I actually used the inserts from a park headset press. I removed them from the press, inserted them in the cups, and then tapped on the inserts with a rubber mallet, driving the cups into the headtube. You'd need one heck of a length of all thread for this bike. I'm not sure how long the headtube on it is, but it is longer than the 62/63cm road bikes I ride-- which my Park press can barely handle. The key is getting the cups in straight-- which, IME, you must watch no matter the tool you are using.

I had a nice sealed bearing headset I was going to use, but once I'd tapped out the cups and crown race of the old one and measured it, I realized the problem. I believe the JIS standard is still used on some very low end bikes (ie Roadmasters from WalMart, etc.), but it is practically obsolete otherwise, and replacement options are limited. I was lucky I had bought a box of headset parts cheap at a bikeshop going out of business sale that contained several JIS headsets of reasonable quality. Phew.

One has to wonder if other BD bikes share this issue. Headsets aren't something the average customer thinks much about. Here on this thread, enough of us like to tinker so that we would think about it. I thought about it from practically the instant I opened to Nano's box. If BD can shave a buck off the cost of a bike, they'd probably rather do it on something that the customer doesn't notice.

Here is a link to the Velo Orange JIS headset. I'm currently using two Velo Orange headsets-- the needle bearing is on my Serotta track bike, and the sealed bearing unit is on my Serotta road bike. Their headsets are pretty nice, although the JIS style one is the most basic of any of their units. I would ask VO if this a pure JIS headset (27 crown race, 30 cup size). During the eighties, there were a lot of bikes that used a mixed standard (27 crown race, 30.2 cup size). I've installed the VO unit on a bike before-- an Asian made Bianchi-- but I cannot, for the life of me remember what the cup size was.