To add to the mix, I'm now also producing a Chromoly 4140 Hardened Rockwell 36C front sprocket for the stock 520 chain. These sprockets are hard clear through, not case hardened as most front sprockets are. This means it'll last a LOT longer. Going up to a 16T front is basically about the same as dropping 3 teeth from the rear. With the stock 15/45 gear ratio you have a 3.00 ratio. With a 16T front, this takes you to a 2.813 gear ratio, and still uses the stock 112 link chain. You can see the gear ratios and chain lengths for various sprocket gear ratio configurations here:
https://docs.google.com/spreadsheets/d/1T42Kjs53Xbad4d_krrIw5OPAEve9NntuLEwNRPkrnOY
These sprockets are made by yours truly on the Formula390 Vertical Machining Center. That means that they are made here in the USA, with 4140 Chromoly Steel which is also produced here in the USA.
Formula390 Sprockets Page
https://docs.google.com/spreadsheets/d/1T42Kjs53Xbad4d_krrIw5OPAEve9NntuLEwNRPkrnOY
These sprockets are made by yours truly on the Formula390 Vertical Machining Center. That means that they are made here in the USA, with 4140 Chromoly Steel which is also produced here in the USA.
Formula390 Sprockets Page
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