Improving Headlamp output / How I did it – A Technical Discussion
Previously, on the
V650 forum, I had recommended getting the 65W Osram H7 “Off-Road” bulb and fitting it.
The advantage to this over all the Night Breaker Range was that if was designed for high vibration environments, had a long burn lifetime and produced more lumens and had a long lifetime
It offered :
2100 lumen (brightness) and a
+500 hour life,
Compared to:
1780 lumen, 340 hours - for the Osram Night Breaker, with slight blue tint.
1700 lumen, 350 hours - for the Osram Silverstar (not Sylvania), also with slight blue tint.
1620 lumen, 200 hours - for Philips X-treme Power H7.
1500 lumen, +500 hours - for ever other Standard H7 55w bulb.
HOWEVER, they stopped production of these 65W bulbs a couple of years ago. if you do fine any for sale they are more than likely to Chinese inferior copies
SO WHAT TO DO NOW to fit something that is inexpensive and long lasting / +500 hour lifetime
The only way forward (as I see it) is now to fit some headlamp bypass wiring so that the full system voltage gets to the STD 55W bulbs
OR if fitting lamps of +80W rating, the additional current flow does not melt the poor thin OEM wiring / switches.
Upon investigation of my V650 Mk1 and my V1k Mk2, I found that the voltage drop over the wiring to the headlamps was in the order of:
~1.3V on the 2009 V650 Mk1
and
~1.5V on the 2015 V1k Mk2
The max volt drop you want to see is 0.5V , preferably below 0.25V
You will note above that the newer V1k Mk2 had a higher volt drop than the 6 year older V650 Mk1
I was puzzled by this until I inspected the wiring size / counted the strands of copper in the headlamp wiring Cct on each bike.
The older V650 headlamp wiring had 20% more copper strands than the V1k.
THEREFORE, the resistance / meter run of wiring run would be greater on the V1k Mk2
Obviously Mr K had been on an economy drive on the later bikes 
Anyway, the result was that I calculated that I was losing something in the order of 36% of light output on the V1k Mk2
To confirm this, I went and purchased an inexpensive light meter and measured the headlamps light output as a reference, before I fitted the headlamp bypass wiring Cct as shown below .
Before with the OEM wiring (calculated at 1.0 sq mm for the V1k) in Cct, the light output reading was 550
The V650 wiring was calculated @1.25 sq mmAfter the 2.5 sq mm bypass wiring installed, the light output reading increased to 750. An increase of +35%
Success - Now I can see properly on the dark Scottish back roads.
All this wiring mod cost me, was approx. £35 in material and a bit of time ~2 days
In addition, with this wiring in place, I will now be able to easily upgrade to the 80W Osram H7 62261SBP “Off-Road” bulb (that seems to have replaced the old 65W bulb) which can be got for ~£6.50 each at various online stores and as low as £5.80 each if you buy in bulk.
These bulbs, from the Osram data sheet have an output of:
1950 lumen (brightness) and a
+500 hour life
Note - they are sold for
OFF ROAD USE ONLY so it is up to you if you want to fit them
Compared to ~ £16 each, for the most recent 55W Osram Night Breaker Laser Extreme +150%, which you will more than likely go through 2 or 3 sets as they are very fragile / have a rated 200h life and only ~1750 lumens output at most.
Therefore, I consider that this wiring mod is very £ reasonable / beneficial, in comparison with the added benefit of less maintenance
Yes I expect others will chime in below / flame off and say they are very happy with his direct fit +150% 55W bulbs less reliable >200h life bulbs,
but as I do live further north in the land of darkness at this time of year, I am happy with what I have done
Hear endeth this year’s lesson / technical discussion
Richard
