Welcome! I have what I call a ‘not a gravel bike’ – and old Cannondale road bike fitted with 28mm Panaracer GravelKing SS tires, which is about the biggest tire I can get on it. I’ve ridden the local sections of that trail (Middlebrook > Millbank) and, as long as it’s not really, really wet (early spring mud), the bike was very happy. It’s a pretty nice trail in this section – flat with crushed limestone. Not too challenging at all.
I have not ridden the entire G2G trail, so I have no idea if this stretch is representative or not. My experience riding my set up is it’s fine on relatively firm surfaces like the crushed limestone or well-trafficed dirt roads. Where it falls down is in the really loose stuff – a just re-gravelled road, for example, has the bike dancing around quite a bit. The mud of early spring was do-able, but the 28 mm want to dig in rather than float along the top, so it was slow going.
But, for the stretch across the top of Waterloo, the G2G isn’t too challenging in my experience. If it does get looser/more challenging beyond that … well, I’ve found 28 mm tires aren’t as happy when the going gets loose and more technical.
