Originally Posted by
maddog34
Bore gauges are EXPENSIVE and rarely seen in anything but Machine shops.
You've not looked on Ali Express, have you? 18-35 mm dial bore gauge
￡34.46 with free shipping (that's not the cheapest one). Almost certainly not toolmaker quality, but probably plenty good for a bike workshop. I may try one myself, I've had some good stuff from Ali Express (and some total junk).