I don't think that the SA 8 speed is suitable for a bike with 27" wheels. The gearing will be too tall. It was designed for a bike with 20" wheels. The S-RF3 right below it on the page is a perfect fit for a bike with 27" wheels and 120" spacing. My Carlton is a conversion from an old 10 speed to a S-RF3 three speed. I got the hub for $63 from aebike.com and had a local shop build the wheels. It's the bike I ride the most because it's fun. It was a single speed first, and that was fun, but not as practical.