We are running the same strategy. I have a spreadsheet of costs and break it down into the number of 'slave hours' I have banked up.Tell you another good one, #1 son changing gears, standing up, cranking and accelerating, clunk-clunk-clunk
Shouted at him numerous times, telling him he was destroying the cassette and chain. Explained the old saying of 'Change gears like your cassette teeth were made of glass' with no avail.
Cassette fucked, lost a gravity enduro because of it. Gets a $250 cassette as part of his chrissy presents last year... hasnt shifted under load since.
They have had many warnings in the last year, I will not pay or replace parts for laziness, show off's or percieved cool shit that wears out a bike or parts.
This laziness specifically is about not pumping up tyres before every ride, then denting alu or smashing carbon rims.
Like your kid doing a burnout to show off then coming with his hand out for new tyres.
I think they are starting to get it
Mine is recovering from a broken shoulder at the moment as a result of showing off, now the agreement is that if he further injures himself while riding in the recovery period he forfeits the ownership of his bike to me.
We all complain about the costs but I would rather they were outside doing something than playing computer games.