Now available on the site. These are American made, machined from 6061 T-6 aluminum with grade 8 equivalent bolts and instructions to make the change to a single bolt setup. Seen here, the 50cc adapter. 4.0 ounces weight, subtract the old long bolts and the prop shaft for 1.8 ounces you have a net gain of about 2.2 ounces on the setup. The adapter measures 7/8 of an inch in thickness, so when you have mounted it your engine will go back 7/8 of an inch to keep the same prop line to the cowl. Thhis will require shorter standoffs and it will make up for a portion of the extra weight of the setup. The 50cc adapter was released over the summer. There are a few out there with regular daily use....no issues. 50cc bolt is 10mm and tapped for a 10/32 spinner bolt. No more looking for the drill jig.... One possible large benefit is that when the engine moves back 7/8 of an inch and so will the muffler....in some tightly cowled setups this can help with how much of the cowl that is required to hack up to accommodate a muffler (usually side dump) setup. Located in the shopping cart here. http://www.shop.kavarootusa.com/product.sc?productId=30 Tutorial to follow.