M A C H I N I N G & S E R V I C E S

Spec II's forte resides, among other things, in boosting your motorcycle's power through porting. We offer many stages of porting, and we can also perform various maintenance tasks to your crankshaft. Cylinder boring is also offered, as is a Big Bore kit. We can even clean your Power Valve assembly!

2-Stroke Porting - 4-Stroke Porting - Crank Work - 2-Stroke Cylinder Work - 4-Stroke Cylinder Work - Head Work - Other

PORTING STAGES (2-Stroke)- The following porting services are the result of extensive Racing & Development Programs. All porting stages start with aligning and balancing of the transfers. We have found this to be the only way to produce consistently high horsepower engines that also have wide, flexible powerbands. Each stage indicates an increase in the numer of ports wrked on. Also, for RD400, Stages II through IV include a spacer (and the machining it takes to make it work) and machining on the piston. It is important that we know the application the engine is to be used on.

Part # 150LRZ - Stage I Porting. Power increases in the mid- to upper power range.
Part # 225LRZ - Stage II Porting. Adds to power gained in Stage I. Broadens powerband making the machine easier to ride.
Part # 300LRZ - More power for you addicts out there.
Part # 400LRZ - Stage IV Porting. Primarily designed for racing. Achieves the ultimate in horsepower output.

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PORTING (4-Stroke)- All porting represents the results of many hours of testing and flow bench work. The testing represents both road racing and dragstrip participation.

4 Cylinder Head/8 Valves : Port & Polish
4 Cylinder Head/16 Valves : Port & Polish
Competition Valve Job : 8 Valves
Competition Valve Job : 16 Valves

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CRANK WORK - LABOR : Crank Lightening reduces the weight of the crankshaft 13%. Spec II machines special aluminum plates or bars (depending on the crank) to maintain crankcase compression at an optimum level. This machining results in greater acceleration at no expense to the powerband.

Crankshaft Rebuilding - 2-Stroke Twin
Crankshaft Rebuilding - 2-Stroke Triple
Crank Welding - Includes Truing After Welding
Crank Lightening - RD 400 '76-'78 Hardened Crank
Crank Lightening - RD350
Crank Stuffing Only

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CYLINDER WORK : (2-stroke)

Part # 10BRZ : Cylinder Boring, Per Cylinder. (Includes port chamfering.) Multiply X2 for price of complete top-end.
Part # 15BRZ - Big-Bore (372cc). For RZ350 - Call for further details.
RD350 Big-Bore - Call or Write for more details.
Part # 10PRZ - Remove, clean & assemble Power Valve. (Includes both cylinders.)
RD400 Big-Bore (Call or write for more details)
Barrel Surfacing

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CYLINDER WORK : (4-stroke)

Next Overbore (Clean-Up) - Each Hole
Large Overbores (Per .040" Cut)
All 4 Cylinders -
Bore Blocks & Surface for Resleeving
XS750 to 900/912 (Sleeves Installed & Surfaced)
Barrel Surfacing

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2-Stroke - Each
CC chambers to match exhaust port height

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Assemble Heads - Seals Extra
Carbon Removal
Cam Cut - Machining of the head to clear big cams


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Spec II

12866 Foothill Blvd
Sylmar, CA 91342
Tel. : (818) 837-1313
Fax : (818) 837-1224

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