Hello all, my bike has 10speed mirage drivetrain, I love it with the exception of the cassette. Not enough low gear for me. I admit I'm still very new cycling but I'd love a little more low gear. I'm assuming my bike came with a short cage rear derailleur, and its ultradrive if that makes a difference. I found a couple of cassettes I'm interested in but I'd like to know of there will be compatability issues. I can only assume there will be. I have a standard compact crank, 50/34 and a 12/25 cassette now. I see there is a 13/29 and a 12/30 available. I'd love to get the 12/30 if it will work but I guess thats why I'm asking here. I really dont know what will work, can someone enlighten me?

The likelihood is that your present RD will work with either of those cassettes. You will need to adjust the b screw to the max
most likely and remember to add 2" (4 links) to the chain. Worst case, if you don't like the way it works is to spring for
a $20 wolftooth RD mount extender. FWIW a short cage 9spd DA on my recumbent shifts a 34t cassette without strain.

Have you taken it to the bike shop? A bike shop would be best for a job like this as it requires experience and special tools. It's possible you will need a different rear derailleur and it's probable that you will need a new chain. My guess is that the Mirage shifters will work. But instead if guessing, take it to the mechanic.

Agree, ^^ above^^ go to the bike shop..

a desert mirage is just the way the heat affects the light you see,

It really is not there.. well the Casino in Vegas may be there..

Try it and see. 10s tech specs from Campy suggest you should be just fine with a compact setup, short cage and going up to 30t rear sprocket.

https://www.campagnolo.com/media/fil...ev02_07_16.pdf

I'll probably make an appt with my shop, I dont want to get into to much trial and error at home. Hopefully I'll get lucky and get away with a cassette and a new chain.