[Lionheart]

The bike and the rider in the above pic look to scale. Ghosty and his bike do not. Something is off. I've bought a lot of 1:18 bikes and cars, and with very few exceptions they are all too small for the figures (hence why figures don't really fit in 1:18 cars, and stand too tall next to them). The difference isn't huge, but if there was an 'adult', 'junior' and 'infant' version, they always look like adults on the junior version if you know what I mean.

I think what Golbug said is right - maybe many of the 1:18 vehicles are slightly underscaled. My eye prefers slightly over to slightly under if the scale isn't right so I'm also emphasising a prejudice I have for scaling with figures.

I just looked at the bike that came with Indiana Jones Mutt. The bike seems scaled well for the figure and is more or less the same scale as other 1:18 bikes I have. I see that the Indiana Jones figures are just a little under 4 inches, but that MU and Joe are about 4 1/2 inches tall, and they seem too big for the bikes. It might be a combination of figures larger than 4 inches and some vehicles scaled slightly under creating this.