Headlight bulb

[Lewes96]

Hi, dip beam has gone in my 3 1/2 Strada. 1977 bike. Not had it on the road for many years so getting used to what goes where so, does anyone know a good source of bulbs and the type needed? This is an unmodified bike so running standard electrics

[EVguru]

If this is an original CEV reflector unit and you want to keep it, then only use an Osram bulb. The position of the filament is critical to producing a proper beam pattern.

[George 350]

Hi,
The type of bulb you need for an original CEV headlight is a Bosch BA20D fitment, and standard is a 12V 35/35W rating. If everything is OK electrically, you can run a 12V 45/40W without issue.
Regarding the make of bulb as alluded to by Paul, the best thing is to use a well known brand, as filament location should be to a standard. I run a Cibie light unit and my experience with cheap low wattage H4 bulbs from China is that you don't get a beam on dip, but with the Osram Nightrider bulbs you do. Side by side comparisons don't show anything suspicious though. Odd.
You can get the bulb in Halfords, but no idea as to what the label number is. If you don't mind waiting for post, Paul Goff does some good deals, including quartz halogen upgraded ones.
See:http://www.norbsa02.freeuk.com/goffybulbs.htm for more details. I find him a nice chap to deal with.

Regards,
George.

[Lewes96]

Thanks for the replies - I will follow up

[penman]

Just to echo what George said, I would recommend Paul Goff. Knowledgeable and helpful and with a good stock of options.

By the way, it is worth keeping an eye on the developments in LED headlamp bulbs, which can give a lot more light for lower power. Keep well away from cheap ones, there is a lot of complete rubbish on the market, but the well-known makes (Philips, Osram, etc) are OK. Be aware that quality LED bulbs have a heat sink or a mini cooling fan on the back end of the bulb, so you need to check that you have sufficient clearance behind the reflector. My friend has fitted an H4 LED bulb on his A65 Lightning and it gives a good tight beam pattern and for just 30W, it's brighter than my 60W halogen bulb. A tight fit in the already crowded headlamp shell though!

[robint]

BA20D LED units are readily available on ebay and other sites but most of them are for snowmobiles ATV etc with single projector type headlights with dip being a dull main and are completely useless in reflector bowls. For a good beam pattern a point source of light is needed to utilise the reflector focus and the glass lens and get them to work in harmony.

Agree on Paul Goff as an excellent source but also look athttp://www.dynamoregulatorconversions.c ... s-shop.php as another option though I haven't tried the 'bulbs' yet.

[Lewes96]

Thanks for the tip re led; I will follow that one up too

[70sbikes]

I use a halogen 35/35 BA20D that I got on ebay from India. It works really well, and is notably brighter than standard.

[robint]

Halfords also sell them reasonably cheaply, unfortunately my bike eats the dipped beams fairly quickly for some reason (possibly a dodgy battery allowing voltage spikes??) so have been trying to find a replacement LED to hopefully reduce bulb replacement. When the spring comes and her moriniship comes off SORN slumber then I will go and play a bit more.

[penman]

Halfords also sell them reasonably cheaply, unfortunately my bike eats the dipped beams fairly quickly for some reason (possibly a dodgy battery allowing voltage spikes??) so have been trying to find a replacement LED to hopefully reduce bulb replacement. When the spring comes and her moriniship comes off SORN slumber then I will go and play a bit more.

It's more likely to be a faulty voltage regulator. Check the on-charge battery voltage, engine running at about 3000rpm. The upper limit is about 14.5v but 13.5 to 14v is a bit kinder to the bulbs. If it's regularly going above about 14.5v, not only will you get regular bulb failures, but the battery is likely to have a short life as well. It's also worth checking the wiring to the headlamp, intermittent earths, etc can also help to stress the bulb filaments, especially in a high vibration environment. It's a dog's life being a motorcycle bulb!

[Ming]

As far as headlights go - I've tried LED bulbs which were supposedly headlights with limited success. If you only want the light for visibility they are excellent, but if you want illumination they are poor. I have not tried the ones with cooling fans or heatsinks though (and I don't go out at night either, other than when I tested for the above comments!).