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The Evolution Engine-Why Did they Scrap It?

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Old Aug 1, 2021 | 10:56 AM
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Default The Evolution Engine-Why Did they Scrap It?

For years, I've heard about how the evolution engine was the most well-made of all the air cooled v-twins. I owned one myself...a used '98 RK classic. It was a great bike.

I'm not in the know when it comes to the complex mechanics and technical specifics of the evo engine, but my question is why did Harley get away from something most everyone raves about? Why not bring it back, or produce an engine with the same traits, since it did so well?

Is it the old Chrysler slant-six theory...made too well, hampering the bottom line?

I'd like some proficient Harley wrenches to chime in and give their thoughts on this. Anyone?
 
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Old Aug 1, 2021 | 11:06 AM
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Originally Posted by Pinelimbs
For years, I've heard about how the evolution engine was the most well-made of all the air cooled v-twins. I owned one myself...a used '98 RK classic. It was a great bike.

I'm not in the know when it comes to the complex mechanics and technical specifics of the evo engine, but my question is why did Harley get away from something most everyone raves about? Why not bring it back, or produce an engine with the same traits, since it did so well?

Is it the old Chrysler slant-six theory...made too well, hampering the bottom line?

I'd like some proficient Harley wrenches to chime in and give their thoughts on this. Anyone?
I'd be interested in what others think, but I view the Milwaukee 8 as a high tech re-do of the Evo.
 
Old Aug 1, 2021 | 11:11 AM
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Originally Posted by Lars_Danner
I'd be interested in what others think, but I view the Milwaukee 8 as a high tech re-do of the Evo.
That fits pretty good

WP
 
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Old Aug 1, 2021 | 11:23 AM
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Originally Posted by Lars_Danner
I'd be interested in what others think, but I view the Milwaukee 8 as a high tech re-do of the Evo.
Well, they are both 2 cylinder engines......
 
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Old Aug 1, 2021 | 11:28 AM
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I think it had to do with going to two cams so the pushrods were at less of an angle and it would be less stress on the valve train. Twin cams can rev a bit better/faster and there is slightly less noise from the cam chest, cutting down on noise emissions. I remember hearing that somewhere but i can't remember where. Its a shame because the evo still sounds like a harley and the early twin cams had a few teething issues. The moco really messed up in 03 with the pressed together crank in my useless opinion.
 
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Old Aug 1, 2021 | 12:20 PM
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Mostly to meet emissions regulations
 
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Old Aug 1, 2021 | 01:18 PM
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To help save the planet?
 

Last edited by IronAss; Aug 1, 2021 at 01:43 PM.
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Old Aug 1, 2021 | 01:22 PM
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Originally Posted by Dan89FLSTC
Well, they are both 2 cylinder engines......
I was thinking that the move back to a single cam from the twin cam was a pretty big reversal.
 
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Old Aug 1, 2021 | 01:26 PM
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Evo retired to make bigger stock engines and HP, what new buyers wanted from the factory. They are still getting bigger every few years.
 
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Old Aug 1, 2021 | 01:30 PM
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Because you people weren’t happy with 80 cubic inches and 65 horsepower.

There’s a bunch who, no matter how much they have, they just gotta have more. Why else the constant inquiries about cams, big bore kits, stroker kits, headers, stage 1,2,3, and so on?

The Evo had reached the practical limit as far as displacement without a major redesign. As long as they were going that far, the MoCo decided they might as well change everything. Some things, like chain driven cams, were to reduce cost by eliminating the labor involved in measuring and matching cam and pinion gears. The change from a bolted flywheel assembly to a pressed flywheel assembly was also done to reduce parts count and cost.
 



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