I have 5 inch rotors now and want to go to 8 inch rotors.
Am I going to void warranty? Cause a failure somewhere else?
Depends on the type of brake and type of bike.
Larger diameter rotors put more stress on the bikes frame and fork, creating a greater chance of failure. If you bike came stock with 5 inch rotors, there is a good chance it is not designed/capable of handling 8 inch rotors.
Thought that would be the case. Just have to get better at using the 5 inch rotors.
That's a big increase in power. Are you sure you need it?
Axle Standards Explained
6" rotors maybe?
What is the bike?
Hell is eternally climbing manzanita trail on your singlespeed.