Electrics help req...

[Ckennedy]

Evening all. A short while a go I made my own head light relay kit but since then I have used the head light a couple of times and it keeps blowing my headlight
So what I need help with is what amps are supposed to be sent to the headlight using the new wiring loom withthe relays. I currently have 30amp cable fitted and I am wondering if this is my problem. Am I over loading the headlight bulk with the ampage or is it more likely to be something else. I did have a 25amp fuse fitted so I am rather unsure.

Any help on what amp cable to use would be much appreciated and any other hints and tips you may have as I can not figure out what the problem is.

[Serlant]

a Bulb will only draw as much amperage as it can handle, its higher voltage than advertised that will kill bulbs, how is your reg/rec?

[Ckennedy]

The bike is charging fine. 14.5volts with lights on at tick over and 13.6ish volt when revving around 5000rpm. I was thinking that a spike in the voltage would do it but after seeing it was charging fine but still blowing my headlight I got a bit confused.

[VTRDark]

This may help http://www.vtr1000.org/phpBB3/viewtopic ... re#p294271

(:-})

[Ckennedy]

I do remember reading that post from last time and though my fuse may be to big that doesn't seem to solve my problem, or does it and I have miss read something? The obvious problem I would have thought would be to may volts but as the voltage is fine I went for amps being the issue but was under the impression that the bulb would only draw what it needed which has been confirmed further up the thread.

What would cause the bulb to blow but not the fuse? It doesn't blow straight away, the first time it was on for maybe 30-40 mins and the 2nd time 10mins at best. The wiring diagram in had was pretty straight forward to follow so I'm pretty sure it is all wired up right. It works fine with the standard wiring loom so it is something to do with the loom I have fitted, I just can't find what.

[macdee]

what size of relay are you using
are all connections good what about the lamp holder connections
where is the new loom connected to

[Ckennedy]

what size of relay are you using
are all connections good what about the lamp holder connections
where is the new loom connected to

To be honest I am not sure what size the relays are. I'll have to go and check.
All the connections are good and it runs down the left hand side of the bike along the frame and follows the clock wires around to the front. The ceramic bulb holder is all OK. Again connections all OK. I'll go check then size of the relays now ..............

All the relay says on it is 12v ++1323 there is a long part number on there too but its to cold to stand outside and try to read it

[Tweety]

what size of relay are you using
are all connections good what about the lamp holder connections
where is the new loom connected to

To be honest I am not sure what size the relays are. I'll have to go and check.
All the connections are good and it runs down the left hand side of the bike along the frame and follows the clock wires around to the front. The ceramic bulb holder is all OK. Again connections all OK. I'll go check then size of the relays now ..............

All the relay says on it is 12v ++1323 there is a long part number on there too but its to cold to stand outside and try to read it

Ok, you have a 25A fuse, and "30A" wiring... What does that mean in actual thickness of the wiring, since like I outlined in the post linked, going by what various people call "30A" wiring is a rather confused concept...

First of all, unless you have fitted half a dozen H4 bulbs, that should be a 7.5A or 10A fuse, nothing else, sticking a 25A fuse in there is about as safe as using a nail in the fuse box of the house like some morons do, to keep the fuses from blowing... That fuse will never, ever blow unless you directly short it, and hence the wiring will catch fire or melt long before it has any purpose of protecting you as the user... Ie, at 25A, you have no fuse, period... False feeling of safety...

You are absolutely correct that a bulb, like any other electrical item will only draw the current it needs... So, you either have an intermittent short somewhere, ie a connector or whatever that's unsealed and shorting to something like the frame... Or, your Reg/rec is on it's way out, and pumping out too much voltage... Start by measuring it, as you go through the entire rev range...

[Pete.L]

If all the connections are good it's either too many volts, poor quality bulbs or sticky fingers on the bulb glass.
Any dirt or grease left on them can cause hot spots which cause them to blow. Give another bulb a try after it's been cleaned with some methanol and only touch it with a clean cloth.

Pete.l

[Ckennedy]

It has to be a voltage problem. If it was a wiring fault it would blow straight away not after 10mins or so. Bulbs went in clean and dirt free each time. All connections are good. Just need to figure our why this extra voltage is getting through

[macdee]

It has to be a voltage problem. If it was a wiring fault it would blow straight away not after 10mins or so. Bulbs went in clean and dirt free each time. All connections are good. Just need to figure our why this extra voltage is getting through

if thats the case the new loom must have less resistance which has less voltage drop which in turn must be letting the higher voltage through to the lamp ( as tweety said your r/r must be producing a higher voltage in the first place )which R/R have you on the bike can you replace it with an other for quick test

[Tweety]

It has to be a voltage problem. If it was a wiring fault it would blow straight away not after 10mins or so. Bulbs went in clean and dirt free each time. All connections are good. Just need to figure our why this extra voltage is getting through

if thats the case the new loom must have less resistance which has less voltage drop which in turn must be letting the higher voltage through to the lamp ( as tweety said your r/r must be producing a higher voltage in the first place )which R/R have you on the bike can you replace it with an other for quick test

It's not an issue of "extra voltage getting through", it's a case of the extra voltage shouldn't be there in the first place, since it kills much more expensive things than bulbs...

12V bulbs usually survive up to 16-17V before blowing, which is a whole lot more than the ECU and CDI and gauge electronics can take on a extended time span... So, if you are 200% sure you have no possible short at any point, at all... Then you have a serious issue, that needs addressing, before it ends up costing you the price of a new bike in fowl smelling electronics... ECU's aren't cheap, not even used...

[Pete.L]

I tend to agree.
The only other senarios I can think of are to do with where you took your DC feed from and what route the cable take on the way to the headlamp.
I'm thinking
A) could your supply be floating(not regulated by the bridge retifier)
B) if the cabling was too close to your HT leads could you be inducing AC spikes into the lighting circuit and destroying the bulbs.

Engine running. Check for any voltage between the rectifier earth and the battery earth. There should be none. Then DC levels across the bulb and then from the battery negative and feed side of the bulb. Make sure you have the same rpm for both. About 3k should be enough.
You could try to see if you have any AC between the bulb and battery earth as well but I wouldn't expect any if everything is okay.
Report back and we'll se if we can make any sense of it.

Or just take your mod off and drive a little slower in the dark ya crazy bugger

Pete.l

[Tweety]

I tend to agree.
The only other senarios I can think of are to do with where you took your DC feed from and what route the cable take on the way to the headlamp.
I'm thinking
A) could your supply be floating(not regulated by the bridge retifier)
B) if the cabling was too close to your HT leads could you be inducing AC spikes into the lighting circuit and destroying the bulbs.

Engine running. Check for any voltage between the rectifier earth and the battery earth. There should be none. Then DC levels across the bulb and then from the battery negative and feed side of the bulb. Make sure you have the same rpm for both. About 3k should be enough.
You could try to see if you have any AC between the bulb and battery earth as well but I wouldn't expect any if everything is okay.
Report back and we'll se if we can make any sense of it.

Or just take your mod off and drive a little slower in the dark ya crazy bugger

Pete.l

Well, good creative thinking all of the above... Buuut... If he manages the feat of having the supply floating, or getting AC spikes in to it, by any means of creative wiring, it still boils down to a single cause in the end... Defective R/R... Plain and simple...

The R/R takes three AC wires in, and two wires out, one ground and one positive... There is no amount of creative wiring that can bypass the R/R, unless you hook something directly to that stator by those three wires, which I highly doubt he has done... As for floating, yeah, he "could" have a floating ground, but that would also mean that his bike wasn't charging, since he cannot manage to disconnect both the R/R ground from the battery ground, and the bulb ground from the both of them, not without the bike going entirely dark... And even if he did, that could never amount to a higher than normal voltage over the bulb anyways, only lower...

So, either the R/R is defective, with one of the three diode phases always conducting (at least partially), and spiking voltage above normal when it's overlayed on the other two phases... That happens, usually, but not always around 4k+ revs, on a stock Honda R/R, since that's the rev/voltage that corresponds to when the archaic regulator is starting to actually do any amount of work, and changing the dynamics slightly (ie heating the diodes)... Or he has an intermittent short somewhere... Ie works for a while and when you hit a bump in the road, *pop* goes the bulb... Should be the fuse, really, but since he effectively has no fuse, the bulb is the first thing to die...

A fully functioning R/R should never, ever allow anything above 15.4 V through, and should at all times except on low/rough idle with a cold engine, deliver between 13.2 and 14.8 V, and very rarely go outside that...

[Tweety]

BTW, a reasonable way to test it, if you haven't got a good multi meter, and a fair knowledge on how to use it, is by simply disconnecting the R/R and then revving the bike, or even riding it for a short while... If the battery is decent, you get a fair while before the battery is flat, and if the bulb still blows, you most definitely 100% sure have a intermittent short somewhere (except for the above, with greasy hands)...

If not, go back to the R/R... It's 99% sure to be it if there is no short... There really is no other component that can create higher voltage in the charging/electrical system, than the R/R, and the only way a bulb will blow like that, is grease/bad bulb, short and over voltage... There are no other ways...