I searched so but didn't find much out there . I have a Riva girdled Head and I have 35domes now , The original owner used 32mm domes with race gas but replaced with 35's so I can run Pump gas. Well now maybe I should had left it alone because I am looking to going back to 32s. How hard is it to switch and is it common to switch to when your just riding the lake or racing. Any opinions and suggestion would be great, the real question is it difficult and is there anything I need to be sure to do when I attempt it.