Stage 1?

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Jan 2, 2012 | 09:41 PM

SwitchHD

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Road Captain

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From: southern cali

Stage 1?

Hi, Can someone please explain exactly what a "Stage 1" enhancement is? Sorry if it's covered elsewhere--if so, maybe direct me in the right direction. Thanks.

Jan 2, 2012 | 11:22 PM

djl

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From: san antonio

Quote:

Originally Posted by kennethjohnsonart

Hi, Can someone please explain exactly what a "Stage 1" enhancement is? Sorry if it's covered elsewhere--if so, maybe direct me in the right direction. Thanks.

Typical Stage 1 is also often, and affectionately, referred to as the "Harley Tax". There is some untapped performance bottled up in the stock engine by the restrictive air intake and exhaust. The problem is exascerbated in the later models which have come set up with leaner A/F ratios each year making the engines run hotter. Used to be you could open up the air cleaner and exhaust and throw on a simple fuel managment device to add fuel and you were good to go. However, now, the later models require a more sophisticated fuel managment system and some dyno time to set them right with the free flowing air intake and exhaust.

Short answer; Stage I is a free flowing air intake and exhaust to replace the restrictive OEM systems but the engine will still run hot without some fuel adjustment; IAW, a tune.

Jan 3, 2012 | 09:16 AM

SwitchHD

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From: southern cali

Got it, Thanks djl

Jan 3, 2012 | 10:24 AM

grbrown

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From: Bedford UK

I would just like to add to djl's words. Harleys have suffered from environment-related restrictions since the 1980s (possibly earlier?!). While the regulations have got much stricter over the years, technology has got more sophisticated, but much better at meeting them.

In addition to the things djl mentions, the cams are tuned to help keep down engine noise, also on my 1990 Evo the ignition timing was seriously compromised. So to any 'stage 1' I would add a change of cams and retuning ignition timing. Setting up (even of a carb bike) can be done best on a dyno.