'''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
All Shimano cranks with Allen head crank mounting bolts that I've ever seen use an 8mm allen key. BTW, get a long arm wrench. A standard L-key won't give you enough torque to remount the crank. Better yet, get an 8 mm socket bit so you can use a 3/8" or 1/2" square drive ratchet.