On Monday, February 18, 2019 at 7:30:06 AM UTC-5, John McLaughlin wrote:
The undercarriage lever seems reluctant to stay in it's detent with the
wheel down - it'll pop out with the lightest touch and the wheel has been
known to retract, going over a bump.

One option is to push a wooden wedge against the lever, to hold it in
place,
but does anyone know if there's a better fix available? I believe the
Ventus
3 has a spring to hold the lever outboard - is that an option for fitting
to the
2?

I have to admit that I have not worked on a Ventus undercarriage but I worked on a good number of other ones. They all have one thing in common and that is a classic 'over-center' design, which keeps the struts locked in place when the gear is extended and loaded. The actuating levers and rods are most likely never meant to bear the loads imparted onto the gear mechanism upon landing!
I would recommend you check the degree of over-center, which may be adjustable. Also, in most all cases, there is some kind of a spring or gas strut involved, which holds the over-center in position. Using a door stopper may make the symptoms go away but it does not fix the problem.

Uli
'AS'