Modern Vespa

Hi guys - need a bit of help with a headlamp issue before I take my scoot in for her first MOT on Saturday. Got a sneaky suspicious feeling she's going to fail on the beam pattern...

I recently upgraded from incandescent (?Bosch type) to H4 halogen bulb. Dipped beam is fine; full (high) beam looks brighter as it should, but the beam doesn't seem to throw any further ahead.

Basically I have swapped one like this: http://www.autobulbsdirect.co.uk/RMU395-RING-12v-35-35w-PX15D-Headlamp-Bulb.html

...for one like this: http://www.autobulbsdirect.co.uk/RMU417-RING-12v-35-35w-BA20D-Halogen-Headlamp-Upgrades-395-Std-Bulb.html

From memory (without popping the bulb out to check), the lugs on this bulb prevent incorrect installation.

Did I see a thread on here which said this upgrade needs a bit of wire swapping?

Much appreciated as always...

Best,

Mark

That was me that said that, but a Ring 35/35 Ba20d should be absolutely fine! If you're worried put the globe back in for the MOT. I'd be surprised if they noticed tbh.

I am afraid the two bulb types have different focus points and work differently with the reflector. The cap on the halogen shows that and your different light pattern proves it. I am not sure if rewiring will help here.

Light bulbs are one element of a precise optical equation, in cooperation with the reflector, and changing one element messes up the result. Best example are the HID bulbs inserted in a halogen-based reflector. If I were you, I would bite the bullet and go back to the correct bulb type. You want better light on the road, don't you?

Hi , if the dipped beam pattern is ok then it will pass MOT testing as only your dipped beam is part of the test, as long as the main beam works it is ok for MOT

1+ Hence the reason (per my prior posts)...I'm still in the middle of installing a Xenon Projector kit and replacing my HID install. The Projector does not rely on the reflector bowl except for holding the Projector in place and you can (and will) still need to adjust the beam level. Post on DIY install to follow...it's not a simple "plug and play".

The performance of the stock headlight with the stupid bosch bulb would suggest there is an error somewhere in the equation.
I replaced mine with a 35/35 395H halogen out of a Lifan(chinese scoot), direct swap. Dipped is significantly brighter, on highbeam the pattern is terrible(like the stock bulb).