But yes is the answer. Purchase, borrow the correct bike for the event and its all ' Yes Man'.
Just another way of saying No.
We're stuck in this mentality of "more rules is better", and "stricter enforcement will fix it", when the opposite is true.
Quibbling over whether a modified RM-C swing arm is pre-78 is legal, or whether you need the operationally-identical optional RM-B alloy arm is a joke.
Say Yes, and all the bullshit goes away - with no actual bad points.
Wanting to kick a handful of 1985/86 models out of a non-competitive event achieves nothing but will surely drive people away. Continue to Say Yes to them (even quietly), and the problems go away.
The same is repeated time and again in the world of old dirt bikes: Metisse down tubes, 1974.5 KTM shock mounts, Yamaha TLS front brakes/fork legs, CZ sprocket mounting, 75 CR125 barrels, etc etc...
They're minor details in the big picture, but we spend (or have spent) WAAAAY too much time and effort worrying about them - to no benefit to anyone.
The main purpose of the VMX/Vinduro worlds should be
riding and enjoying old bikes.Instead, we've become an army of bush lawyers, all ready to mutter under our breaths about things that are "not right", while knowing that the transgression is trivial and has absolutely no bearing on the outcome of the race (or non-competitive event, FFS).
There's been a couple of too-new bikes turn up to Retro rounds over the last couple of years. The organisers have Said Yes (but not to score championship points), knowing full well that the bikes weren't quite right.
And guess what? There was no bad point - another entry fee for the organisers, another membership for the club, another bike on the track, another smiling face at the end of the day. An inclusive attitude, not an exclusive one.
Even the old bogey man of "what if they ruin my race" has never eventuated, despite the "illegal bikes" being right up near the front most of the time (because they had competent riders, not because the CR125 had a HPP barrel on it...).
I'm not saying that we want to see 12" travel on pre-75 bikes, but there's just so much bullshit over nothing.
I did the CAMS scrutineering course many years ago. The trainer said something very important:
"You job is not to find faults. Your job is to get as many safe and fair cars onto the track as possible".
We have plenty of VMX scrutineers who understand this - the rot within comes from everywhere, certainly not just from (some) scrutineers.