That is correct. No emissions sticker was used on the 1977 Yamaha DT100D. They did however use the battery sticker, located on the rear fender, under the seat. that sticker can be purchased here on the website or on the eBay store. We also have the emission sticker you mentioned for the 1978 Yamaha DT100E for sale on site/Ebay. All of the DT100 emission stickers from 1978-1983 were located on the rear fender next to the battery sticker.

In 1969, Yamaha released the 125 and 175 enduros. Those models were released in the USA every year, until 1977. Due to the new EPA regulations no 125 or 175 Enduros, were released that year, in the USA.

The USA GT/DT80 80 models were made from 1973-1983, but just like the 125 and 175 enduros, they dropped the enduro 80 model in 1977 only, due to the new EPA regulations.