Headlight burned out -- One then the other

[sebjones906]

Is this common and why?

 

This has happened twice. The first itme it happened was about two years ago. A headlight burned out. Within two weeks the other side burned out.

 

Now..... Last week the Rightside low beam burnout, today the leftside died. (within 200 miles?????)

 

Is there somekind of electrical spike? Why one side and then the other.

 

The bike runs fine and everything functions correctly. Please don't suggest that the bulbs have similar life expectancy. I will not buy that one.

 

Has the same thing happened to others?

[1LIFE2LIVE]

+1; has happened to me twice in the last 34,000 miles.

 

In my experience they seem to last about 16/17k miles and the left bulb will burn out then the right side shortly thereafter.

 

After the last time I brought my bike into the dealer for a seal issue and had them check the headlights & they ended up replacing both electrical harnesses along with the seal under warranty - might be worth a trip to your dealer for testing.

 

I carry two headlight spares along with two bulbs for the turn signals in the small glove box.

 

08RT

[RichardSpag]

Used to happen very frequently on my RT. I tried a large number of expensive H7 bulbs and eventually gave up and bought a bulk pack of six cheap H7 bulbs of the internet to save money. That was about 30k miles ago and of course I haven't blow a bulb since! At 95K now.

 

Cheers

 

Richard

[dirtrider]

Morning Sam

 

H-7 bulb life is not the greatest. Just look at some of the auto threads on very short H-7 bulb life. And look in the archives here on Hexhead RT bulb life.

 

My Hexhead RT seems to go through H-7 bulbs pretty fast. Sometimes they go within days of each other and sometimes not.

 

I have monitored both the system voltage and bulb voltage on my current RT and nothing stood out as extreme, fluctuating, or abnormal.

 

Thinking maybe an occasional high or over-voltage issue I have even installed a high amp diode in each low beam power wire (that reduces the voltage by .7 volts to each bulb). They still blow at about the same rate.

 

As Richard noted the cheap bulbs seem to last longer than the specialty ones do.

 

Seeing as my H-7’s seem to blow on bike start up I’m thinking with the ZFE withholding headlights function until after engine start-up they are coming on line at full system voltage. SO my winter plan was to build a small electronic control to initially bring the low beams on in series (one bulb being the others resistor) so they initially come on line at about ½ voltage but I have been busy with other projects and haven’t gotten around to that little project yet.

 

A lot of automobiles run their headlights in series (about ½ voltage) for daylight running and that seems to have increased bulb life as well as lowering daylight parasitic current loads.

 

[racer7]

Dirtrider- you may know that the "slow start" concept is commonly used by flashlight hobbyists who build very high power halogen flashlights. Its purpose is precisely what you note- to reduce frequency of startup bulb failures.

 

The H-7 is pretty susceptible to startup failure and virtually all of mine that have failed do so on startup and typically one right after the other, as noted. The reason is that the H-7 has a small, tightly wound coil.

 

For the past year I've been running the Osram H-7 rally bulb (65W) that is an H-9 burner in an H-7 base. It has a longer, less tightly wound filament and so far no failures.

Too early to say for sure it is a big improvement but it is at least as good as stock bulbs. Also puts out 40% more light, a worthwhile gain.

[marcopolo]

I had two "expensive" bulbs blow simultaneously at startup a couple of years ago. I switched back to the inexpensive H-7s available at any auto supply store.

[BerndM]

I have 27,xxx miles on my 05 RT and am happy to report that that I have had to replace ZERO bulbs of ANY sort on the bike, including the 2 Motolights mounted to my lower forks.

Now that I've publicly stated that, I've probably screwed myself and will surely have to replace all of them shortly. That's just how it works, right?

I don't know if the fact that the bike has spent it's entire life here in SoCal, with our mostly warm / dry weather plays any part in this.

Regards

Bernd

 

 

[WestyLancs]

Likewise, R1200RT. When one bulb has blown, the other side has followed a few days

later. Four so far in 39,000 miles.

I'm currently using 'Tesla' bulbs marketed cheaply by Aldi / Lidl in the UK and find them to

last much better than the original fitment ones.

Touchwood, none blown for over 15,000 miles. (No doubt just cursed bulb life, like everyone else posting about longevity :-) )

[Twisties]

Choice of Headlight Bulbs

 

 

[EddyQ]

For the past year I've been running the Osram H-7 rally bulb (65W) that is an H-9 burner in an H-7 base. It has a longer, less tightly wound filament and so far no failures.

 

My first low beam went at 7.5Kmi. I replaced with a Osram H7 and it is going strong today with 18Kmi. Turns out the original bulb was a Osram H7. The left beam is still working fine.

 

This LINK has some info stating that life is proportional to V^-14. The example given says if a bulb is run 5% overvoltage, then the life is halved. So, the bulb life is very voltage dependant.

Also, if one bulb blows, then the wiring that was carrying current for both bulbs, instantly carries current for one. That will create an overvoltage on the other bulb for some fraction of a second. Also, as DR proposed, the ZFE likely turns on extremely fast. So, it too may create an fraction of a second overvoltage condition. Are these halogens sensitive to fractions of a second overvoltage? Donno. But I would guess yes.

 

It seems to me after reading, that the tungsten needs to heat and vaporize off the filiment in order to loose bulb life. So, as the transient voltage gets faster and faster, there comes a speed at which the filiment will not heat enough to vaporize with a given overvoltage. In other words, the duration of the overvoltage has to be for a significant amount of time in order for the filiment to overheat. So how long does the lamp take to turn on? Much less than a second, right? Perhaps 10 milliseconds (uneducated quess)? That tells me an overvoltage of much less than a second is significant. SO, when you monitor the voltage, you need something better than a handheld voltmeter to capture the damaging transient voltages.

 

Another electrical possibility might be due to the grounding. Often the 12V return wire is shared between all the bulbs and maybe other 12V things in the faring area. That results in the "ground" having some voltage on the wire relative to the battery minus terminal. Usually the more current on this return wire, the less voltage at the bulbs. But if the current at the faring drops, more voltage will occur at the bulbs. The wire shouldn't have much voltage if designed properly. But it doesn't take much voltage to lower halogen life. 0.6V (5% of 12V) halves a halogen life.

 

I donno what the answer is. It could be a combo of voltage being high nominally, voltage spikes (caused by fast switching and other fast changing events), ground issues and vibrations. I carry a cheap spare bulb and am glad the bulb is rather standard and can be bought at a autoparts store.

[Bullett]

Jan failed to mention that when the mileage on our RT's was close to the same we would have all four burn out within a few weeks of each other.

[CoarsegoldKid]

H7 bulbs suck electrons. Then they don't. Terrible bulbs. Our cars blow them too. All my vehicles with H7 bulbs are 2005 models. All have blown H7s numerous times.

I agree that the filaments are just not robust like an H4.

[Hall Vince]

The H-7 is pretty susceptible to startup failure and virtually all of mine that have failed do so on startup and typically one right after the other, as noted. The reason is that the H-7 has a small, tightly wound coil.

 

For the past year I've been running the Osram H-7 rally bulb (65W) that is an H-9 burner in an H-7 base. It has a longer, less tightly wound filament and so far no failures.

Too early to say for sure it is a big improvement but it is at least as good as stock bulbs. Also puts out 40% more light, a worthwhile gain.

 

Can I ask if you run these in your low beams with no problems?

 

I run them in my High beams (I have a pair of FF50's plumbed into my High beam and they are indeed very good.

I've not tried them in the dip as I was concerned about damaging something with the heat?

\v/

[Riverdawg]

Here's a link to Sylvania's spec on their H7s. From 90 hours for the cool blue, 510 for regular, and 930 for the LLs. Many of Sylvania's lamp come in the LL version and are only slighty more expensive.

 

 

http://sylvaniaautomotivecatalog.wbdev.com/ProductIdentifierD.aspx?mbid=4&MainBatchName=Headlight Lamps#

 

After you get to the site select the T-4 5/8 lamp specs

[EddyQ]

Thanks Robert.

 

So 50% of standard bulbs fail after only 510 hours with 14V. That is worse than I thought it would be. The failure curves (also available on the link) are consistant with the V^-14. SO, I ran a little simulation. Assume 4.5 ft of 14AWG wire from an to the alternator and that a bulb opens in 0.5uS, then the other bulb will get a transient that looks like below. The time of the transient is a bit faster than I originally guessed, but it does show some energy above the normal that may explain the failure of other bulbs. I wouldn't hold my hat on the failure rates I labeled since the speed at which the voltage is changing is likely very significant to the heat generated in the bulb.

 

 

BTW, a bad connection to either bulb will cause a simular transient. So, be sure the bulbs are installed to clean contacts!

[Turf man]

Count me in. I also tried PIAA H7 bulbs, do not waste your money. Take the advise that I found here, go to Wally Mart and pick up your new H7. Knock on wood this WM set has over 20000km on them.

[Lmar]

I replaced one on my RT with a regular H7 from Canadian Tire. When we had our 2000 BMW 3 series with standard bulbs I tried some of the high priced H7 bulbs. There was big difference in the brightness of the beam. The disadvantage was the bulbs burnt out in less than 6 months.

 

[racer7]

LMar, Hall Vince et al

 

The beauty of the Osram H-7 65W rally bulb is that it has the same life spec as a normal 55W H-7 bulb - because it is a stock 65W H-9 burner in an H-7 base. It is fundamentally different from all other high output H-7s because they all have the short tightly wound filament of the H-7. The Osram has an H-9 filament which is a bit longer and less tightly wound, thus can deliver higher output while maintaining normal life.

 

I use these bulbs in all spots on my RT so have 5 across the front (a hi, 2 lo, 2 Hella FF50).

 

I've been using them about a year with no failures. I used to use IPF 65W H-7 from Best Rest and would have killed 2 -4 of those in the same time period. IMO the Osrams are the best lo beam choice if you don't to use HID. There are no heat issues running 3, 65W bulbs in the stock RT housing- been doing it (first with IPFs, now Osrams) since I bought the bike in 2008.

[black99S]

yup

bulbs burn out

check the Silverstar claims for 30% better (new) brightness and you find the claim is vs a (used) bulb that has lost >20% in a year.

so carry a couple of spares and change them out every 2yr or 20,000km

[Hall Vince]

LMar, Hall Vince et al

 

The beauty of the Osram H-7 65W rally bulb is that it has the same life spec as a normal 55W H-7 bulb - because it is a stock 65W H-9 burner in an H-7 base. It is fundamentally different from all other high output H-7s because they all have the short tightly wound filament of the H-7. The Osram has an H-9 filament which is a bit longer and less tightly wound, thus can deliver higher output while maintaining normal life.

 

I use these bulbs in all spots on my RT so have 5 across the front (a hi, 2 lo, 2 Hella FF50).

 

I've been using them about a year with no failures. I used to use IPF 65W H-7 from Best Rest and would have killed 2 -4 of those in the same time period. IMO the Osrams are the best lo beam choice if you don't to use HID. There are no heat issues running 3, 65W bulbs in the stock RT housing- been doing it (first with IPFs, now Osrams) since I bought the bike in 2008.

 

This is most useful. I also run the 65w in a pair of FF50 and the main beam, will order up a pair for the low beams as well based on your experiance.

 

Oh and for some reason, my low beam bulbs have stopped blowing! The left hand one has been in nearly a year and what must be around 20,000 miles!!!.

I fitted a heavy duty in the RH one and it blew in 2000 miles, but it's replacement another HD bulb has lasted the winter. Dunno why!

\v/

[Dave_in_TX]

LMar, Hall Vince et al

 

The beauty of the Osram H-7 65W rally bulb is that it has the same life spec as a normal 55W H-7 bulb - because it is a stock 65W H-9 burner in an H-7 base. It is fundamentally different from all other high output H-7s because they all have the short tightly wound filament of the H-7. The Osram has an H-9 filament which is a bit longer and less tightly wound, thus can deliver higher output while maintaining normal life.

 

I use these bulbs in all spots on my RT so have 5 across the front (a hi, 2 lo, 2 Hella FF50).

 

I've been using them about a year with no failures. I used to use IPF 65W H-7 from Best Rest and would have killed 2 -4 of those in the same time period. IMO the Osrams are the best lo beam choice if you don't to use HID. There are no heat issues running 3, 65W bulbs in the stock RT housing- been doing it (first with IPFs, now Osrams) since I bought the bike in 2008.

 

This is most useful. I also run the 65w in a pair of FF50 and the main beam, will order up a pair for the low beams as well based on your experiance.

 

Oh and for some reason, my low beam bulbs have stopped blowing! The left hand one has been in nearly a year and what must be around 20,000 miles!!!.

I fitted a heavy duty in the RH one and it blew in 2000 miles, but it's replacement another HD bulb has lasted the winter. Dunno why!

\v/

 

I generally use Philips high output bulbs (Xtreme and +50) and still manage to get 18-20k out of them. I think there's some additional factor with the RT than just the rated life of the bulb used (long life, standard, etc.).