The short life of an H4

[97tiger885]

I am about to replace  the third H4 on my 97 M-carbed steamer since May of this year.  I was told these mcs eat bulbs, but this is  a bit much.  (I think I replaced 3 H4s total in the 14 years I ran my K75.)  Has anyone found a solution to this problem...a particular brand of H4 or a different bulb altogether?  Does anyone know what the cause is?  Is it a voltage spike?... slightly too much voltage over an extended period of time?...excessive heat?    Electricity I don't understand but I would like to fix this.

[armadillo76]

There isn't any other problem with your electrical system? I've had decent luck with PIAA super white. I think that is what they are. Even my 80/80 PIAA bulbs took awhile to burn out. The super white's if that is what I actually have are plenty bright but draw no more than a regular 55W bulb. Maybe it is just a quality control issue?
Dunno, AndyB, NH, 96 Tiger/Sprint.

[Mustang]

I am about to replace  the third H4 on my 97 M-carbed steamer since May of this year.  I was told these mcs eat bulbs, but this is  a bit much.  (I think I replaced 3 H4s total in the 14 years I ran my K75.)  Has anyone found a solution to this problem...a particular brand of H4 or a different bulb altogether?  Does anyone know what the cause is?  Is it a voltage spike?... slightly too much voltage over an extended period of time?...excessive heat?    Electricity I don't understand but I would like to fix this.

Jon
on my 95 the headlights stay on while cranking the starter the relays don't shut the lights off .this is how it was designed by Triumph .......but on the 98 the relays drop the headlights as soon as you hit the starter button again this is how triumph built it !

So I'm thinking that if your bike a 97 is the same as the 98 's the headlights should be going off when you crank the starter .......maybe they are getting a surge when the relays turn back on to energize the headlights , you could try replacing the relays to the headlights and see if that stops you from eating bulbs .

The other problem is you ride it too much ................ :D  :D  :D

[93TigerBill]

Hi Guys,
Had the same problem with my '93 - headlights stayed on with engine crank.
Replaced RHS switchblock with one from an early Sprint - I can now switch off the headlights - and turn them on after startup.
Helps a little with more voltage to the starter also.
Regards,
Bill
'93 Caspian Blue 110,000 km

[hobie]

I have a 98 and I replace 2 bulbs a year.  I haven't noticed whether or not the lights shut off while starting.  I'll check it out tomorrow.

[97tiger885]

I haven't noticed whether or not the lights shut off while starting.  I'll check it out tomorrow.[/quote

I checked mine, the '97.  The lights do not shut off while starting.   I was given one theory on this: excessive amps.  It was suggested :  1. Check the fuse box to see what amperage the light circuit was, 2. Isolate the light circuit and measure the amps, 3. If measured amperage is close to that of the fuse, place resistor to lower amps, 4.If measure amperage  is not close, ?.   If 3, then the issues  become what kind of resistor, the durability of such resistors, the mounting of this resistor given the heat it will generate, the cost and whether dealing with all this is worse than replacing a few bulbs.  Are resistors generally waterproof and shock resistant? I am clueless.

[Mustang]

Alrighty then , now I bet I know what is happening to your headlights , watch them when you crank the motor . I bet they dim and brighten to the pulse of the starter motor ! :shock: This probably awakens the Lucas gods and causes the bulbs filaments to have a shorter life . It's my theroy and I am sticking with it  
I think instead of messing with resistors I would simply add a toggle switch somewhere in the light circuit so you could just shut them off while cranking , then of course you would have to remember to them back on . Or one could install a relay to the starter switch that drops the headlights while the starter is engaged then when you let off the button the lights come back on automaticlly hmmmmmmmmmmmm just like the 98's do .

[97tiger885]

. I bet they dim and brighten to the pulse of the starter motor ! :shock: This probably awakens the Lucas gods and causes the bulbs filaments to have a shorter life .... I think instead of messing with resistors I would simply add a toggle switch somewhere in the light circuit so you could just shut them off while cranking , then of course you would have to remember to them back on . .

They do dim and brighten.  I like the toggle switch idea.   That is something I could probably do myself with a minimum of self-inflicted damage.  As for the Lucas gods, I do not fear them: I happen to like warm beer.

[Mustang]

They do dim and brighten.  I like the toggle switch idea.   That is something I could probably do myself with a minimum of self-inflicted damage. As for the Lucas gods, I do not fear them: I happen to like warm beer.

Seriously though use the toggle to turn the headlight relays on and off and let the relays carry the high current to the headlights

[skoron]

But, both '97 and '98 have the relay to isolate the headlights from the starting circuit.  If the lights are flickering, then the relay is shot.

Replacing the relay cures the problem.
Installing the toggle keeps the problem from occuring again.

Best to do both, yes?

Skoron