Registering an import Lui

Hi
I have just purchased an import 50cl Lui and have been rebuilding a 75cc Vega motor on the bench to fit to it - would it be better to get a dating certificate and register the bike as a 50 then change the engine details with DVLA after its registered, or fit the 75cc motor and then get a dating certificate and register it as a 75 - are there any major pitfalls doing it either way - hopefully someone has experience of this - Sorry if this is in the wrong bit of the forum
Cheers
Andy

pete davis does the register for the british lambretta archives so he will tell you what to do when he sees this thread, but from my understanding you will not be allowed to register the lui as a 75 as the frame numbers 20/8 are for a 50cc frame and thats what it will be registered with the dvla as.
there is nothing stopping you from putting the 75cc engine in, but inform your insurance and again dvla.
why not just put a 75cc kit onto the lui casing and keep the original engine numbers etc?

Hi
Sorry didn't realise Lui 50 cases were same as v75S- as Lui has 3 speed gearbox and Vega 4 speed - there is another slight complication as I was going to also convert the 75 Vega motor to Cometa spec - (have most of the parts inc tank) - do the lui cases have the internal bits to bolt the pump to?
Not worried about having a 75cc Lui with positive oil injection
Cheers
Andy

I've always wondered if you register it as a 75cc you will be required to have a dipped beam and brake light. I know that in general if not factory fitted you dont have to have them but the MOT requirements for 50's and 75s are different so I would not like to get caught out that way.

Anyway I would defo register it as a 50 and then change it.

the vega and lui cases are different,, you can though now buy cassa 75cc alloy cylinders that will give a lui a much needed help along in the speed department.
the lui case as far as i can remember (only had one for a couple of months around 7 years ago) can not be converted to oil injection.
the vega case can be converted, but i have never done this, nor would i attempt to do it, i'm sure someone will happily swap a cometa casing for a vega one.

The frame number is all that the DVLA are interested in and it is this which gives the scooter its identity. It wouldn't matter that you had a TV 200 engine in the 50 CL frame it would still say 50 CL on any logbook that is issued. In terms of which way to do it I would go for using the 75 engine when you register it, the V55/5 simply needs to show the correct engine number and the CC as 75 and use the 50 CL frame of course.

If you use the 50 engine and then change it over later this can be a problem with DVLA wanting extra paperwork.

Let me know if you need any further info and you can e-mail me at: BLAAuthentications@hotmail.co.uk