Quote Originally Posted by wbute View Post
That was the same as the Japanese dirt bike manufacturers method for getting dirt bikes through ADR rules during the 90's. Honda liked to restrict the inlet manifold, (Yamaha used a washer welded in the header pipe as well)and a bung in the muffler with a 10mm hole. Plus a restricter in the airbox inlet. Then geared them to the moon so they were quieter for the ride by noise test. The dealers pulled them all out if you payed extra at delivery.
I remember removing those from IT490's when we brought them in the '80s.

Mauser