Modern Vespa

We've all heard of the dreaded 'notch' issue. I had it on my 1st MP3 from 2009. It's not a nice feeling and it stopped me from driving it.

So yesterday, my 2016 MP3 felt unbalanced going down the road. I tried doing some S turns - nope. I had this weird feeling that I was going to tip over. My mind immediately thought 'NOTCH'. But I couldn't feel any notch unlike my other bike.

Turns out I had 15 PSI on the right front tire and 35 on the left! Set both to 29 this morning and like magic my bike was back.

The moral of this story should be obvious. Tires can make all the difference in stability and making sure they are in good, working condition should be your first priority and your first check when you have front-end-stability issues.

2016 and later MP3s aren't as well known for the notch issues seen in the earlier models. But like all bikes, and especially trikes, it still happens especially if the first check-up lube is neglected.

Seems odd for tire pressures to be so far off? Are you sure you didn't pick up a nail?

Yeah pretty well known for a decade that uneven tire pressure on the fronts is squirrely but thanks for brining it up for those that dont know.

Also the bike kinda "counter-steers" a bit in straight parts of your trip and thus is willing to turn to the opposite way of underinflated tire. Kinda the right tire is low in pressure and thus lower in shape, so the handlebar is a just a bit turned to the right as if you pushed the left grip, so the bike tries to steer to the left.

Thats a heck of a difference in tyre pressures and why did you have 35psi in the left or is that a miss type, Can i assume 29psi is for the 13" front tyres as the 12"fronts are 23 psi and as i changed my fuoco/mp3 500 to 13" fronts i'm still running them at 23psi and seem ok.

29 psi (2 bar) is what my 2016 manual states for the front tires.

Think i will up my tyre pressures from 23 to 29 and see if it improves handling.