckoning that the culprit lay somewheres amidst that spaghetti jungle of a mess tie-wrapped to my front forks. No bucket for them wires which may grant a little easier access then it would were there a bucket to stuff 'em in. But, the fairing must come off now....Which reminds me of the gynocologist turned mechanic who got awarded extra points on his final exam, because the instructor had never seen a motor rebuilt through the exhaust pipe before........However, I digress.....



But, that now must wait til after dinner, as Papa got paid for a head-gasket job we did yesterday on his neighbor's lawn-mower.
 

·
Premium Member
Joined
·
2,510 Posts
What is your bike's year and model? This would be good information to include in your signature.



From your avatar, I assume it's a GL500. The main grounding point for GL500's is in front of the ignition coils. See this writeup.
 

·
Premium Member
Joined
·
2,510 Posts
Agreed, good observation.



If it's not the ground connection in front of the ignition coils then it would make sense to break out the voltmeter. A voltmeter can be used to quickly isolate the problem.
 

·
Registered
Joined
·
1,163 Posts
Discussion Starter · #8 ·
Although the main grounding wire for the wiring harness looked a bit corroded, and I did clean the terminal eye and around the bolt hole, I turned the key on?....

....NYET!! So, I took out all 4 of the bulbs, thinking perhaps 1 of them coulda been causing this mis-hap, and replaced them all with brand new ones?.......Again?...Nyet!!



So, I took off the trunk and checked the wiring going back to the tail lights. I didn't find any seperate ground for these wires and they looked and felt rather secure in the sockets.



Could the flasher unit itself cause this?
 

·
Registered
Joined
·
227 Posts
Does the dimming happen when the engine is at high RPMs (over 4000) or more at idle speeds like when stopped at a traffic light?



I'm wondering if 'perhaps' this is just an example of 'normal' operation of the bike? Could even indicate a slightly worn down battery?



I only ask because I wired in a cheapie volt meter using a fairing power source and I can watch the voltage drop with the turn signal operating or the brake light on when I am waiting for the green light at an intersection. I do not notice it - or at least not as much - using the turn signal at expressway speeds.



Just a thunk on a Friday nite.
 

·
Registered
Joined
·
2,601 Posts
It could just as easily be corrosion in a connector that gets the poower up there.



Clean all the connectors with contact cleaner and coat them with silicone grease before reasembly to keep th water and moisture out. Also, from some oddball experiences with cars, I like to turn everything on and measure to see if various ground points (engine block, front fork area etc) remain at 0V compared to the actual negative post of the battery. Do this with both th engine running and with it not.



Extra ground wires never hurt anything, especially if you can keep them somewhat hidden.
 

·
Registered
Joined
·
8,423 Posts
I recently had to make one of ,"Reg's" 7v regulators(Dead Easy) for one of my CX,



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=257



Even when fitted I noticed the grounding to the head light was not good with meter tests.Plugged a connector with a bit of wire on it and a round/fork M6 electrical connector on the other end and discreetly bolted it to a proper frame/ground point.

The grounding through the harness from the front is not as good as it should be IMHO.





HTH
 

·
Registered
Joined
·
1,163 Posts
Discussion Starter · #12 ·
Ya know? Now that ya mentioned it, the lights do get dimmer sitting there ideling, and brighten back up with the rpm's. It is the 2nd (or 3rd) year for this battery. It may well be time for another one, but not sure what kind of life expectancy is normal for these bikes.



Nontheless, I am going to Milwaukee (though a bit late) to that Rockerbox rally.



I did put the battery charger on it last night, set on low, for like 10 minutes, whilst I went to the parts store for light bulbs.



I shall pursue these other insights when I get back from Milwaukee. Probably tomorrow.



Thanks guys.
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
17,728 Posts
Bike batteries should last at least 5-6 years if they are properly looked after during the off season.

http://www.aegeansoft.com/silverwing/phorum/read.php?29,7836



If the headlight only dims with the signals/brakes at idle don't worry about it. The alternator doesn't have enough output at idle to keep the battery charged while running that much load so the difference has to come from the battery but it will charge up again when you bring the RPM back above 2500 or so. If it dims when the RPM has been over 2500 for a couple of minutes you may have an alternator or battery problem.
 

·
Registered
Joined
·
1,163 Posts
Discussion Starter · #14 ·
After running the bike all day yesterday, I thought perhaps that might lessen the dimming effect. But it didn't seem to. I'll take a volt-meter out and check the charging system in a little bit here, and post the results. I certainly HOPE it's not the dreaded "stator" issue, common on the cx's.
 

·
Registered
Joined
·
4,104 Posts
I have an LED voltmeter on mine and when I apply brakes or indicators I see the

overall voltage drop a bit

As said, its quite normal and to be expected.

Normally, the battery acts as a capacitor and helps smooth out these dips

Significant dimming of headlights may indicate the batterys not charging properly

because of battery, stator, connections or RR problems

or

Its possible The current to the headlight is being limited by poor connections,

switches or grounding.

Only some systematic testing would show what the cause is, but

often a damn good examination and clean up sorts things out.



For what its worth.

I had a recurring lazy starting problem on mine which I eventually traced

to my 'new' 18 month old battery.

The 'old' battery which I had given to my lad for his CX has transformed the

way it starts.



If I hadnt assumed "It cant be my 'new' battery", I would have got to the root of

the problem a lot earlier.
 

·
Registered
Joined
·
1,163 Posts
Discussion Starter · #16 ·
After checking all the grounds in the wiring harness and finding them in alright shape, I think I'll try hooking up a jumper cable from my car, or putting the battery charger on a medium charge and seeing if it may be a weak hot connection, as it seems the ground isn't at fault. I figure if I get the same symptoms with a good hot hooked in with the battery, then it must BE a weak hot wire, which may necessitate the taking off the fairing and checking into the spaghetti jungle that lurketh around my triple tree...Lol



The headlights and instrument lights dim somewhat more at idle than at speed. Noticable, to be sure, but, I'm thinking that ANY dimming can't be a good thing.
 

·
Registered
Joined
·
4,104 Posts
Heres mine in action

You can see how the indicators have a pull down effect

on the overall voltage and a slight dimming effect at tickover

but its not excessive

[media]http://www.youtube.com/watch?v=5EuL3m9pSJ4[/media]
 
1 - 20 of 29 Posts
Top