88 inch Evo?
88 inch Evo?
Anyone ever build one?
I've been looking at all the parts that I would need to build one and I'm not finding 3-5/8" bore cylinders that are stock height. Any cylinders with 3-5/8" bore are for the 96" stroker motor.
I've been looking at all the parts that I would need to build one and I'm not finding 3-5/8" bore cylinders that are stock height. Any cylinders with 3-5/8" bore are for the 96" stroker motor.
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From: Tejas
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From: la la land jerzey
3-5/8 == 4 5/8 is a 96 inch but if I remember I will look for standard height jugs
we found the 89 is almost as fast and its good for twice the engine life against the 96 just so you know < heat and respracating weights are the reason
we found the 89 is almost as fast and its good for twice the engine life against the 96 just so you know < heat and respracating weights are the reason
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Pretty sure 3 5/8 turns into a spigot bore which is the weak area of a Evo. Ran an a 89" for years and it was not babied, S&S flywheel in a 80" is the best bang for the buck. A company called Revolution performance has cylinders/pistons in a Nikasyl application, heard good and bads about the product.
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80-88 inches is not enough to make much of a difference.
Last time I did an Evo just went .010 over with high compression pistons and a cam with Baisley ported heads,my FXR ran like a scalded dog.
Last time I did an Evo just went .010 over with high compression pistons and a cam with Baisley ported heads,my FXR ran like a scalded dog.
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https://www.sscycle.com/products/88-...rinkle-finish/
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89” 4 5/8 stroke IS worth doing over just high compression pistons. I never liked boring the spickets on stock EVO cases.. the swept volume responds really well to low duration high lift cams. In a light bike, I’d shoot for 10.5:1, something in the 260 range for duration, 590-615 lift for a cam. Heads put your money in really good valve job, good rockers and set up with good springs just right for the cam. Maybe a quick clean up in the ports but don’t sink baisley or megaflo money into them. I’d guess with good tuning your in the 101-105 hp, 110 ft lbs.
If it’s a heavy bike go 9.7ish:1. Go with about 575-590 lift 25- duration.. probably 100ish ft lbs of torque 90-100hp. In a light softail that’s a mid to high 11 second bike.
If it’s a heavy bike go 9.7ish:1. Go with about 575-590 lift 25- duration.. probably 100ish ft lbs of torque 90-100hp. In a light softail that’s a mid to high 11 second bike.