Click to enlarge

                 120CC SLEEPER KIT

*

 "SLEEPER"  MEANS AFTER THIS KIT IS INSTALLED NOBODY CAN TELL YOUR ENGINE IS NOT JUST STOCK

98% OF YOU WILL HAVE TO FIND A MACHINE SHOP TO INSTALL THIS KIT !!

IF YOUR OLD PARTS ARE GOOD YET (IE ROD/BALL BEARINGS/CHAIN SPROCKET) ALL YOU NEED TO BUY IS THE CORE KIT AND YOU WILL HAVE ALL THE PARTS TO MAKE YOUR 89CC INTO A 120CC ENGINE

YOUR CYLINDER WILL NEED TO BE BORED TO MATCH THIS PISTON, WITH .001" TO .002" CLEARANCE

YOUR CRANK WILL NEED TO BE PRESSED APART THEN BACK TOGETHER AND TRUED UP

==============================================

Hey Jack,

I just wanted to give you a status update. I have about 250 miles on the 120cc kit, it's great fun.

If someone is in Denver or similar elevation and they want to use the stock carb with the altitude adjuster, the best settings are:

35 pilot jet 72 main jet needle on middle shim 1.5 turns out on the air screw

I can get over 50mph on the flats and I'm 260lbs. Larger jets run too rich at my altitude and the engine's hot enough I wouldn't go leaner. I understand the 22mm carb will breathe easier but at my weight 50mph is spooky enough and I have other bikes for pure speed. The CT geometry seems happiest at 40mph and your kit's given it outstanding grunt for such a little bike.

Thanks again for creating such a cool kit for the bike!

- Eric N



"DIY" NEW TYPE OHC90 HEAD/CYL 120cc "SLEEPER" STROKER CRANK CORE KIT READ FITMENT CAREFULLY (273L/253K/335T/296N)
"DIY" OLD TYPE OHC90 HEAD/CYL 120cc "SLEEPER" STROKER CRANK CORE KIT READ FITMENT CAREFULLY (273L/253K/313i/296N)
CONNECTING ROD KIT CT90 ATC90 S90 ST90 CM91 SL90 CL90 1/17T (329Z)
(CT90_ATC90_ALL)  (CT110_ATC110_ALL)  LARGE_CRANK BEARING (SOLD_EACH) 1/14M BG27
*CRANK_TIMING_SPROCKET (15_TOOTH_19.20MM_ID) CT90_CM91_S90 CL90_SL90_ST90 1/14M (42G)
*15_TOOTH CRANK_TIMING_SPROCKET (ATC90_ATC110) (CT110_ALL_YR) (ATC125M_84-85) (21.20MM_ID) 7/16A (326E)
"DIY" NEW TYPE OHC90 HEAD/CYL 120cc "SLEEPER" STROKER CRANK CORE KIT READ FITMENT CAREFULLY (273L/253K/335T/296N)

Regular price: $149.95
Sale price: $129.99
"DIY" OLD TYPE OHC90 HEAD/CYL 120cc "SLEEPER" STROKER CRANK CORE KIT READ FITMENT CAREFULLY (273L/253K/313i/296N)

Regular price: $149.95
Sale price: $129.99
CONNECTING ROD KIT CT90 ATC90 S90 ST90 CM91 SL90 CL90 1/17T (329Z)

$49.95
(CT90_ATC90_ALL) (CT110_ATC110_ALL) LARGE_CRANK BEARING (SOLD_EACH) 1/14M BG27

$12.98
*CRANK_TIMING_SPROCKET (15_TOOTH_19.20MM_ID) CT90_CM91_S90 CL90_SL90_ST90 1/14M (42G)

$29.50
*15_TOOTH CRANK_TIMING_SPROCKET (ATC90_ATC110) (CT110_ALL_YR) (ATC125M_84-85) (21.20MM_ID) 7/16A (326E)

$27.99
CRANK PIN SET OHC90 TO 120CC KIT 273L/296N/296N
PISTON KIT FOR OHC 90CC'S 120CC STROKER CRANK KIT 253K
NEW TYPE HEAD/CYLINDER OHV 90CC BIG BORE HEAD GASKET 1/18L (335T)
BIG_BORE_HEADGASKET OLD TYPE 90CC HEAD GASKET (NO_KNOTCHES) <p>COPPER HEAD GASKET 54.60MM ID 64.60MM OD .032" THICK (313i)
**OEM CRANKSHAFT BEARING CT90 ATC90 CL/S/SL/CM91 ATC110 CT110 ALL (SOLD_EACH) 1/18M (334C)
CT90_ATC90 ST90_CL90 SL90_S90 CS90_CM91 (ATC110'S_READ)  PERFORMANCE CAMSHAFT 1/17P (90/PER/CAM)
CRANK PIN SET OHC90 TO 120CC KIT 273L/296N/296N

$69.95
PISTON KIT FOR OHC 90CC'S 120CC STROKER CRANK KIT 253K

$79.95
NEW TYPE HEAD/CYLINDER OHV 90CC BIG BORE HEAD GASKET 1/18L (335T)

$4.99
BIG_BORE_HEADGASKET OLD TYPE 90CC HEAD GASKET (NO_KNOTCHES)

COPPER HEAD GASKET 54.60MM ID 64.60MM OD .032" THICK (313i)

$4.95
**OEM CRANKSHAFT BEARING CT90 ATC90 CL/S/SL/CM91 ATC110 CT110 ALL (SOLD_EACH) 1/18M (334C)

$25.99
CT90_ATC90 ST90_CL90 SL90_S90 CS90_CM91 (ATC110'S_READ) PERFORMANCE CAMSHAFT 1/17P (90/PER/CAM)

$37.95
Click to enlarge
ALIGN CRANK SPROCKET UP THIS WAY