Engine: 5-port LML Engine Install (FAQs)

The replacement 5-port engine from LML is a popular Scooterworks product for vintage Vespa restorations - and for good reason: it's usually a faster, smoother, and more reliable motor than the original! Below, you'll find some of the most common questions asked about the 5-port engine's installation.

Q1. HOW DO I HOOK UP THE WIRING?

This is the most common question when installing the LML engine into a vintage Vespa without battery or signals. The LML stator is a "single" output stator, which means that all of the power comes through one wire, runs through the regulator, to the switch, and is then distributed to the bulbs and horn from there. NOTE: most US-model vintage Vespa scooters before MY1974 used a three wire output. On these (-'74) models, the stator had three wires (either 2 yellow and 1 red, OR 1 yellow, 1 blue, and 1 green) to feed the lighting system. This style of wiring will not work with the single wire stator, since most did not have an inline regulator and the power from the stator will not be distributed correctly. In order to properly connect the electrical system, a wiring conversion kit (shown, below) is required

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Q2. WHY ARE THERE PARTS LEFT OVER?

LML engines are shipped with some electrical components: a silver box (regulator), a red box (CDI). If you purchased the wiring harness kit, you will only be using the blue CDI/coil unit and the components that came with the conversion kit. These other components (the silver and red boxes) will not be used.  

Q3. HOW DO I CONNECT THE VOLTAGE REGULATOR?

There are three posts on the voltage regulator supplied with the EIKHK harness (above). Two of the posts are closer together and one is "separate". That separated post is the ground, connect the black wire there. The two posts closer together are both "positive", connect the blue wire here (either one).  

Q4. WHERE DO I CONNECT THE GRAY COIL ON THE BACK OF THE ENGINE?

This is another component of the engine that will not be used for the install. The blue CDI/coil unit mentioned above contains everything you need. Remove the grey coil and set it aside (you never know when you'll need extra electrical parts!). TIP: when you take the coil off, unscrew the plug wire from it and use it on the new CDI/coil combo. Use the wiring diagram (below) as a reference.   These are just the most common questions regarding the LML 5-port engine install - there are many more that you may have, so don't hesitate to call us at 1-888-968-3772.