1983 R80ST Rebuild For Charity Project Journal

[brook.reams]

Since this project bike was not running when I picked it up and had been sitting outside for awhile, I don't know what components of the electrical system work. So I remove the starter motor and test it.


What The 1983 R80ST Looked Like When I Found It

Here is the link to the documentation on how I do this work and a short YouTube summary of the process.

• 12 BMW R80ST Remove And Test Starter Motor

VIDEO: 1983 BMW R80ST Remove And Test Starter Motor

The good news is the starter motor was in good condition and worked correctly. :-) I cleaned up the starter motor and the top engine compartment it sits in.


Starter Motor Nose Refinished


Front Starter Motor Bracket Refinished


Top Engine Housing Is Clean

[brook.reams]

I've removed the airbox, transmission, clutch and flywheel to gain access to the oil pump. You can see how I did that work here.

• 13 BMW 1983 R80ST Remove Air Box & Pulse Air System


• 23 BMW 1983 R80ST Remove Transmission


• 21 BMW 1983 R80ST Remove Clutch


• 11 BMW 1983 R80ST Remove Flywheel

I've published documents on removing, inspecting and installing the oil pump on other projects. Here are links to those documents.

• 11 BMW 1977 R100RS Replace Rear Main Seal & Oil Pump Cover O-Ring


• 11 BMW 1983 R100RS Remove & Inspect Oil Pump


• 11 BMW 1983 R100RS Install Rear Main Seal, Oil Pump Cover & O-ring

Here is the link to how I do the work on the 1983 R80ST.

• 11 BMW 1983 R80ST Remove, Inspect, Install Oil Pump

And, here is a short video that summarizes how I do this work.



VIDEO: 1983 BMW R80ST Remove And Inspect Oil Pump


Oil Pump Cover Removed


Oil Pump Rotors Marked With "F" For Front Face


Oil Pump Measurements - They Are All Good

[brook.reams]

I've removed the airbox, transmission, clutch and flywheel to gain access to the rear main seal so I can replace it. You can see how I did that work here.

• 13 BMW 1983 R80ST Remove Air Box & Pulse Air System


• 23 BMW 1983 R80ST Remove Transmission


• 21 BMW 1983 R80ST Remove Clutch


• 11 BMW 1983 R80ST Remove Flywheel

I've published documents on replacing the rear main seal on other projects. Here are links to those documents.

• 11 BMW 1983 R100RS Remove Flywheel & Rear Main Seal


• 11 BMW 1983 R100RS Install Rear Main Seal, Oil Pump Cover & O-ring


• 11 BMW 1977 R100RS Replace Rear Main Seal & Oil Pump Cover O-Ring


• 11 BMW 1975 R75/6 Replace Crankshaft Rear Oil Seal, Oil Pump Cover & O-ring


• 11 BMW 1973 R75/5 Remove & Install Flywheel, Replace Rear Main Seal, Oil Pump Cover & Cover O-Ring

Since the 1983 R80ST engine is similar in many ways to the 1983 R100RS, I link to the 1983 R100RS documents as appropriate in this document.

• 11 BMW 1983 R80ST Replace Rear Main Seal

Here is a short YouTube video showing how I do this work.



VIDEO: 1983 BMW R80ST Replace Rear Main Seal

I had a real problem removing the seal on this bike using my usual approach with the Cycle Works rear main seal tool, and had to resort to using "a bigger hammer". I used a hook seal puller to pry the old rear main seal out of the bore. Since the bike has been sitting for 25-30 years, the seal was really stuck in the bore.


Cycle Works Rear Main Seal Tool


Using Hook Seal Puller To Remove Rear Main Seal


Using Flashlight To Verify Seal Is Flush With Case

[brook.reams]

I've removed the airbox, transmission and clutch to gain access to the flywheel. You can see how I did that work here.

• 13 BMW 1983 R80ST Remove Air Box & Pulse Air System


• 23 BMW 1983 R80ST Remove Transmission


• 21 BMW 1983 R80ST Remove Clutch

I also show how to remove the flywheel here.

• 11 BMW 1983 R80ST Remove Flywheel

I've published documents on removing and installing the flywheel on other projects. You can see those documents here.

• 11 BMW 1973 R75/5 Remove & Install Flywheel, Replace Rear Main Seal, Oil Pump Cover & Cover O-Ring


• 11 BMW 1977 R100RS Replace Rear Main Seal & Oil Pump Cover O-Ring
  
  
  
  • Remove the Flywheel
  
  
  • Install Flywheel
  
  
  
  
• 11 BMW 1983 R100RS Remove Flywheel & Rear Main Seal


• 11 BMW 1983 R100RS Install The Flywheel

Since the 1983 R80ST engine is similar in many ways to the 1983 R100RS, I will link to the 1983 R100RS documents as appropriate in this document.

• 11 BMW 1983 R80ST Install Flywheel

Here is a short YouTube video showing how I do this work.



VIDEO: 1983 BMW R80ST Install Flywheel

Here is how things look now.


Flywheel Installed

[brownie0486]

Very impressive sir, thanks for all the sharing and knowledge you bring to the group

[brook.reams]

Very impressive sir, thanks for all the sharing and knowledge you bring to the group

You're welcome brownie0486.

[brook.reams]

Well, all the work on the rear of the engine is finished as I have completed installing a new clutch provided for free from Euro MotoElectrics who offered to provide free parts for this charity rebuild project to benefit the Motorcycle Relief Project.

Here is the link to the document about how I did this work.

• 21 BMW 1983 R80ST Install Clutch

I also shot a short video summarizing the work.



VIDEO: 1983 BMW R80ST Install Clutch

Here are some before and after pictures of the clutch. This one should be good for the next 100,000 miles.


Original R80ST Clutch Looks Very Bedraggled


Original Clutch Condition


New EME Supplied Clutch Pack Assembled For Installation On Face Of Flywheel


New Clutch Installed

[brook.reams]

This "project" bike has been sitting for over 25 years. So, for reliability, I'm going to replace the charging system which consists of the alternator, diode board and all associated wiring. I may try to rebuild the electronic ignition sensor, aka, the "bean can" that uses a Hall effect sensor to trigger the ignition. This document covers how I remove the components.

Also, I plan to replace the timing chain, crankshaft timing sprocket and the nose bearing which are behind the inner timing cover that the charging system and electronic ignition sensor are mounted to, so I have to remove all these components before I can remove the inner timing cover.

The original alternator looks a bit bedraggled.


Original Alternator Looks Bedraggled

I've replaced charging systems on other projects. Here are links to those documents.

• 12 BMW 1977 R100RS Replace Engine Electrical Components


• 12 BMW 1983 R100RS Remove Diode Board, Alternator & Electronic Ignition Sensor

Here is what the inner timing cover looks like after all the engine electrical components are removed.


Inner Timing Cover After Engine Electrical Components Removed

Here is a link to the document showing how I do this work, and a short YouTube video summarizing the work.

• 12 BMW 1983 R80ST Remove Alternator, Diode Board & Electronic Ignition Sensor

VIDEO: 1983 BMW R80ST Remove Alternator, Diode Board & Electronic Ignition Sensor

[brook.reams]

This "project" bike has over 63,000 miles on it. It's not uncommon for the timing chain and crankshaft sprocket to wear enough at that mileage to affect valve timing. Too much slack causes uneven timing of the valves. If valve timing varies, then ignition timing will not be optimal. In situations with a lot of wear, the chain can be heard slapping inside the motor. As I've never heard this bike run, I do not know if the timing chain is that loose, but that much slop in the timing chain is more common at 100,000+ miles on the chain.

I repainted the inner timing cover and you can read about that work here:

• 51 BMW 1983 R80ST Repair, Refinish & Paint
  
  
  
  • Paint Inner Timing Cover
  
  

Here is a link to the document showing how I do this work and some videos summarizing the work. Since I can only embed one video per posting, the other videos are included as links.

• 11 BMW 1983 R80ST Replace Timing Chain, Crankshaft Sprocket & Nose Bearing




VIDEO: 1983 BMW R80ST Remove Timing Chain, Crankshaft Sprocket & Nose Bearing


• VIDEO: 1983 BMW R80ST Install Crankshaft Sprocket And Nose Bearing
• VIDEO: 1983 BMW R80ST Install Timing Chain
• VIDEO: 1983 BMW R80ST Install Inner Timing Cover

[brook.reams]

Since this bike sat for more than 25 years, I replaced the the oil pan and oil pump suction gaskets. The oil pump suction gasket was brittle so it was time to replace it. None of the oil pan bolt threads were stripped, so that was a good thing. I also had the oil pan, that was painted orange by a previous owner, vapor blasted by the Colorado Vapor Blasting division of Vintage Twins, a local independent shop in my hometown of Arvada, CO. When I told them I was going to auction this bike and donate all the proceeds to the Motorcycle Relief Project, they generously provided me a nice discount on the work. :-)

Here is a before and after picture of the oil pan.


The Original Orange Oil Pan


All Done With Vapor Blasted Oil Pan


All Done With Vapor Blasted Oil Pan

You can read about how I do this work and see a short summary video here.

11 BMW 1983 R80ST Replace Oil Pan & Oil Pump Suction Flange Gaskets

VIDEO: 1983 BMW R80ST Replace Oil Pan and Oil Pump Suction Flange Gasket

[brook.reams]

Since this bike sat for more than 25 years and I found water in the oil pan, I replaced the connecting rod bearings. The bearings were in good condition and the crankshaft journals were not rusted and were well within specifications, so that was a relief. I replaced the bearing shells anyway rather than reuse the original ones that had 64,000+ miles on them.

You can read about how I do this work and see a short summary video here.

• 11 BMW 1983 R80ST Replace Connecting Rod Crankshaft Bearings

VIDEO: 1983 BMW R80ST Replace Connecting Rod Crankshaft Bearings

[brook.reams]

I replaced these components with new ones supplied my Euro MotoElectrics at no cost to me in support of my goal to auction this bike and donate all the proceeds to the Motorcycle Relief Project. EME has been very kind and generous to me on this project.
I installed their new Type 1 charging system kit, the EDL-1 107, which has all the parts to replace the stock 240 watt charging system including a new front crankshaft seal.

I also installed their remanufactured electronic ignition sensor, aka, the "Bean Can", and a new ignition system sub-harness.

You can read about how I did the work and see a YouTube video.

• 12 BMW 1983 R80ST Install Alternator, Diode Board & Electronic Ignition Senso

VIDEO: 1983 BMW R80ST Install Alternator, Diode Board & Electronic Ignition Sensor

This is what I started with.


Original Engine Electrical Components Under The Front Engine Cover


Original Diode Board


Original Alternator


Original Bean Can

And this is the final result.


All Done

[brook.reams]

This bike has the Nikasil plated aluminum cylinders. Nikasil is a nickel silicon carbide material that is extremely hard and wears very little and can be platted onto aluminum. That said, I want to measure the cylinders to determine if they are in good condition since the bike sat for about 25 years and had 64,000 miles on it.


Insert Bore Gauge Into Cylinder & Align With Top Measurement Circle

I previously measured the cylinders on my 1973 R75/5 and you can see that procedure here.

• 11 BMW 1973 R75/5 Measure Cylinders and Install Pistons & New Rings

On this bike, I measure the bore, ovality and taper using a bore gauge to see if these cylinders are still serviceable. I found Both cylinders are in good condition.


Bore Gauge Kit

After measuring the cylinders I remove the glaze on the cylinder walls using a ball hone. I use the Brush Research Flex-Hone® with 240 grit aluminum-oxide balls that they recommend for Nikasil cylinders. I use a 3-1/2 inch hone and my portable electric drill that has a low speed range of 600 RPM which is within the recommended 500-800 RPM Brush Research recommends.


Brush Research Flex-Hone Ball Hone & Honing Oil {I Bought WAYYYYY Too Much :-) }


After Honing-Good 45 Degree Cross-Hatch]

Here is a link to the document showing all the details of how I do this work and a link to a YouTube video.

• 11 BMW 1983 R80ST Cylinder Measurements & Honing

VIDEO: 1983 BMW R80ST Cylinder Measurements & Honing

[mikegalbicka]

Great job documenting this for others. Learning a lot as you step through this project. Keep up the good work and thanks for your efforts.

[brook.reams]

I had the swing arm powder coated, so I removed the drive shaft before taking it to the powder coater.

The 1983 R80ST swing arm is designed for a monoshock rear suspension, but the driveshaft is the same as the one used in the dual shock 1983 R100RS. I previously removed and installed the driveshaft in a 1983 R100RS and documented the work.


1983 R100RS Dual Shock Swing Arm Design


1983 R80ST Powder Coated Monoshock Swing Arm Design

This is a link to the documentation and a YouTube video showing how I remove and install the drive shaft.

• 33 BMW 1983 R80ST Remove & Install Drive Shaft

VIDEO: 1983 BMW R80ST Remove & Install Driveshaft