A bike that's the size of a tennis ball would be about the right size for a wasp, although I would have thought that a wasp would prefer to ride a Vespa.
the wasps up here can even drive cars count,
i left the loft window open for about 3 days and never noticed it when opening it and it is just below it. I just noticed it when i had closed it there is no sign of life about it so may leave it a couple days before removing it to make sure they've gone
They have been working on that for weeks and will carry on working on it, it will get much much bigger. Deal with it now before it starts causing problems with thousands of wasps!