Modern Vespa

Hi everyone I know there is a specific wiki for the groan/moan/moo or fart that the vespa makes from time to time. But I could not find anyone else with my front brake problem. So my LX150 makes this sound when I cross a bump and it makes a "groan," "moo," or even a "fart"-like sound. It sounds like air pressure escaping from the engine. At the exact same time this happens, my front brake becomes stiff. The sound and the stiff brake only last for about 5 seconds. Has anyone else experienced something similar? Thank you

re noise:
FAQ: Why does my GTS groan/moan/moo or fart when off?

What do you mean about the brake getting stiff?

The front brake actually comes on? The brake lever gets stiff?

I don't know about the sound (though it may well be related), but I can say your brake should definitely not be impacted by bumps.

Is the brake line pinched or binding at all? When was the fluid last changed?

I know about the wiki, I mention it on my post, but the wiki does not talk about my brake lever stiffnes while doing the weird sound.

My front brake lever gets stiff while the bike makes the weird sound. Seems like the pressure on the brake system goes up suddenly or something weird is happening because once the sound ends everythings goes back to normal.

I will take it to the workshop, I got it brand new but is a 2021. I suspect the fuild has never been changed, but I thing the problem is not the fluid or the line because it would be a persisten problem.

It's nothing to do with the Evap system (the Wiki thing). The noise is almost certainly mechanical, not 'atmospheric'.

Check your front brake caliper is firmly attached with both bolts.

Check the front brake line doesn't get pinched by the suspension over the bump.

They said "fart like". I can't think of a "mechanical" thing on a scoot that would be fart like?

Any thoughts?

But i do appreciate the timing coincidence

Note: I'm shorthanding evap noises to include fuel tank venting on bikes without evap as i don't know if they have an evap in theirs.

Hi guys, quick update. It seems I was confusing the sound... the sound comes from the front brake. I suspect the abs unit is faulty. I tried braking hard with front brake, it activated the ABS and it made the same noice. It makes sense that the front brake gets stiff when I hear the sound because it has something to do with the front abs brake. I will update once I take it to the workshop.