Modern Vespa

Had a go at fitting my SIP speedo today and came up against a few problems.

I have the speed sensor converter to replace the speedo cable but it doesn't look like it fits, does the part under the rubber seal come out? I can't seem to find a definitive answer but I have seen a mention of a top hat which could be the issue I have.

The other problem I have is finding a 12V source for the speedo to run. It has had the battery removed so is running AC, in the manual it says to find the headlight power wire, does this mean the wire going to the headlight switch?

I've given up for the day as I was getting frustrated and probably pissing a few people off as I have to have it running to find the right wires

I may also have another issue with the headlight switch itself but I'll save that for another day

That speedo sensor in the picture is used with a magnet that rotates with the wheel. Just use your original speedo cable.

12v source from the headlight is at the headlight and not the switch. Tap into the wire that goes to the headlight.

Good luck.

Yes, the part that's under the rubber seal slides right out. It should come out fairly easily. Maybe hook it with a dental pick or a small screwdriver to fish it out.

Original cable is knackered hence why I bought this one to solve any future issues with cables. Ironic that I'm struggling with it really

Thanks for wiring pointer, according to the wiring diagram I have that should be the purple wire but I'll have a test with the multimeter first Thanks I'll give that a go in a mo

Had some success, speed sensor is now in

What did you have to do? Going to be looking at mine today as I need to order one for mine to work.

Here's a pro tip...
that hex head screw that retains the metal backing plate for the speedo's rubber seal?...replace it with a socket head cap screw. It's easier to fit a "ball end" allen wrench than a socket or a wrench.

How have i missed this trick over the years....... nice suggestion....

if only i had had it 30 years ago i would not have skinned so many knuckles and uttered so many choice expletives

I couldn't get the top hat out of the housing. I needed a set of long reverse pliers really but ended up using all manner of picks and bits of wire and got there in the end. Amazing tip, why didn't I think of this myself before I put it all back together?!

I'll do it next time

Now just to get the speedo wiring itself sorted which I think I've figured out