I bought a chainglider a few months ago but couldn't use it because I didn't know you had to use steel chainrings as they are thinner. My problem is that my cranks have 104bcd and I can't find any steel chainrings in 42t with a 104bcd. I'm considering buying a new chainset
http://spacycles.co.uk/products.php?plid=m2b0s109p3051 so I can use surlys chainrings but would prefer not to have the expense. Any ideas?