i have a 72 tooth sproket and Im wanting to switch it with a 53 tooth sprocket... Only prob is the hole in the 53 sprokare smaller than the 72... and also not far enough apart.. Can I drill into the 53 sprocket and put new holes?
Did you buy it new? If so, can you exchange it for the correct size? If you try to modify it, and run into problems, it will be out of your pocket.
Getting to your question, yes, it can have the center hole opened up. You are going to want to use a drill press, at the very least. A lathe would be better. You can drill out the hole by hand, but there are no guarantees of success. It can be done, it's just not very pretty. Anything over about 1/2 inch is a real bear to drill by hand, period. Let alone, trying to hold any accuracy.
If you decide to go that route, you are going to need a good, sharp bit (preferably new), a drill with slow speed/high torque, and a good can of penetrating oil, like Liquid wrench, or PB Blaster. WD 40 will work, but it's really not a lubricant for steel.
Good Luck. Pat H.
