The Classic Twelve.


The original twelve custom designs that have been on offer for the last thirteen years.

They are available in pretty much any tooth count up to and including 96t......the minimum number of teeth on the chainring will depend on bolt circle diameter (BCD).

I can machine these in almost every  BCD ever produced.

My sample photos are of 5 bolt designs because they by far the most popular, but these designs are definitely available in three and four bolt patterns.

Some of the Details get lost as the tooth Count goes up. The shape and proportions change, depending on tooth count  and the bolt pattern. I have some specific designs that are proportioned for bigger sizes above 60t .


Australian made Custom Bespoke Chainring Design BCD
Design One

Australian made Custom Bespoke Chainring Design BCD
Design Three

Australian made Custom Bespoke Chainring Design BCD
Design Five

Australian made Custom Bespoke Chainring Design BCD
Design Seven

Australian made Custom Bespoke Chainring Design BCD
Design Nine

Australian made Custom Bespoke Chainring Design BCD
Design Eleven
Australian made Custom Bespoke Chainring Design BCD
Design Two

Australian made Custom Bespoke Chainring Design BCD
Design Four

Australian made Custom Bespoke Chainring Design BCD
Design Six

Australian made Custom Bespoke Chainring Design BCD
Design Eight

Australian made Custom Bespoke Chainring Design BCD
Design Ten

Australian made Custom Bespoke Chainring Design BCD
Design Twelve




About.....


Cycleunderground has been around for over 22 years.

A lot of customers are surprised to find out that it is a one man machining and fabrication shop.

My name is John Bosevski and I have been servicing, repairing bicycles and building  frames, tools and bits for bikes for over 30 years.

I now concentrate on my components and tools and slowly develop new product and tooling to increase my offerings.

I prefer to concentrate on the bespoke side of bicycles, putting my effort towards products and tools that have been forgotten or overlooked.

 My workshop can be found in Taren Point,  Sydney,  Australia.