After the first engine start, I began the break-in and shake down for this 1983 R80ST. My goal is to break-in the bike in about 600 miles, and to be sure everything is working correctly. My experience after a major rebuild like this one is that there are always some issues and the need for some tweaks and fiddling to get everything working perfectly. So far I have put almost 900 miles on the bike.
Date For Selling The Bike And Donating Proceeds To MRP
Ted Moyer, Executive Director of the BMW Motorcycle Owners Of America (MOA), contacted me awhile back to talk about my project. The MOA Foundation supports the Motorcycle Relief Project and he wanted to know if I would be interested in having the MOA Foundation run a raffle to sell the bike and send all the proceeds to the MRP. I told him that sounded like a good idea. Ted took the idea to the MOA Foundation board of directors and they approved it.
So the MOA Foundation will hold the raffle in December 2023 through January 2024. MOA plans to initiate the raffle at the annual MRP December dinner fund raising event. You can visit the BMW MOA Foundation website to buy raffle tickets in December-January. Currently the MOA Foundation is holding another raffle that ends on October 31.
This is a summary video of the break-in riding and some of the issues I fixed along the almost 900 miles I rode the bike.
VIDEO: 1983 BMW R80ST Break-In Riding Log And BMW MOA Raffle Info
Below is a list of all the things I addressed during the break-in rides at various mileages. I put almost 900 miles on the 1983 R80ST breaking it in.
First 10 Mile Ride
I wasn’t able to get the bike into first gear, but I rode it for the 10 mile break-in ride anyway holding the RPM at 3,000 and then increasing it to 4,000 and letting it fall back to 3,000 with an occasional blip up to 4,500 RPM.
I found the foot shifter linkage was interfering with the left exhaust header. So I adjusted the linkage to pull the foot shift lever a bit higher and that did the trick as then the transmission went into first gear.
I changed the engine oil and the transmission, drive shaft and rear drive gear lube. The magnet on the transmission drain plug showed some bits of steel from the new gears, but that’s normal and is one reason I drain the oil and gear lube after 10 miles to clear all that out and also to remove the engine assembly lube I used.
I did another 10 mile ride and balanced the carburetors with my Grok balancer. The idle was about right but I had to adjust the throttle cable lengths to get them balanced off-idle.
I only put about a gallon and a half of gas in the tank for the first two 10 mile rides, So I rode a half-mile to a local gas station to fill the tank. The tank starting leaking gas along the left side of the tank. It looked like the leak was starting about where the bracket is in the front of the tank that fits on the rubber bumper on the steering head.
I rode the bike the half-mile home and drained the tank. I could see a crack in the weld around the front tank bracket that fits over the rubber bumper on the frame tube.
I used a Dremel grinding bit and cleaned off the paint around the crack. Then I used JB Weld to fill in the crack and also put some around the bracket so it would be secure.
I put a bit of gas in the tank, tilted it so the gas would be at the front of the tank around the front bumper bracket and let it sit that way for an hour. There was no leak. So I filled the tank with gas, and it was good to go.
As I rounded a corner a bit deeper than I had before, I heard a scaping sound. I stopped and saw that the center stand did not retract all the way. It turns out the exhaust collector was interfering with the left leg of the center stand preventing it from going all the way up.
I removed the rear tire and loosened all the exhaust system clamps and the header pipe nuts. I used a rubber mallet on the rear of the collector and knocked it farther up the exhaust header pipes. Now the center stand leg clears the rear of the exhaust collector.
The plugs are dark indicating the carburetors are running a bit rich.
The left mirror got loose on the stalk. So I tightened the nut behind it as it had gotten loose.
There is also a bit of front end vibration around 35-45 MPH. I took the wheels to Woody’s Wheel Works and had them check them for being true as these were the first wheels I laced. They said they only had to make some minor adjustments.
I rebalanced the wheels. They were a bit out of balance. Now when I spin them to any position on my wheel balancing stand, they stay right where I put them without turning.
When I installed the front axle, three of the wheel bearing shims came out. So I removed the front bearing dust cover, the inner bearing and wedding band on the right side and replaced the shims, but this time, I put them under the wedding band.
See the 650 Miles section below for what I did to finally correct the front end vibration problem.
I changed the main jets from 150 to 135 to reduce how rich the carburetors are. Then I rebalanced the carburetors. I was getting 30 MPG with the 150 jets, which is very low. After the main jet change, mileage improved to about 40 MPG.
I changed the engine oil. I also changed the transmission and rear drive gear lube as both were rebuilt. There was a fair amount of metal flakes on the transmission drain plug and a small amount on the rear drive drain plug indicating the new parts are wearing in. I like to replace the gear lube after a transmission rebuild so I get as much metal debris out of the transmission as I can and keep the gear lube clean during break-in.
I checked the valves. I had set them to 0.006 in for the inlet and 0.008 in for the exhaust. I found the following clearances.
Intake: 0.002 0.002
Exhaust: 0.006 0.006
So the intake had closed up a lot.
I retorqued the heads to 25 Ft-Lbs and found them a bit loose. Then I reset the valves to 0.006 in for intake and 0.008 in for exhaust. Since the heads were rebuilt, it’s common for valve clearances to take some time to become stable. That’s why I check them at about 200 miles, 400 miles and 600 miles, so I can determine when the clearances are getting stable.
The right side headlight bolt and chrome flat washer are missing. So I got new ones and will use some blue Loctite on the bolts so they don’t come loose again.
I checked the valves again. I found them a little bit tight, so I reset them to 0.006 in for the intake and 0.008 in for the exhaust. Before setting them I retorqued the heads and they were just a tiny bit loose this time.
The plugs still have a fair amount of black on them, so the carburetors are still running a bit too rich. I moved the jet needles down from position 3 to position 2. I’ll see how that affects the spark plugs. I ran the bike for about 10 miles and then rebalanced the carburetors. I’ll ride a the bike a for some more miles and then check the plugs to see if they are a bit leaner..
The right side cover isn’t staying tight on the pins. The front bracket of the cover keeps coming off the rubber bushing on the forward facing pin. So I pulled it off and added some more Plast-aid to the front bracket and made it a complete circle around the rubber bushing as was the case on the left side cover. That fixed the problem and the right side is tight on the pins now.
BMW recognizes 600 miles as the end of the break-in period. So, I’ve achieved break-in mileage. 🙂
After changing the carburetor main jets to 135 and dropping the jet needle one notch lower from position 3 to position 2. After that adjustment I’m getting 45 MPG which is good for a naked bike. Keep in mind I live in metropolitan Denver, CO which is at a mile high and I often ride in the mountains at 8,000-9,500 feet, so dropping the jet needle makes sense to keep the carburetors from running too rich at this altitude.
I changed the engine oil and filter, the gear lube in the transmission, driveshaft and rear drive. The transmission magnetic drain plug showed only a small amount of metal filings. The rear drive drain plug was completely clean. So that’s good news. I cut open the oil filter and looked at it. I only saw small specs of metal, so that too is good.
I checked the valves by first checking the cylinder stud nut torque. All the six nuts on each side were holding at 25 Ft-Lbs, so that’s good. The intake and exhaust valves had tightened about 0.001 inch, so they are getting stable. I reset the valve clearance to the stock settings of 0.004 inch for the inlet and 0.006 inch for the exhaust from the break-in clearances of 0.006 inch intake and 0.008 inch exhaust.
I checked the timing and found it was a bit advanced, so I adjusted the timing.
I drained and refilled the front fork oil with 190 cc per fork leg.
I found the steering head bearings were a bit loose so I tightened the preload nut and then torqued the top nut to 86 Ft-Lbs.
I checked the engine mounting stud torque and found they were a bit loose so I reset them to 55 Ft-Lbs.
I checked the swing arm pivot bolt torque by removing the lock nuts. They were unchanged. So I torqued the lock nuts back at 77 Ft-Lbs.
So, at this point I can run the RPM up past 4,000 and I will take it up to 5,000 for another 100 miles or so.
Now that the paint has been over a month since it was applied, I will wash the bike and wax the painted parts.
I’ll likely put some more miles on the bike before selling it.
I had been experiencing some suspension harshness around 35-45 MPH as noted in the 130 Miles section.
Despite the changes, the harshness at lower speeds was still evident. So I took the bike to Matt Iles at Iles Motorsports so he could ride it and give me his assessment. He said he was pretty sure there was a lot of stiction in the front forks. I had trued the fork tubes, but maybe they weren’t true anymore. So I took the fork sliders off and checked the fork tubes and they were still true. Then I carefully moved the sliders on the tubes and it was clear there was a lot of stiction on the lower end of one of the fork tubes. I looked at my documentation of rebuilding the forks and noted I had found some kinks in the lower section of one of the fork tubes which I didn’t think was serious enough to replace the fork tubes. Obviously I was mistaken.
So I ordered new fork tubes from MAX BMW and also ordered a new fork brace (aka, bow) that the front fender mounts to as the one a friend gave me was a bit deformed and I had to shim it when I installed it.
I installed the new fork tubes and trued them again. After I installed the forks and new fork brace, I took a test ride and the ride was much smoother now, so this was worth it.
Some Views From My Break-In Riding
Here some pictures of the countryside I rode through on my break-in rides.