My bike has two disc brakes instead of v-brakes so my wheel hubs have flanges that extend outwards in order to hold the disc in place. Unfortunately, this keeps me from putting the rear sprocket on the wheel... Are these wheel hub pieces generally removable or do I need to either get the disc brake sprocket adapter or a new rear wheel? I would prefer the sprocket adapter but I didn't get any response from King Sales and Service when I left a message about their top hat adapter. Is there anyone else who can make me a sprocket? Anyway, here is a picture which will hopefully help illustrate the problem... Thanks.