Originally Posted by
HillRider
Which Tarmac model do you have and what is it's current crank and bottom bracket? The conversion is practical but which replacement crank and/or bottom bracket type depends on what you now have.
Also, depending on what you have now, you might consider a different cassette, and/or a compact crankset. Using a compact crankset would be easier than installing a triple; simply swapping in a cassette would be a *lot* easier than a triple.