46-34 Compact with 12-27 Cassette

[aide]

For years I've had a Shimano 50-34 Compact with a 12-27 Cassette.

The cassette is a 12, 13, 14, 15, 16, 17, 19, 21, 24, 27.

I always struggled with the 50/17 and 50/19 combinations.

I spend most of my time on the flat in those two gears, but I would spin out of the 17 and found it difficult to stay in the 19.

After Easter I decided to get a new chain-set and tried to get a cassette with a 17, 18, 19 but couldn't find one,

Not wanting to get a new 11 speed group-set, I found this website:
http://www.bikecalc.com/gear_ratios and realised that:-
50/19 = 46/17
50/18 = 46/16
50/17 = 46/15

I fitted a 46 chainring and now I have the missing 50/18 ratio

The only downside is you loose the 50/12, however a 46/12 = 50/13 so it's only one cog that I rarely use.