Paul@MCP

Info I gave is wrong now according to not so helpful customer. I now have no idea what rear sprog fits a US import DT400. All I learned is that the centre hole is far smaller. If anyone had dimensions, I'd like to help if anyone needs one

There are 2 types of rear sprockets for the DT400, one has a 62mm centre and the other a 152mm centre. The 62mm one is for the US market obviously including US imports into the UK. Standard 43 Toothed Rear Sprocket Yamaha DT400 1975-77 Sprocket Yamaha DT400 1975-77 (Rear Standard) Please Note: 152mm Centre - See Image Use this if you need 62mm version Sprocket Yamaha DT250 1975-76 (Rear) Hope this helps B'rgrds Paul Motorcycle Products Ltd http://www.motorcycleproducts.co.uk/catalogue/yamaha-motorcycle-parts.html