Flatbar Road 10 spd Shimano Sram combos
I know this topic has been covered in various different ways, but I STILL have a question about the incompatibility of sram and shimano drivetrains.
Specifically, I am building a second 10 spd flatbar road bike and I'm scoping out rapid-fire shifter options. For my first flatbar road bike build I bought the shimano SL-R770 10 speed road shifters. They are running on a complete sram rival group. That's right, a sram rival front and rear derailleur with shimano shifters. So you're not supposed to be able to mix shimano shifters with sram derailleurs (or vice versa) because the cable ratios are different, but I did anyway and it works FANTASTICALLY! Can anybody explain that for me because I can't?
Now for the second bike I am again going 10 speed (because the wheels I have require that). I have a 105 rear der and either the FD-R770 (that was supposedly required with those shimano shifters) or a tiagra front to use. So the obvious thing to do is buy another set of the SL-R770, but those are $150 (with shipping) and the Sram 10spd flatbar road shifters are only $80. So I'd prefer the Sram, but I'm worried about compatibility...but the other way works like butter on a bald monkey for the first bike so I'm thinking it might actually work, but I don't know how it could.
You might think I'd get the Sram shifters and swap them with the first bike so each bike would be sram/shimano specific, but if you had a bike shifting that sweet you wouldn't want to mess with the inexplicable magic mojo either.
Any helpful info or advice? Any experiences of others throwing caution (and instructions) to the wind and mixing these components? Thanks in advance.