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How we chose: this guide is research-based, built from manufacturer specifications, safety certifications and owner feedback rather than hands-on testing. How we research.
Before you buy: Parts are model-specific, so always confirm fitment for your bike’s exact year and model, and check local noise and emissions rules. Related guides: full-face helmets for Harley riders, cruiser boots and saddlebags. See current options at RevZilla
A big bore kit replaces your Twin Cam 88’s cylinders and pistons with larger ones to increase displacement, which mainly adds torque. Our three picks are all from S&S Cycle: a 95-inch kit, a 97-inch kit and a 98-inch kit. Check fitment for your exact year (the 95-inch kit below is listed for 1999 to 2006 Twin Cams), and plan for a matching cam and a fuelling tune to get the full benefit.
Best Big Bore Kits For Twin Cam 88 Reviews
Upgraded crank modifications are one of the many features a big bore kit offers. You might not “need” it, but it offers maximum power gains and horsepower. With just a flick of your feet at the throttle, you can instantly feel the larger bore and cylinder.
1. S&S 95 in. Twin Cam Black Big Bore Kit for Harley Davidson 1999-2006 Twin Cam
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Pros
- Comes with a black powder-coated finish
- No need to modify or upgrade the heads for its installation
- No problems with the fitment
- Efficient and high-quality piston cylinders
- The kit comes with adequate equipment.
- It is a one-unit product with high-quality aluminum material built.
- Compatible with models from 1999 to the 2006 models
Cons
- The installation process is a little difficult.
- The price is a little bit on the expensive side
With an optimal displacement of stock Twin Cam 88 ensuring the design, the S&S 95 Black Big Bore is compatible with all models of Harley going as back as to the 1999 classics and fast forward to the 2006 innovative models.
The Black Big Bore Kit comes with all the adequate equipment required to transition your 88in. to 95in. Besides the cylinder, pistons, clips, rings, wrist pins, and base and gear gaskets.
2. S&S Cycle 98″ Silver Big Bore Kit 910-0482
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Pros
- A corrosion-resistant black and/or silver powder coat finish
- It is readily compatible with the fuel-injected system models.
- Employs aluminum castings with a cast-in iron lining that enhances its durability
- The kit comes with gaskets (head, base, and exhaust), rings, cylinders, and pistons.
Cons
- It isn’t readily available at the local auto shops.
- Is a bit on the pricey side
Warranting upgraded, high-end performance results, the S&S Cycle bore kit comes with great installation ease as well. With no sweat-breaking work of boring or splitting the pre-existing cases, the S&S Cycle bore kit can be swapped.
Constructed from premium aluminum castings beside the cast-in iron liners, the S&S Cycle bore kit ensures durability and reliability without offering optimal combustion levels.
The S&S Cycle 98 Bore Kit package includes cylinders, rings, pistons, a head gasket beside the base, and exhaust gasket equipment. The bore kit outlook settles off with a fine black and/or a silver powder coat finish.
3. S&S Cycle 97&Prime, Big Bore Kit Black 910-0205
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Pros
- The kit installation involves no flywheel rebounding
- No crankcase machine installation is required to aid with fitment
- The kit features a piston set, S&S cylinders beside a top-end gasket
- 9 to 10 cubic inch bolt-ons
- Glazed and manufactured pistons are readily compatible with 98cc heads of S&S Super Stock
- Doesn’t requires you to replace your pre-existing gear drive cams
- Comes with an uncomplicated and easy to understand instruction manual guide
Cons
- It could probably use more cam for improved performance.
- After hitting the 1000 mile conservative running mark, you have to increase the main jet size or raise the needle using a washer.
The S&S Prime features a piston set, S&S cylinders, and a top-end gasket beside 9 to 10 cubic inches bolt-ons. Plus, the installation ease is ensured with no crankcase machine installation.
The S&S coated and manufactured pistons make the S&S Prime readily compatible with S&S Super Stock 98cc heads’ stock. With the piston weight for 97in. The kit requires no rebounding the flywheel.
Buying Guide
Just so you can get hold of the right aftermath big bore kit for the twin-cam 88 without having to probe through each option, many of which promise fake claims consequently wasting your bucks, here is why we have assembled a guide for you that offers the “all you need to know” information about the item in question.
The Bore Kit
The kit must include pieces of equipment necessary for the installation. You can not just push in the big-bore kit when you need a top-end. The head gasket beside the exhaust and base gasket and a bore and cylinder with piston and rings must check items that the kit should include.
Installation
On most ATVs (all-terrain vehicles), dirtbikes, or road gliders like Harley, installing a big bore kit is similar to that of the top end. However, models serve as exceptions with the engine case modification requirements that involve an engine builder.
The installation demands heaps of payment in terms of attention to detail, which usually a gear geek or a mechanic can pay using the appropriate installation piece of equipment.
Engine and Crank Modification
To ensure a better kick start and throttle response, you need a big bore kit and have to carry out engine modifications. With the increase in displacement due to larger bore, adequate tuning is required besides piston size and crank modifications.
The engine size goes up by a staggering 18 percent after bore kit installation to ensure your engine doesn’t wear out sooner than its warranted time because of the stress employed by the large piston size on the stock crank components. Make sure to get upgrades to the stock stroke and weight of the crankshaft.
Deck Height
To ensure your big bore’s sparkle isn’t lost with poor non-original piston installation, the Deck height is a must check on non-stock setups because any big bore kit pistons that are incorrect and are not well designed but instead are copies of the original. Besides, often having inaccurately manufactured valve reliefs can create significant damage to your engine.
Conclusion
The big bore kits rehabilitate the moderate mileage engine areas with high mileage and deliver optimal throttle response. Resulting in increased cylinder compressions, more than the stock components usually offer, the big bore kits cordially cause a sizeable boost in cylinder volume compared to the factory manufactured or unchanged combustion chamber volume.
If your budget can’t bend around to accommodate either one of the top 3 picks, we suggest that you don’t sweat and instead save up until next time. Spending a wad to cry out loud, in the end, wouldn’t be ideal. Therefore, instead of going for cheaper alternatives, we suggest that you save up and then make the purchase. We are sure you won’t be disappointed, you can take us up on our word!
With the guide and reviews we assembled, besides the well tested and sought out pros and cons, building your criteria accordingly and picking the right unit at a reasonable price now would be easy. As to which big bore kit best suits your Harley Twin Cam 88 since it is high time that you make the prime move!
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