S&S Cycle Oil Pump for T-Series Engines and Harley-Davidson Twin Cam 88 Engines, Including Standard and Easy Start Camshafts User Manual
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Notes:
If using stock heads, you will need to verify that the valve springs are capable of handling the lift of the camshafts.
•
Piston to valve clearance will need to be confirmed when using a cam with over 0.510" of lift. Clearance should be at least 0.060" intake and .080" exhaust.
•
Valve to valve clearance will need to be confirmed when using a cam over 0.510" lift. Clearance should be a minimum of 0.060".
•
All reference to Harley-Davidson® part numbers is for identification purposes only. We in no way are implying that any of S&S Cycle's products are original
•
equipment parts or that they are equivalent to the corresponding Harley-Davidson part numbers.
OVERVIEW OF EASY START CAMSHAFTS (IF EQUIPPED):
S&S has developed a unique product to assist starting with the compression release cam. The premise is simple: at cranking speeds a spring loaded
decompression lever holds the exhaust valve open slightly. Once the engine fires and exceeds 750 rpm, centrifugal force takes over and sends the
lever to a retracted position, allowing the engine to run normally.
Important Notes Regarding Easy Start Camshafts:
NOTE: Stock EFI engines require a minimum of 80 PSI cranking compression, checked with the throttle open, for the ECU to fire the spark plugs.
The easy start cams were designed to work with the compression ratio and displacement combinations that the cam was intended for. Due to a near infinite
number of engine combinations, manufacturing tolerances, or if the cam is used outside our recommended compression ratios, occasionally an engine
may not build the required compression to start the bike. For these cases we offer cams that do not release as much compression. Please call our technical
department at 1-608-627-8324
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Valve to Piston Clearance Chart
Harley-Davidson® Pistons*
Head
Style
Cam
509
510
570e
585e
625e
640e
675e
Stock
OK
OK
OK
OK
1
1
S&S 79cc
OK
OK
OK
1
1
1
S&S 89cc
2
2
2
2
2
2
Chart 2
*
Using unmodified heads with .045" head gaskets.
OK=
No Clearancing needed.
1=
Valve to piston clearances must be checked.
2=
Valve pockets in pistons must be modified.
EASY START CAMS