Scooterotica

My scoot has over the last couple of months and for no obvious reason started to blow headlamp bulbs with worrying regularity. I haven't changed anything which i believe might have influenced this issue however Ive got through so many bulbs recently that I'm starting to think it can't just be down to a few of dodgy bulbs. Anyone have any suggestions why this may be happening, I've gone through all the connections and earths etc and nothing seems to be obviously at fault.

Matt

matthew wrote:My scoot has over the last couple of months and for no obvious reason started to blow headlamp bulbs with worrying regularity. I haven't changed anything which i believe might have influenced this issue however Ive got through so many bulbs recently that I'm starting to think it can't just be down to a few of dodgy bulbs. Anyone have any suggestions why this may be happening, I've gone through all the connections and earths etc and nothing seems to be obviously at fault.

Matt

Hi Matt,
Give us a few more details to work with: is it a 12V conversion or a standard 6V system? Is it AC or DC? for starters

Brake light bulbs are quite prone to blowing on some standard systems

Cheers,

Nigel

Hi Nigel,

Thanks for the reply, sorry I missed out some important info, it's 12v AC, 120BGM stator, been the same set-up for years but only in the last few months has the issue arisen. Been blowing halogen and normal 12v headlamp bulbs, both highbeam and dip beam going in quick succession. I generally ride with my headlamp on at all times.

Matt

I would check the regulator is working correctly, a voltmeter would help, your stator will kick out anything from 8-9 volts at tickover to over 20V at full revs The regulator regulates it lol, test it before and after the regulator, set to AC. check any earths are good

Monty wrote:I would check the regulator is working correctly, a voltmeter would help, your stator will kick out anything from 8-9 volts at tickover to over 20V at full revs The regulator regulates it lol, test it before and after the regulator, set to AC. check any earths are good

^ What he said

sideout wrote:

Monty wrote:I would check the regulator is working correctly, a voltmeter would help, your stator will kick out anything from 8-9 volts at tickover to over 20V at full revs The regulator regulates it lol, test it before and after the regulator, set to AC. check any earths are good

^ What he said

Although, if it's only the headlamp blowing as stated, then the reg must be fine. If you're sure that all wiring connections are good then it may be a dodgy switch or the lamp itself isn't secure enough in the lamp holder (vibration or poor contact pressure).
If all lamps are blowing, then yes check the reg.

I don't think they blow i think they sometimes just vibrate to bits,i have had 3 h4 bulbs go on me in as many months,good ones at that, and with different reg boxes.

If it is vibration related, a dab or three of silcone spaced round the side of the metal cap to stabilise it might work. You can easily trim excess away once its gone off.

it is just the headlamp so probably not regulator related, I guess it could be just vibrating, I'll try the silicone trick and see if that makes any difference, I set off for Eurolambretta on Saturday, I'm carrying more bulbs than blackpool seafront!

Thanks for all the suggestions - Cheers!

Do you have the festoon bulb fitted in the speedo and is it working?

I once had the same problem and it ended up being the festoon bulb and it's wiring.

The festoon would short and the headlight would blow.
This was on 6V electrics.