Originally Posted by
mikey_
another excellent idea: 52 tooth chainrings are on ebay for $10!!! And it looks like these are mainly interchangeable (just by looking at the numbers of bolts). Is there anything else to look for as far as compatibility?
You need to match both the number of bolts (5 for your crank I'm pretty sure.) and the "bolt circle diameter" (BCD) which is most likely 110 mm on your crank. Finally, you have to be sure your chainrings really do bolt on and are not permanantly riveted. Many low cost cranks are riveted together and the chainrings can't be removed or changed.
Also, you will most likely need a new chain for the larger chainring and a putting new chain on an old freewheel is a sure way to get skipping on the cogs. So, plan on a new freewheel too. You are into way more than $10 at that point.