What is the difference in the chain rings that are used on a triple gear crank set vs the ones used on a double gear crank set?
I just bought what I thought were new chain rings for my 3 speed Ultera 6500/6503 crank and when they arrived, they are both marked as being for a double.

Are the chain rings the same? I went to Shimano's Website looking for information but could not find anything specific. It did list the chain rings that I have by part number and said they were for a 6500/6503 Ultegra 9-speed, but it did not mention which front set up they can be used on.

Wayne

A 42 tooth ring from a double does not need ramps and pins to lift the chain up from a smaller ring. A 42 tooth ring from a triple does need the ramps/pins.

And then further, sets of rings have their shifting helpers aligned between the rings.

https://techdocs.shimano.com/media/te...9830611835.pdf

https://techdocs.shimano.com/media/te...9830611836.pdf

Way Back the differences, were less,
Indexing benefits from shifting ramps , lifting pins,
. and shortened tooth tips, to shift early.
friction shifting , is an over shift and adjust back to re center late shifting scheme..

so triple middle rings on the inside face of those chainrings is like the inside face of outer chainrings..
Either feature laden... or not..