1983 BMW R80ST Install Engine Top End

The 1983 R80ST top end is the same as the 1983 R100RS with the exception of a smaller cylinder bore, piston and rings. I already thoroughly documented installing the engine top end for the 1983 R100RS, so I reuses a lot of that material as appropriate in the documentation and the summary video.

Here is the document and video links.

VIDEO: 1983 BMW R80ST Install Engine Top End

Here is what I started with and the final result.

The Engine Before I Removed The Top End

The Engine Before I Removed The Top End

The cylinders and heads were vapor blasted and I hand cleaned the engine block. I repainted the inner timing cover and top engine cover and had the frame powder coated.

Here is the engine with the top end installed. I put shop rags in the exhaust and intake ports of the heads to prevent anything from getting inside. I also put red tape on the temporary spark plugs and on the dip stick to alert me that I need to install new plugs and oil before I start the engine.

What All Done Looks Like

What All Done Looks Like

What All Done Looks Like

What All Done Looks Like

1983 BMW R80ST Install Engine In The Frame

At last, I get to start putting this motorcycle back together. Every time I install an engine in the frame it’s a milestone. Instead of taking things apart, I am starting down the road to getting it all back together again :-).

Here is a link to the documentation and the video I shot.

VIDEO: 1983 BMW R80ST Install Engine In Frame

I had the frame powder coated.

Powder Coated Frame

Powder Coated 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.

Frame Protected With Foam Sheets

Frame Protected With Foam Sheets

The top is off the engine so it’s lighter and easier to install in the frame.

Engine Supported With 2x4

Engine Supported With 2×4

Engine Inside Frame

Engine Inside Frame

This is the hardware used to mount the engine in the frame.

Engine Mounting Hardware

Engine Mounting Hardware

It’s mounted on my portable motorcycle lift ready to install the top end.

Frame & Engine Mounted On Portable Motorcycle Lift

Frame & Engine Mounted On Portable Motorcycle Lift

 

1983 BMW R80ST Refinish, Lace And True Wheels

The R80ST has spoked wheels front and rear. In order to refinish the wheels using vapor blasting, I remove the spokes. This let me assess the condition of the spokes and spoke nipples so I can decide if I can keep most of them, or they need to be replaced.

On the rear wheel only 17 out of 40 spokes weren’t bent or rusted and only 8 spoke nipples were not damaged. On the front wheel every spoke was bent. So I replace all the spokes with stainless steel spokes and install new plated brass nipples.

This documents shows how I do this work.

And this video shows the techniques I use in more detail.

VIDEO: 1983 BMW R80ST Lace The Spokes And True The Wheels

Here is what I started with.

Front Wheel-Before

Front Wheel-Before

Front Wheel-Before

Front Wheel-Before

Rear Wheel Before

Rear Wheel Before

Rear Wheel Before

Rear Wheel Before

And here is what the wheels look like after refinishing them and lacing and truing the wheels with new stainless steel spokes.

What All Done Looks Like

What All Done Looks Like

1983 BMW R80ST Replace Wheel Bearings & Set Bearing Pre-Load

Before I install new stainless steel spokes and chrome plated brass spoke nipples, I replace the front wheel bearings. The rear wheel does not have wheel bearings. Instead it is mounted directly to the rear drive. Since the rear wheel does not have an axle, there is no need for wheel bearings.

Here is a link to the documentation on how I do this work and a short YouTube video that summarizes the procedure.

VIDEO: 1983 BMW R80ST Replace Wheel Bearings & Set Pre-Load

1983 BMW R80ST Replace Push Rod Tubes

I had the cylinders vapor blasted. In preparation, I removed the push rod tubes. After they were vapor blasted I install new stainless steel pushrod tubes I got from Euro MotoElectrics, who graciously has agreed to provide the parts for this charity rebuild project for free. I will auction this bike and proceeds will go to the Motorcycle Relief Project.

I have done this work before on my 1983 R100RS rebuild and will reference material from the documentation of that build as appropriate.

Here is what I started with before vapor blasting the cylinders and replacing the push rod tubes.

Original Cylinder And Push Rod Tubes

Original Cylinder And Push Rod Tubes

Here is a link to the documentation and a short YouTube video summarizing the procedure.

VIDEO: 1983 BMW R80ST Replace Push Rod Tubes

This is the final result.

New Stainless Steel Push Rod Tubes Installed In Vapor Blasted Cylinders

New Stainless Steel Push Rod Tubes Installed In Vapor Blasted Cylinders