Modern Vespa

Hi guys,

It's my project again. This time I need some help with another conversion I am trying to make on my LX project. I want to switch from the classic dashboard of the 150LX to a new dash, specifically the electronic dash made by SIP.

Now, my main issue is SIP doesn't make that dash for the LX, for reasons unknown to me, as they are doing electronic dashes for PX and even older models, not to mention LX was quite a good selling model in its days and is still made for the asian market.

But. They are doing a dash for the GT, early 03-06 carburetted GT's. As far as I know the dash is virtually identical as shape and size with the LX one (I had my dash window cracked and I replaced it with a GT one I think, as it has the screw setting of the GT - it came from a scrapyard so I am not 100% sure), and as such I think it should fit in the LX handlebar cover as far as the opening goes (wouldn't mind for a confirmation).

I want to change to it for esthetical reasons ( I want black backlit dials) and technical reasons, as I'd really love to have the extra info provided by the electronic tach, voltage meter and all the rest of the gizmos it has.

Here come the tech kinks of the project that I could use some help with, if someone has any ideas. For the record my LX is currently completely dissasembled so I can't even look to estimate if things could fit. I have already asked SIP tech guys but they are taking their time to respond.

First of all I am completely unsure of the height (thickness) of the new SIP piece compared to the LX one, and I have no idea what clearance is on an LX between the dash and the metallic part of the handlebar (as I told you, mine is dissasembled). I am not worried much about the dash itself as I see it's pretty thin but more about the electrical coupling they are using. Also there's an issue about the speedometer coupling position compared to the one on the LX.

Second, SIP reccomends for the GT to replace the original cable with the GTS cable PI56306R in order for the speedometer to work. The LX 150 is using the same worm drive and lower mount as the GT/GTS so the lower part fits, but the upper receiver is different, 10mm thread on the LX, 12 mm thread on the GTS so I cannot use the old cable from the LX. I could use the GTS cable they reccomend for the GT but it's about 10cm (4 inches) longer than the LX cable. Anyone experienced enough to tell me if there would be any issues if the cable is 10cm longer (not esthetical, functional wise)? I can go the extra mile to try to shorten the cable sleeve if really needed and use the inner cable from the LX but it would mean really, really, big complications that I am trying to avoid. One other solution would be to try to replace the coupling on the dashboard from my old one to the SIP dashboard, I know it would forfeit my warranty but if it was possible I could not care less.

Third, electrical part. I know water temp will not work, as the LX is air cooled (also the engine check light will not work, the LX doesn't have one, not sure if early model, carburetted GT's did, that is also a question) but, as I see, they put a spark plug temp sensor on it so I think I can adapt a Koso oil temp sensor to check engine temperature, I care less of the spark plug temp than if the engine is cold or hot, and if I put the oil temp sensor on the water temp it will probably warn hi-temp all the time. Rest of the wiring I think it should work as I see the original couples of the early GT's are looking similar to the LX.