700c on a 27" frame... what the biggest 700c tyres that can fit?

I reckon a better look is the Paul Thumbie solution:

Barcon’s traditionally mounted look stupid in my opinion :slight_smile:

Sure, but add up the price. And if your only using 5 or 6 speeds the plain old $12usd ratcheting thumbshifter is more than enough.

I’ll try another route… stem mounted shifters buta de luxe version