Modern Vespa

I picked up a px125 recently however the Speedo is not working but I noticed the cable is very loose going into the hub drive. Question is how do you get access to tighten up the small bolt retaining the clip that secures the cable?
Thanks

You need a thin open-end wrench, 8mm if I'm correct. The space is very limited, so it's slow going turning the wrench over and moving the bolt in small increments. The rubber grommet under the metal plate might be shot. That's usually why the cable works its way out.

As I am finding out, the speedometer arrangement isn't very sturdy or reliable. Besides the possibility of the cable pulling out, they have been known to break and the worm gear that drives the cable tends to get chewed up. I replaced the cable and gear on my Stella recently and got a couple rides out of it before the gear got chewed up again. I had removed the hub, cleaned and greased the splines and followed any directions I could find to the letter. I really hate putting time and money into something that won't work.

Not having a working speedometer is one of my pet peeves. It just feels shoddy. Good luck.

It is a PITA. I have done it probably 3 or 4 times. You can do it easier with thin socket and a small 1/4 wrench. There are also flexible extensions that bend and gives you better angles. While you are at it take a good look at the plastic gear inside the hub, you will need to pull it out with tweezers.

If the gear worm goes in upside down (in other words, wrong) it will get chewed up. I'm not saying previous posters did that, but it's nevertheless a possibility. The PX also has two types of gear worm, one white and one grey, depending on the size. You need the right one.

I once bought some V50 NOS black speedometer worm gears for my V90 thinking the bikes for this are interchangeable. Not so. V90 is red and smaller diameter; V50 is black and bigger diameter. All I had to do was check the parts book beforehand. Now I have these NOS black ones sitting there. Anyone need one?

LOL, I respect your civility, but in all honesty, yes could well have done and will check. One end has a cable shaped opening and the other does not, I am Mr McGoo when it comes to widgets like that.

Haha. I ruined several at first. I kept asking myself why it would destroy itself when I spun the wheel backwards. Then I realized it wasn't destroying itself; I was destroying it.

Ok. I thought I had it right . Only one end looks like the cable will go in, but I will have a closer look. I always buy 3 of those types of hits: the one I lose, the one I abuse and the one I use.

On the speedometer gear, the bigger hole faces out toward the cable. Robot has a video that covers this pretty well. It is for a drum brake hub, but most of it is transferable to a disc brake hub.

Speedo gear at 59:30, speedo cable at 107.00, hub install at 110:00.

https://www.youtube.com/watch?v=_dRLspdddPA

Thank you.

That's how I did it. One end has a square hole that fits the cable. The other end has a hole that is obvious too small for the cable. Drive gear on the hub cleaned and freshly greased. Gear looks identical to the one I removed. Gear on my p200 is fatter. I'm stumped, but I will have a look at the video.