It should be relatively easy to make letters that resemble GiraGira letters. Find a suitable base font. This would be a monoline sans with rounded ends that has somewhat similar letters, for example

adjust widths and other characteristics where needed, and edit strokes on the distinctive letters, such as _R_, _E_, _A_, _K_, and _Y_, plus the additional letters shown at the website.
To get a matching weight to GiraGira I did a 50-50 blend of Simpliciter Sans Regular and Simpliciter Sans Bold http://www.myfonts.com/fonts/cercurius/simpliciter-sans/
The GiraGira letters seem to have been produced by a Dutch designer, while Simpliciter Sans is by a Swede. Some searching might reveal a base font that is a closer match.
DISCLAIMER: Some of the letters form part of a company name. There may be legal issues in using exact copies.
Don
p.s. Go to the company website and find out some fascinating information on track racing bikes. Don't miss the parts FAQ. The company seems to be interested in international sales, they take payment in US$, Euro, British Pound, Canadian $, and Australian $.