I suck, new road bike only has 2 big rings up front, could I put a Shimano Mountain Bike Cassette 11-32 on it?
Assuming the shifters are 9-speed (as I assume your MTB cassette is) and assuming you have a long-cage rear derailleur (which is unlikely), and another chain (it’ll need to be longer), yes, it will work.
Can you make do with a 12/27 road cassette?
Need more info.
Shimano? 9/10?
Campy?
If 9spd, you “could” change to an XTR rear derailuer. Although, I’ve personally seen an 11-32 on a Cannondale CX bike with a short cage Ultegra 9spd and it rode for 126 miles (HHH)…but the tech manual says there isn’t enough clearance.
Post more specifics. Have you tried a 12-27 (assuming Shimano)?
How about a compact crankset with a 12-27 cassette?
That will get you climbing easier.
I’ve put that on a road bike before for 6 gap century in GA but did have to add a xtr rear der.
O
You would need at least a Medium cage rear Der…but yes.