? halogen bulb for Honda CB900C

Just discovered that I have no low beam, just high beam.
Never taken apart a light, but the Clymer says that I can replace the
bulb (quartz halogen) but it doesn't give any part # or other way of
IDing the bulb so I know what to buy.
If you know what I need and/or have any advice about this, sure could
use the help.
Thanks -bill
BTW bike is an '81

 

take the bulb to the auto parts store. it'll have something on it that they
can identify.

 

The only difference I ever heard of was that the "motorcycle"
grade bulbs are supposed to be more shock/vibration
resistant. My experience leads me to believe this is not
relevant. I have always (soon 20 years) used plain "car"
H4 bulbs and neither the bikes (SR500/TR1/XT600), nor
the riding (quite a lot of potholes and gravel) has been
kind to the bulbs. The number of failures has been negligible.

N.B. I am more inclined to think there is a marked quality
difference between top brand bulbs and cheap ones.

 

I can offer no first-hand knowledge re: any durability differences between
car and motorcycle bulbs. However, I seem to remember reading that Honda
uses bulbs that look almost exactly like a standard car halogen bulb,
but the tabs on the base are sized/spaced differently, just enough that
a standard auto bulb won't fit. I would take the original bulb with me
and compare very closely before buying an auto bulb for your CB900C.

I can tell you that my experience has been that running a halogen bulb
in a motorcycle headlamp on significantly less than the normal voltage
will make them very susceptible to premature burnout.

 

In that case it is not a H4 bulb. That would be lika a M6 bolt with
1/4" thread.

A good idea in any case.

Very true. At low voltage, gas pressure inside the bulb will be to
low because there is not enough heat. The gas is what prevents the
metal in the filament taking off and being deposited on the glass.
Keep the connections in the headlight circuit in good condition.

 

Where *I* did claim the bulb in question was an H4 bulb?

I definitely remember reading an article in Motorcycle Consumer
News about how to modify an automotive halogen bulb (type unknown)
to fit a Honda, I don't remember the exact model but it might have
been an ST1100.

This site has a lot of info about bike lighting, and has a link to
the ST1100 H4 bulb vs. auto H4 bulb issue (2nd link):

http://www.webbikeworld.com/lights/

http://www.sporttouringusa.com/

I clicked on 'product search', searched for 'H4' and got this item:

Item #507, "H4 Adapter rings (pair) for VFR and ST1100 - Use H4 bulbs
in your bike. $12 per pair."

Or just go here:

http://www.micapeak.com/bike/ST1300/Lights.html

"Headlight Adapter Shims to use 9003 bulbs, $12/pr. SportTuringUSA.com
part number 00507. Honda uses a proprietary 45/45 watt bulb which has
three tabs like a 9003, but at different positions. These bulbs are
used in the ST1100 / 1300, VFR750/800 and Goldwing 1500s. The bulb
shown above is a 9003 with the shim mounted, showing 5 tabs instead
of 3. You must trim off the bottom 2 tabs so that the bulb will fit
into the housing. Without the shim, the bulb angles up instead of
pointing straight ahead. If you lose a headlight bulb on the road you
must get a $$$ replacement at a Honda shop, or own some of these shims."

 

Are you sure it's the lower voltage?

ISTR truckers running halogen bulbs at 9v get illumination
similar to sealed beams while extending the service life
of the bulb. (Read in an industry rag while waiting for
tires to be mounted on my truck.)

 

H4 or 9003 bulb will work - don't touch the glass (oil from fingers will
cause a hot spot and the bulb will crack/burn.
Clean with alcohol (rubbing type not drinking) if required.
Dennis Kirk cross-references '80-92 CB900 as their p/n 22-309 same bulb as
my '89 Kaw EX500.
I use H4/9003 with no problem. Available at any automotive store.
PQ

 

Yes. My experience was on a '77 KZ650B1 with an aftermarket halogen headlamp,
it originally came with a standard sealed beam lamp. There was a significant
drop in voltage at the bulb due to old bullet connectors that were dirty and
had lost some of their spring tension. I burned out multiple bulbs in quick
succession until I decided to investigate why. After fixing the wiring and
getting the voltage drop into reasonable figures, I never had another bulb
burn out.

My guess is there is a bulb life vs. voltage transfer function that has a
large dip in the middle somewhere, which may even be nearby to a local
maximum, and the voltage my bike was supplying was right at that low point.

 

It's something like that. I used to work with quartz-halogen lamps in
the theatre industry, and occasionally ran across tables giving output
and life VS voltage for different lamps, and lowering the supply voltage
would decrease luminosity and life both. I'm sure that the general
function and graphs are available from GE or other manufacturers.

The explanation that was given to me at the time (and it might be
somewhat simplified, high-temperature chemistry isn't my field) was that
the Tungsten-Halogen cycle (which is the reaction cycle that re-deposits
tungsten vapor back to the filament instead of the glass) has an optimum
temperature, and running your lamps at lower voltage lowers the
temperature below optimum. You get increased vaporization of the
filament, which lowers luminosity further (by darkening the glass
envelope) and lowers lamp life (by removing filament material more
quickly).

Of course, these are 120V lamps, and we typically don't rattle them
around as much as a MC lamp, but the lamp technology is largely the same.

 

Thanks everyone for all the feedback and information. Learned a lot, too.

-bill

 

"Mark Olson" <> skrev i meddelandet

<snip>

You never did. But you caught on to the thread just as I had
commented on whether there is a difference between a
bike H4 bulb and a car H4 bulb.
Not quartz bulbs in general or bike vs. car bulbs in general.

So I guess I might turn the question around:
Where did *I* talk about a bulb that was not a H4 ?

OK ? Let's talk motorcycles now, shall we ?

 

In my first posting to the thread, I really wasn't addressing whether
'bike' H4 bulbs were any different from 'car' H4 bulbs. I was using
the discussion about halogen bulbs for bikes as a good jumping in
place to bring up a related point about the differences in the bases
of certain halogen bulbs used on some Hondas, and it seemed like a
pretty good place to do it.

I said:
--------------------------------------------------------------------

--------------------------------------------------------------------

Then you said:
--------------------------------------------------------------------
In that case it is not a H4 bulb. That would be lika a M6 bolt with
1/4" thread.
--------------------------------------------------------------------

You didn't, but your response indicated that you wanted to discuss H4
bulbs, I never mentioned that type specifically, and didn't really want
to get into whether bike H4s were different from car H4s. Instead,
I wanted to make sure that someone who owns one of the various Honda
models that uses a psuedo-H4 didn't make the mistake of buying
a generic H4 bulb and then find out that it didn't fit properly,
or *worse*, buy one, stick it in, and not notice that their beam
pattern was totally wrong because the base wasn't fitting flat into
the reflector.

Righto. Right now my current obsession is thinking about how I can
put a hydraulic clutch on my SV650S without breaking the bank. I'd
love to fit the bits from an DL1000/SV1000S, but I am afraid the
engine casting won't have the screw holes nicely tapped to bolt on
the slave cylinder. I wonder if any SV owners out there have ever
done a hydraulic clutch conversion successfully. I am aware of the
aftermarket Magura and Hebo kits that attach to the stock rotary
clutch actuator mechanism with a short cable or pushrod, but I would
like to avoid introducing any more friction than absolutely necessary.

Yes, I know that cable operated clutches work just fine and I don't
need to do it...