Geez, 2 weeks & you want them to breed? They hardly know each other!
It can happen in two weeks, or it can take several months. Around a year ago I sold some dollar size silvers & golds to one of the better lfs. They spawned in their tank in less than 2 weeks. On the other hand, I have four 18 month old koi angels that have been in a 29 for 6 months with a known female dark marble without pairing. I started with five, one was getting pretty beaten up, and got put in a 55 with some larger angels. That one paired with a gold, and spawned a couple weeks ago. I just pulled a spawn tonight, their second. The angels in the 29 have yet to do anything, brokeback koi or something. There is another pair forming in the same 55, a silver & a gold veil, the silver is almost a super veil, both siblings from one of my earlier spawns. The koi are right next to them, they can watch & learn, but I guess they are slow learners.
Sometimes there is no rhyme or reason for pairing & spawning. Water changes with water a couple of degrees cooler, water changes with water from the tank of actively spawning pairs, increasing feeding & doing water changes daily, withholding food, letting the water evaporate & topping off to increase hardness, then doing water changes with cooler water & feeding like crazy are all things that I have tried with these koi. You may want to try some of these, they've worked for my other pairs.
As a last resort, this is what I'm trying;
http
/www.aquarticles.com/articles/breedi...%20seasons.html
Today was day 1, I've been meaning to get around to trying this, but I've been busy over the summer, it's tough hiding in the basement when the weather is nice. I've been running a nice low corner box filter the last 6 weeks, this will still operate when the tank is only 25% full. Something tells me this is going to be a nasty looking tank in a couple of weeks, I'll try to post some pics.