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S&S Cycle
S&S Cycle 84-99 BT 88in 3 5/8in Big Bore Cylinder & Piston Kit - Natural
SKU: S0GE 91-7002
Moderate — 2–4 hours
Description
Part #: 91-7002
Installing this 3-5/8" big bore kit will increase the displacement of stock 80" HD (R) Evolution (R) big twin engines to 88" using the stock 4-1/4" flywheels. The kit includes S&S 3-5/8" bore cylinders, 3-5/8" bore flat topped forged pistons with rings and wristpins, head gaskets, base gaskets, exhcaust gaskets, and instructions. The cylinders are shorter than stock, so shorter pushrods, and shorter manifold will be needed to complete the engine.
MIA's Description
Fitment
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Specifications
| Brand | S&S Cycle |
| Part Number | S0GE 91-7002 |
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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