Need Some Help

[schneiderrd]

I need some help in determining the largest rear cog I can use with my current set up. I have a FSA 34-50 compact crank with Ultegra front and rear DRs. I am currently using a 12-25 cassette. I know that there is limit as to how large I can go on the cassette and still have things work right; I just don’t know how to calculate this.

Thanks

Richard Schneider

[Ken Robb]

I run 27 tooth cogs w/ 105, Ultegra, and DA Rds