Not as tidy looking as the stock 28t, but bigger chainrings are available thru the Seller of those Patterson metros
28/'45'
Schlumpf speed drive is another 2 gear ratio overdrive transmission .. they offer a 110 5 bolt spider model. for 34t or larger chainrings..
34/'54'
Last edited by fietsbob; 08-04-15 at 09:38 AM.