Speedo Bulb on 6v Electrics

[Danbretta]

Hi All,
I need to replace a blown bulb on my Li150 Special, all on original 6v electrics. From what I can see on the old bulb it reads 12v 2.5v. Searching online I can't find a straight replacement. most dealers are selling 2.2v or 5v

Does it matter which one I go for, just thougth I would check in case I start blowing other bulbs or introducing any problems into my circuit.

Thanks in advance

Dan

[CHRIS in MARGATE]

That "V" should read "W" for watts.
2.2 W would be fine as would 5W. The bulb is important; it serves as a shunt to stop the others blowing.

[Danbretta]

Thanks, I found some 3w ones, I'll use these. I dont recall there being an earth coming from the holder. I understand its advisable to put one on?

[CHRIS in MARGATE]

If you can tin it and get a blob of solder on it, then definitely run an earth from it.

[Fast n Furious]

12v 2.2W Ba9s bulbs were originally specified for 6v systems for 2 reasons.
1 A 6v 2.2w bulb was actually too bright and could be very distracting when riding in the pitch black.
2 Because lambretta voltage regulators are electrically quite crap, the peak voltages will easily pop a tiny 6v bulb

With 12V systems I generally use a 24V 2.4W speedo bulb but it also depends on the make of speedo and how translucent the speedo dial face is.
These bulbs are available from specialised sources in a whole range of voltages and wattage eg. 6v, 6.3v, 7v, 8v, 10v, 12v, 14v, 18v, 24v, 28v, 30v. etc

[Danbretta]

Ah I see now, I wondered what a 12v bulb was doing on a 6v system.

Thanks for the info FnF.