Now that I the gas tank installed, I’m ready for the first engine start. But, before I try to start the engine, I perform a number of checks on the bike to be sure I haven’t forgotten anything. After the first engine start, I ride the bike for 10 miles to start the break-in and to evaluate how everything is working.
This is a summary video of the preparations for and the first engine start.
VIDEO: 1983 BMW R80ST First Engine Start
First Engine Start Checklist
I put together a checklist for the first engine start and first 10 mile ride start so I don’t forget anything. I check off each item as I complete it.
√Install And Gap Spark Plugs
|√||Verify Engine Oil Level|
|√||Verify Transmission Oil Level|
|√||Verify Rear Drive Oil Level|
|√||Verify Swing Arm Oil Level|
|√||Verify Fill & Drain Bolts Tight|
|√||Oil Pressure & Flow Check|
|√||Remove Spark Plugs & Ground|
|√||Crank for 5 seconds and then rest|
|√||Verify Oil Pressure Light Goes Out|
|√||Verify Oil Flows From Top Of Rocker Blocks|
|√||Install Valve Covers|
|√||Statically Set Ignition Timing|
|√||1st Engine Start Sequence|
|√||Fuel On Reserve|
|√||Check Fuel Level In Float Bowls (28 mm)|
|√||15 Seconds @ 3000 RPM|
|√||45 Seconds @ 3500 With Blibs To 4000 RPM|
|√||Ride For 10 Miles (15-25 Minutes) Vary RPM 3000-4000 RPM|
|√||Back Off Throttle Then Accelerate Every Minute or So To 4,500 RPM|
I verify that the engine has oil and the transmission, drive shaft and rear drive have gear lube in them. I remove the transmission fill plug and verify the fluid level. Then I remove the drive shaft and rear drive fill plugs and use a pencil to confirm there is gear lube in them.
Check Oil System Is Working
Before the first engine start, I want to get oil through the entire oil system. I remove the spark plugs and ground them on the engine block so the starter motor doesn’t have to work hard. I insert the plugs into the gap in the center of the heads so when the engine is spinning the plugs are grounded. If they aren’t the electronic ignition system will be damaged. I remove the valve covers and put an oil pan under the heads to catch the oil that should flow out of the rocker blocks.
I spin the engine for 5 seconds and let it rest so the starter motor doesn’t overheat. I repeat this until the oil light goes out. Then I verify that oil is flowing out of the rocker arm top blocks with the split in it. The top rocker blocks are at the end of the oil path so that ensures oil is flowing through out the oil system and it verifies that when I installed the cylinders and applied gasket sealant, I didn’t obstruct the oil passages that feed the top cylinder stud passages leading to the top rocker blocks.
Check Ignition System Is Working
With both spark plugs grounded, I pull one up and lay it against the head. Then I hit the starter to verify I can see a spark. I repeat this with the other plug. Then I ground both spark plugs and use my timing light to verify the ignition timing is set correctly with the line under the “S” across from the groove in the timing plug hole in the engine block.
Check Carburetor Float Level
I put about 1-1/2 gallons of gas in the tank. I turn the petcock to reserve and let the gas flow. I verify that the carburetors are not overflowing. Then I turn the petcock off and carefully remove the float bowls to verify they are filling with gas. Next, I put the float bowl back on one carburetor. I push the float all the way up and turn the petcock to reserve. I gently lower the float and check to see when gas just starts flowing. The top of the float should be even with the seam of the float bowl with no gas flow and dropping it just a bit should allow some gas to trickle out. I repeat this procedure with the other carburetor. Both floats are adjusted correctly.
First Engine Start
Now that I have verified the bike is ready for the first engine start, I’m ready to go. The procedure is to get the engine running on minimal chock (I had to use full choke to get it started then quickly reduced it) and rev it to 3,000 RPM for 15 seconds. Then I increase the RPM to 3500 with occasional blips to 4,000 RPM and reduce the RPM to 3,000 again. I continue this cycle for 45 seconds.
This procedure helps push the piston rings tight against the cylinder walls so they will wear into the cylinder and ensure a tight oil seal.
The bike started and ran with no explosions, or smoke leaking out of the wiring 🙂
10 Mile Ride
After the first engine start, I put the seat on and I take it for a 10 mile ride to start the initial break-in and to verify the brakes work, transmission works, suspension works and electrical system works.
I’m waiting to mount the side covers and muffler heat shield until after I get the gas tank and side panels pinstriped.
The procedure for the 10 mile ride is to try and hold the RPM at 3,000 minimum and the increase to 4,000 and let it come back down to 3,000. I occasionally increase the RPM to 4,500 and let back down to 3,000 RPM. I try to follow this procedure in all five gears to ensure the transmission is working.
Check For Leaks And Drain All Fluids
After the 10 mile ride, I checked all the drain plugs and the front brake lines for any leaks. Everything was dry. Then I drained the engine, transmission, drive shaft and rear drive to remove debris, engine assembly lube and any metal fillings that were generated. There were some small bits on steel shavings on the transmission drain plug which is typical when you replace any gears in the transmission, as I had to do. That’s why I like to drain all the fluids after the 10 mile ride.
The good news is the 1st engine start and 10 mile ride went very well. 🙂
Things I Had To Correct
- On the 10 mile ride I couldn’t get the transmission to shift into 1st gear. I found out the bottom of the foot shifter was touching the left exhaust header. I adjusted the foot shifter linkage to pull the shift lever higher.
- After I parked the bike overnight I found the petcock was leaking so I tightened it a bit more on the gas tank fitting. The leak stopped.
- I forgot to install the petcock screen so I removed the petcock and installed the screen.