I've done both an '87 and currently a '91 400. Piece of cake. Late model stuff goes right on with some minor issues. I believe I had to drill for recessed brakes on the 87 maybe the bridge on the 91. I also had to file the slots on the 6600 Ultegra brake arms to drop the pads down a bit further. 400's are actually nice bikes the 87 was 531 and the 91 is Tru Temper RC2. It makes a great commuter as it has all the brazes ons for racks and fenders and the longer chain stays for heel clearance on bags. I never had to cold set either bike, a 130mm wheel fit in with minimal effort. I also feel that the value to upgrade is OK if you can pick up stuff reasonably. I'm riding a full 6600 10s Ultegra bike for under $1000 including the bike and accessories, while having parts to throw on other old bikes. I say go for it. I built mine with a lightly used group from Ebay and a new wheelset.

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