The frame is powder coated and I have the engine back together with the exception of the top end which lightens the engine making it easier to install it in the frame. I can install the top end easily with the engine in the frame.

When I get the engine in the frame it’s a milestone as from now on parts are going together to create the motorcycle instead of coming off. 🙂

Parts

I replaced the engine studs, washers, and nuts with stainless steel ones I got in the R80ST stainless steel hardware kit I bought from Motoworks BMW.

Video

This video shows how I install the engine in the frame.

VIDEO: 1983 BMW R80ST Install Engine In Frame

Engine Mounting Hardware

The front engine stud is longer than the rear on the R80ST since the engine guards mount on the front engine studs. The front stud is 315 mm and the rear is 298 mm.

There are  bushings that fit between the engine block and the frame. The rear ones are the same size (6 mm thick). The right front is the same size as the rear, but the left front is thicker (9 mm thick). The studs are secured with nuts, wave washers and flat washers.

Protecting Powder Coated Frame

I had the frame powder coated.

NOTE:
Check the inside of the holes in the frame that the engine studs go through for any power coat. If there is some, sand it off as the clearance is pretty tight between the engine stud bushings and the frame.

I use some foam packing sheets to wrap the tubes so I won’t ding the powder coat when I put the engine inside the frame.

Putting The Engine Inside The Frame

The engine is front heavy so I put a 2×4 under the timing cover. I also put a 2×4 under the front of the frame to keep it level.

I bend my knees to pick up the engine so I won’t hurt my back. It likely weights 60-70 pounds. I tilt the top of the engine toward me to slide it under the spine tube and then tilt it back and set it down.

I slide the frame backward so the rear hole in the engine block is close to the rear hole in the frame.

There is a tube the slides between the two bushings cast into the engine block that the rear engine stud slides through.

I found it was easier to tip the frame and engine forward so I can maneuver the frame until the rear engine stud hole is close to the hole in the engine block. I slide the rear engine stud (the shorter one) through the frame and catch the rear spacer on it and then tilt the frame to align the holes and slide the rear engine stud into the hole in the engine block. I use a plastic hammer to tap it through the hole until it’s just protruding out the other side of the engine block. I push it back so it’s flush with the block, insert the other rear bushing and tap it through the bushing and the hole in the frame.

I repeat this procedure for the front engine stud making sure I put the thicker bushing on the left side and the thin one on the right side.

NOTE:
Left and right are traditionally from the perspective of sitting on the bike. So they are reversed in the photos below.

I pick up the frame by the spine tube and put the frame and engine on my portable motorcycle lift on top of a piece of plywood that sits under the oil pan. This distributes the weight across the entire oil pan it doesn’t get damaged.

I secure the frame with tie down straps and use pieces of the foam packing material under the straps to protect the powder coat. I use the 2×4 under the timing cover to support the front of the engine to stabilize it.

I am going to leave the engine stud nuts loose for now as the engine guards mount on the front studs.