I have a 14 tooth front sprocket. I'm wondering how much bigger I can safely go on the rear sprocket without needing a new chain???
i know for a 14/45 setup you need a 112 link chain
A 14/42 should be OK it moves axle forward about .2" from oem 16/39 position. A 14/45 should have a 112 link chain like Josh said above.
http://gstwins.com/gsboard/index.php?topic=44849.msg502495#msg502495