Craig Hockmeyer, proprietor of Craig’s Cycles on State Road in Vineyard Haven, will demonstrate how to do essential bicycle maintenance and repair on Tuesday, Sept. 30, at 7 p.m. at the Vineyard Haven Public Library.

Called Easy as Riding a Bike, the presentation will use environmental activist Mr. Hockmeyer’s own green machine, and there will be plenty of time for questions.

Mr. Hockmeyer has been maintaining and repairing bikes on Martha’s Vineyard since 1978, when he worked at Borg’s Bike Rental. In 1989 he opened Bike Doctor, a bike house-call service. And in 2000 he opened his current shop. His real interest is in putting bikes back together when possible.