# Vintage Vespa Turn Signal Lights Project

#### low profile

Joined Dec 5, 2018
8
Hi

Using a Vintage Vespa.
Does not have any signal lights.
Would like to start a small project by modifying Ampulla Bicycle Light turn signals.
https://www.amazon.com/Ampulla-Rechargeable-Bike-Tail-Light/dp/B06XXHDQLN

I plan to de-solder 1 bike signal LED each side & connect it to a bigger & brighter LED.
(Would be adding 2x LED for Rear, 2x LED for Front).
I guess it wont work as the current driving the small LED is too small to drive the bigger LED.
So i would need either a relay or transistor to accomplish this.
Which one should i go for & why?

Ampulla uses 3.7V rechargable battery
My Vintage Vespa runs 6V AC fed directly from a 6 pole flywheel magneto (nominal 6V),
does not have any batteries,
so i plan to use a power bank to charge the Ampulla & drive the new brighter signal lights at the moment.
In future i plan to run the whole circuit from the Vespa flywheel magneto.

Thanks

#### shortbus

Joined Sep 30, 2009
8,429
My Vintage Vespa runs 6V AC fed directly from a 6 pole flywheel magneto (nominal 6V),
does not have any batteries,
Does it have a headlight and tail light now? Never saw a old Vespa without them.

#### Hymie

Joined Mar 30, 2018
963
I think the indicator unit you are considering would be OK for the rear of your Vespa, but you will need something different for the front turn signals. However, given that you will want a single switch action to operate both front and back vehicle indicators, I would suggest you investigate an alternate all-in-one solution.

To that end, I would give serious consideration to rectifying the 6Vac from the magneto and use this dc voltage to power whatever you plan to add on. The rectified magneto output will give you 7Vdc (taking into account the bridge diode drop). If your proposed solution operates at 12V, you could add a voltage boost module to achieve this. The cost of a bridge rectifier & voltage booster could be had for less than $10 (depending on the current draw), which is probably minimal in terms of the cost of an all-in-one front/rear turn signal unit. Thread Starter #### low profile Joined Dec 5, 2018 8 Does it have a headlight and tail light now? Never saw a old Vespa without them. It's a Vespa Super 150 1966 model. It does have a head light & tail light. Thread Starter #### low profile Joined Dec 5, 2018 8 I think the indicator unit you are considering would be OK for the rear of your Vespa, but you will need something different for the front turn signals. However, given that you will want a single switch action to operate both front and back vehicle indicators, I would suggest you investigate an alternate all-in-one solution. At Ampulla, there are 5 surface mount LEDS for each side. Was considering to de-solder one each side and wire it to the front & replacing it with a brighter bulp. To that end, I would give serious consideration to rectifying the 6Vac from the magneto and use this dc voltage to power whatever you plan to add on. The rectified magneto output will give you 7Vdc (taking into account the bridge diode drop). If your proposed solution operates at 12V, you could add a voltage boost module to achieve this. The cost of a bridge rectifier & voltage booster could be had for less than$10 (depending on the current draw), which is probably minimal in terms of the cost of an all-in-one front/rear turn signal unit.
I'm looking into "Full-wave Rectifier with Smoothing Capacitor" at https://www.electronics-tutorials.ws/diode/diode_6.html.
Any parameters of the diode that i should consider for automotive use, let me know. Tq

#### shortbus

Joined Sep 30, 2009
8,429
It's a Vespa Super 150 1966 model.
It does have a head light & tail light.
That is close to the year my friend had back in that time frame(I graduated high school in '66). Why not take power from the headlight circuit for your turn signals? A wire from the 'hot' side of the headlight switch to the center terminal of a double throw switch then from that to left and right turn signals. If you look there are switches made for motorcycles that fit the round handle bar that are used for turn signals This is just the first link I found for what I'm talking about - https://www.amazon.com/Kawell-motorcycle-universal-handlebar-conversion/dp/B008G4YMHY

#### Hymie

Joined Mar 30, 2018
963
In terms of the parts required to rectify the 6Vac and boost it to 12Vdc – to give you a large selection of possible turn signal solutions, almost any bridge rectifier with the appropriate current carrying capacity should suffice. You may need a smoothing capacitor across the bridge rectifier output. But the boost module below has an input voltage range of 3V to 35V so should be fairly tolerant to input voltage changes. The output voltage is adjustable from 4V to 40V (but as a boost module cannot be lower than the input). With a rating of 80W (load), it should be plenty enough to drive any LED lighting system you add to the scooter.

I would consider buying a suitable rectifier & boost module and connect it to the scooter 6Vac to see how it performs.

https://www.ebay.co.uk/itm/DC-DC-3V...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

#### low profile

Joined Dec 5, 2018
8
That is close to the year my friend had back in that time frame(I graduated high school in '66). Why not take power from the headlight circuit for your turn signals? A wire from the 'hot' side of the headlight switch to the center terminal of a double throw switch then from that to left and right turn signals. If you look there are switches made for motorcycles that fit the round handle bar that are used for turn signals This is just the first link I found for what I'm talking about - https://www.amazon.com/Kawell-motorcycle-universal-handlebar-conversion/dp/B008G4YMHY
Manage to find a turn signal switch made for later Vespa Model, will use this.

#### low profile

Joined Dec 5, 2018
8
In terms of the parts required to rectify the 6Vac and boost it to 12Vdc – to give you a large selection of possible turn signal solutions, almost any bridge rectifier with the appropriate current carrying capacity should suffice. You may need a smoothing capacitor across the bridge rectifier output. But the boost module below has an input voltage range of 3V to 35V so should be fairly tolerant to input voltage changes. The output voltage is adjustable from 4V to 40V (but as a boost module cannot be lower than the input). With a rating of 80W (load), it should be plenty enough to drive any LED lighting system you add to the scooter.

I would consider buying a suitable rectifier & boost module and connect it to the scooter 6Vac to see how it performs.

https://www.ebay.co.uk/itm/DC-DC-3V-35V-To-4V-40V-Step-Up-Power-Module-Boost-Converter-12v-24v-Converter-OS/232868644474?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649
Certainly more selection for 12V, will be going down this path. Tq

#### low profile

Joined Dec 5, 2018
8
Hi,

Purchased the bridge rectifier and boost module.
Mechanic is not confident on where from the flywheel magneto to tap and insist it won't be sufficient to power anything more than what few light bulbs.
He is suggesting to buy a bike 12V battery and run everything from it.

1_How do i test the maximum current i can draw from a flywheel magneto?
2_Where is the best place from the circuit attached to get the 6V AC supply for connecting to the bridge rectifier & smoothing capacitor?
3_If running from the battery, do i also need a circuit to recharge the battery?
(some say since the battery is not used for starting the bike hence not necessary)
4_Anything i should look out for when choosing a flasher relay? i'm looking at this at the moment:
https://www.ebay.com/itm/CF13-12V-3...h-Relay-For-Turn-Signal-Light-P-/113031010211

Thanks

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#### Hymie

Joined Mar 30, 2018
963
The total power of all bulbs exceeds 40W (driven by the magneto), therefore there should be sufficient headroom on the available power to drive indicator LEDs – there would be no need to add a battery to complicate things.

I would recommend you use a multimeter to locate the ac voltage on the Switch Board, and feed this (fused) to the ac input of the bridge rectifier. The flasher relay module looks OK, with a rating down to 20mA.

I have attached a circuit diagram showing the connections between the magneto ac, bridge rectifier and boost module.
Capacitor C1 at 1000 μF should provide sufficient smoothing for the LED current draw.

With no vehicle lights on, the available power at the output of the boost module (12V) should exceed 40W.

One thing to bear in mind is that one of the magneto outputs may be referenced (connected) to the vehicle chassis – and therefore to avoid short circuits over the bridge rectifier, the +/- outputs and boost module output should be floating (and not connected to the chassis).

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#### low profile

Joined Dec 5, 2018
8
Many thanks for the circuit & advice on danger of short circuit Hymie.
I'm looking at tapping Wire 13 (Yellow-Black) & Wire 3 (Black). Will be verifying with a multimeter first.
Wire 3 seems to be connected to chassis, guess I'll tap Wire 13 & chassis.
Anything i miss / potential issues, do advice. Thanks