S&S Cycle 100″ Sidewinder Big Bore Kit For Harley Twin Cam 1999-2006
Maximize Displacement: The S&S Cycle 100″ Sidewinder Big Bore Kit for Harley Twin Cam (1999-2006)
For the Harley-Davidson rider who owns a 1999 through 2006 Twin Cam Big Twin (excluding 2006 Dyna models) and demands the ultimate in street performance, the S&S Cycle 100″ Sidewinder Big Bore Kit stands as the definitive upgrade. This kit is far more than just a bolt-on performance enhancer; it’s a complete conversion that takes the stock 88 cubic inch (1450cc) engine to a monstrous 100 cubic inches (1638cc). The increase in displacement, combined with the superior S&S components, delivers a massive surge in torque and horsepower, fundamentally transforming the bike’s riding dynamics.
Core Engineering and Component Quality
The S&S Sidewinder line represents the pinnacle of their performance parts, and the 100″ kit is a testament to their commitment to quality and power.
Sidewinder Cylinders and Pistons
Unlike the smaller 98″ kits which can often reuse stock heads, the 100″ Sidewinder requires a comprehensive approach. The kit features new large-bore cylinders that necessitate a specialized design to achieve the 100-inch displacement.
Piston Design: The kit utilizes high-strength, forged pistons designed for longevity and superior thermal management under extreme conditions. Forged pistons can handle the higher heat and pressure associated with the increased compression ratio (typically around 10.3:1 to 10.5:1, depending on the heads used), ensuring reliable performance.
Cylinder Construction: The cylinders are crafted from durable materials and often finished in a factory-matching aesthetic, such as Wrinkle Black or a natural silver powder coat. The increased bore is the foundation of the displacement boost, providing a significantly larger area for combustion.
The Requirement for Crankcase Machining
A critical distinction for the S&S 100″ Sidewinder Big Bore Kit is that it requires machining the stock crankcases. To accommodate the larger diameter of the 100-inch cylinder spigots, the engine’s original crankcase opening must be bored out. This is necessary because the size jump is substantial, exceeding the limits of a true “bolt-on” installation. While this adds complexity and cost, the resulting performance gain is well worth the effort, as it allows for maximum bore size within the stock case constraints. This is a key focus for an advanced Harley Twin Cam upgrade.
Unprecedented Power and Torque
The 100-inch displacement, coupled with the proper supporting modifications, unlocks the true potential of the early Twin Cam motor.
Performance Metrics
While stock 88″ engines produce modest power, the S&S 100″ Sidewinder package, especially when paired with performance cams and a high-flow exhaust/intake system, is capable of pushing rear-wheel performance into the 100+ horsepower and 110+ ft-lbs of torque range. This level of power drastically improves roll-on acceleration, highway passing ability, and overall fun factor, making the bike feel incredibly responsive and aggressive. The focus is on a broad, flat torque curve, which is ideal for street riding.
Complete Conversion
This is not a standalone kit. S&S engineered the 100″ Sidewinder kit to be part of a larger performance system. To achieve the 100-inch size, riders often choose to utilize performance S&S cylinder heads (or heavily modified stock heads) and a high-lift S&S camshaft. This holistic approach ensures all components work in harmony to deliver maximum, reliable power. For those targeting the highest performance, S&S often recommends their Gear Drive Cam setup to eliminate the weak link of the stock cam chain tensioners.
The kit targets Harley Big Twin 1999-2006 models, including the Softail, Road King, and Electra Glide families. It is important to emphasize that this specific kit is for the earlier connecting rod configuration and does not fit 2006 Dyna models or any 2007-later models.
In conclusion, the S&S Cycle 100″ Sidewinder Big Bore Kit is the gold standard for riders looking for a significant and robust performance increase for their early Harley Twin Cam. While it requires professional installation due to the necessary crankcase machining, the resulting gain in 100 cubic inches of performance makes it one of the most rewarding and powerful Harley engine upgrades available.
| Product Style | AmericanV-twin Item # | Catalog Number | Store Sku | MFR. Product # | Availability |
|---|---|---|---|---|---|
| Black | 10085926 | 200-6280 | 910-0646 | In Stock: Ships within 24 hours | |
| Silver | 10085925 | 360-0763 | 910-0642 | In Stock: Ships within 24 hours |
This Product Fits
Harley Davidson
Dyna Convertible FXDS 1999, 2000
Dyna Low Rider FXDL/I 1999-2006
Dyna Street Bob FXDB/I 2006
Dyna Super Glide Custom FXDC/I 2005, 2006
Dyna Super Glide FXD/I 1999-2006
Dyna Super Glide Sport FXDX 1999-2005
Dyna Super Glide Sport Touring FXDXT 2001, 2002, 2003
Dyna Wide Glide CVO/SE FXDWG2 2001
Dyna Wide Glide CVO/SE FXDWG3 2002
Dyna Wide Glide FXDWG/I 1999-2006
Electra Glide Classic FLHTC/I 1999-2006
Electra Glide Standard FLHT/I 1999-2006
Electra Glide Ultra Classic FLHTCU/I 1999-2006
Road Glide FLTR/I 1999-2006
Road King Classic FLHRC/I 1999-2006
Road King Custom FLHRS/I 2004, 2005, 2006
Road King FLHR/I 1999-2006
Softail Deluxe FLSTN/I 2005, 2006
Softail Deuce FXSTD/I 2000-2006
Softail Fat Boy FLSTF/I 2000-2006
Softail Heritage Classic FLSTC/I 2000-2006
Softail Heritage FLST/I 2006
Softail Heritage Springer FLSTS/I 2000, 2001, 2002, 2003
Softail Night Train FXSTB/I 2000-2006
Softail Springer Classic FLSTSC/I 2005, 2006
Softail Springer FXSTS/I 2000-2006
Softail Standard FXST/I 2000-2006
Street Glide FLHX/I 2006
