New Engine Installation Tech Tips


Installing Your New Engine
The day has arrived and you are ready to order the new engine that you have been wanting. You should begin planning the installation when you order your engine. Here are several things to check during installation that are often overlooked. 

When ordering the new engine it is wise to order replacements for any questionable parts. If the battery cables, throttle cables, oil lines, primary chain, spark plugs, etc. are old and worn, order replacements when you order the engine. This will save you down time. 

Once you have removed your old engine it is time to prep the rest of the chassis. Replace any worn motor mounts in rubber mount chassis. Remove the oil tank and oil lines (if tank is removable from chassis) and flush thoroughly. If the tank is not removable flush it in place. This step is often overlooked and leftover debris is drawn into the new engine the first time it is fired, this debris can cause premature wear or damage. Also remove any paint or powder coat from the motor mounts. If the mount is not clean the paint will wear away over time causing the engine to be loose in the frame. 

Install the engine and check that the bottom motor mounts are sitting flat, if not shims may be needed between the engine and frame to fill the gaps. Check that the top motor mount is flush to the engine and the heads, if there are gaps between any of these shim them to fill the gap. Check the primary drive alignment during the installation and correct if needed. Use new locking nuts on the bottom motor mounts. 

Triple check the oil line routing to the new oil pump using the S&S instructions. Once oil line routing is verified prime the oil pump according to the instructions. Make sure the freshly cleaned oil tank has the proper amount of oil in it. Install the correct S&S oil filter for your application and engine. 

Use new spark plugs of the correct heat range and proper gap. You may need to flush your fuel tank if rusty or full of debris; installing a good quality inline fuel filter is advised as well. Lubricate the throttle cables, connect and adjust as needed. Once adjusted verify the throttle opens and closes completely and smoothly. These are just some of the many things to watch for when changing the engine. Attention to detail can save time and repair costs.
How Should I Break-In My New S&S Engine?
NOTE: S & S Engines require premium gasoline (octane 91 or higher) for best performance. Octane boosting gasoline additives may be necessary with marginal gasoline.

CAUTION: Low octane gasoline and hot weather can cause detonation and extensive engine damage. Never try to power through ignition knock ("ping," "rattle," etc.) by opening throttle.

CAUTION: If engine is run with foreign material in the oil tank, engine damage will occur. Engine damage caused by foreign material in the oil tank is not covered under the S&S warranty.Clean oil tank and oil cooler and flush or replace oil lines before installing engine in frame.

Engine Break-In Procedure
Note: S&S engines are designed for high performance and as such are not as tolerant of inadequate break-in as stock or lower performance engines. Correct breakin will assure longer engine life and will prevent unnecessary engine damage. Engine damage caused by improper break-in is not covered under the S&S warranty.

A. Initial start up. Run engine approximately one minute at 1250-1750 rpm. DO NOT crack throttle or subject to any loads during this period as head gaskets are susceptible to failure at this time. During this time, check to see that oil pressure is normal, that oil is returning the oil tank, and that no leaks exist.

B. Shut off engine and thoroughly check for any leaks or other problems. Let engine cool to the touch.

C. After engine has cooled, start up again and allow the motor to build some heat. Engine should be run no longer than three to four minutes. When the cylinders become warm/ hot to the touch (approximately 150°) shut the motor down and let it cool to room temp. Follow the same cautions as for the initial start-up, and continue to watch for problems.

D. Repeat this procedure 3 or 4 times. Each successive time it should take slightly longer to warm up and you can increase the temp slightly each time (+10°). You can be more liberal each time with the rpm, gently vary rpm continuously from idle up to 2500 rpm in the final cycle. Don't be too concerned with final carb settings at this time because idle speed and mixture cannot be correctly set until the motor reaches full operating temperature. The motor should not reach that temperature during these cycles. Do not allow engine temperature to become excessive. After the motor has cooled to room temperature for the final time you are ready to start the 1000 mile engine break-in process.

E. The first 50 miles are most critical for new rings and piston break-in. Engine damage is most likely to occur during this period. Keep heat down by not exceeding 2500 rpm. Avoid lugging the motor, riding in hot weather or in traffic. Vary the engine speed. Do not lug the engine. We recommend changing the oil at 50 miles.

F. The next 500 miles should be spent running engine no faster than 3500 rpm or 60 mph. Avoid continuous steady speeds, and do not lug the engine. Vary engine rpm. We recommend changing the oil again at 500 miles. 

CAUTION: Lugging or running engine prematurely at sustained high rpm may result in damage to pistons and other engine components. S&S voids it's guarantee if engine is not broken in properly.

G. For the balance of the first 1000 miles the motor can be run in a normal but conservative manner. You can be more liberal with the rpm range and motorcycle can be operated at normal highway speeds. Avoid overheating or putting any hard strain on the engine: no drag racing, dyno runs, excessive speed, trailer towing or sidecar operation.

H. After 1000 miles, verify carburetor jetting and adjustment. Change the engine oil. Motorcycle can now be operated normally.

I. Have Fun!
Break-In Your Engine on a Dyno
Dyno Break-In Procedure
  1. Follow the same procedure outlined above for initial start-up and heat cycling the engine.
  2. Run the bike for 25 miles on the dyno under varying speeds and loads while going up and down through the gears. Keep engine RPM below
    3,500 RPM but do not lug the engine. The dyno must be operated so the engine runs under a load roughly equal to the power needed to move
    the bike down the road, this would be about 12 hp at 55 mph. Keep engine head temperatures below 200 °F at the temp sensor or surface of
    the head. Stop and cool the engine if needed.
  3. Allow the engine to cool down to room temperature
  4. Run the bike for 25 more miles (50 miles total) under varying speeds, loads, gears as before. Make sure there is some load on the engine.
    Keep engine speed below 4,250 rpm but do not lug the engine. Limited short bursts of throttle can aid in ring seating. Keep engine head
    temperatures below 225 °F at the temp sensor or surface of the head.
  5. After the first 50 miles on the dyno, it is recommended the normal break-in schedule be followed under normal riding conditions on the street.
    See Step 5 above.

During the break-in period the ECM will automatically limit engine RPM in 2 stages during the first 20 hours of engine operation. During the first 2
hours of operation the engine rev limiter is 4250 RPM. From 2 hours to 20 hours of engine operation the rev limit is 5125 RPM. After 20 hours the rev
limit is set at the engines maximum RPM of 5600 RPM.

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