question about the new 103 engine

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Dec 26, 2011 | 11:26 PM

#31

Bluehighways

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Joined: Feb 2010

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From: Southern California

Quote:

Originally Posted by jo_mama

a trap door air filter assembly. what will they think of next? it is easy to understand why you have to re-jet or retune after replacing a/c or pipes. has there been a test using different a/c to see which one flows the best, or do you reach a point where you just can't flow anymore air because of the size of the throttle body?

Yea, after you remove a stock air cleaner that has one of these doors in it you can be pretty certain that it'll run leaner. Essentially you're removing a variable Choke Blade from the Air Intake. But this doesn't apply to the OP's bike because none of the Fuel Injected engines need a Door in the Air Cleaner . . . no Float Bowl = no HC evaporation emissions of any significance to worry about.

All things being equal (which they usually are not) any given Throttle Body will flow a fixed amount at WOT at (and this is important) any given pressure difference across it. One can "assist" matters by smoothing out, and to a certain extent managing the intake and exit from the Throttle Body with the use of things like Velocity Stacks on the Intake and Anti-Reversion designs on the Manifold after the Throttle Body. But as long as you don't have to deal with competition rules that specify a maximum diameter; simply boring the Throttle Body is usually the most cost effective solution.

Last edited by Bluehighways; Dec 26, 2011 at 11:31 PM.

Dec 26, 2011 | 11:33 PM

#32

traveler

Seasoned HDF Member

Joined: Jun 2005

Posts: 12,946

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From: Colorado Springs, CO

If you want the 103 to actually earn it's money, you need to do the followng:

Intake
Hi flow mufflers
Cams
Tune

If you're happy with it stock, that's great! Save some money.

If you rode mine ONE TIME, you wouldn't be happy with your stocker anymore....just sayin'.

~Joe

Last edited by traveler; Dec 26, 2011 at 11:45 PM.

Dec 26, 2011 | 11:43 PM

#33

Bluehighways

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Joined: Feb 2010

Posts: 3,400

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From: Southern California

Quote:

Originally Posted by justine120

this may be a dumb question, but i'm still learning...

does the new 103ci engine mean that the bikes don't need to have stage 1 done after market? or does that mean that the bike can still have this done? thanks for any help guys...

I'd still have it done . . . Replacing the Air Cleaner probably won't do all that much by itself. On the other hand; replacing the stock exhaust system WILL definitely change things in a very significant way. As far as performance goes, a Catalytic Converter is just another baffle in the exhaust, but it's NOT a small baffle . . . ergo . . . you will see quite a change if/when you change your exhaust system. That said, I keep my original exhaust up in the rafters of my garage should the day ever come when I need to get an emissions test to renew my registration. If you reprogram the computer, the most bang for your buck, so to speak, is gained by increasing the spark advance (up to a point) and increasing the rate at which it is delivered. Ideally you want the spark advance to be 1 degree less than what it takes to set off the detonation sensing program. Setting off the detonation sensing system will retard the timing further and longer than is desirable from a performance point of view.

All this said, most folks do a Stage I for reasons that have more to do with the appearance and the exhaust sound of the bike than for any major increase in performance. But then again; appearance and the exhaust sound are very good, and in fact excellent reasons to do a Stage I!

Last edited by Bluehighways; Dec 26, 2011 at 11:47 PM.

Dec 27, 2011 | 07:16 AM

#34

dan conner

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Joined: Apr 2010

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i did a stage 1 on an '09 and later added cams--more power and noise and way less gas mileage. just got a '12...going to cut the cat out and try the xieds. hoping to cool motor and rider down and not loose much fuel mileage.

Dec 27, 2011 | 08:21 AM

#35

NDBadlands4-2

Extreme HDF Member

Joined: Dec 2010

Posts: 14,778

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From: Badlands of ND

I just did the Stage 1 on my 103 specifically to get rid off that cat. I did not need more power really, but I wanted to get rid of all of the heat from the cat and the restricted exhaust. Do not have to many miles on the new setup yet, but looking forward to seeing the difference this spring.

Last edited by NDBadlands4-2; Dec 27, 2011 at 08:21 AM. Reason: spelling

Dec 27, 2011 | 11:12 AM

#36

traveler

Seasoned HDF Member

Joined: Jun 2005

Posts: 12,946

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From: Colorado Springs, CO

The 103 and 96 are the same engine....same cam, same everything except for 3 items:

Automatic Compression Releases in the heads
Screamin Eagle Primary compensator
Oil Cooler

The stroke is exactly the same, at 4 3/8. The difference is in a tad bit more bore. The 96 has a rated compression of 9.6 to1....the 103 is rated at 9.2 to 1. So, basically the same.

The Screamin Eagle SE255 cam is the stock cam that comes in the 110 engine.

Very nice addition and well worth it....but it likes compression releases.

For 2012 all touring bikes come with the 103 engine. 103's that are added by the dealer can very, as there are variants you can get with higher compression, hotter cams, etc. "Stage 4" 103 is rated at 10.5 to 1 Compression and uses the SE 259 cam, I believe.

~Joe

Last edited by traveler; Dec 27, 2011 at 11:17 AM.

Dec 27, 2011 | 11:21 AM

#37

qtrracer

Ultimate HDF Member

Joined: Jan 2008

Posts: 6,532

Likes: 132

From: SoCal

Quote:

Originally Posted by traveler

A bigger bore piston with the same sized combustion chamber and the same stroke will yield a higher compression ratio not lower, something is off somewhere. Or the head combustion chamber size is different too.

Dec 27, 2011 | 11:24 AM

#38

Kowan

Ultimate HDF Member

Joined: May 2010

Posts: 7,882

Likes: 5

From: So California

The compression ratio for my 96 2008 FXCWC is listed as 9.2:1.

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Dec 27, 2011 | 11:49 AM

#39

traveler

Seasoned HDF Member

Joined: Jun 2005

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From: Colorado Springs, CO

maybe I had them backwards.....either way, it's a mild CR.

Dec 27, 2011 | 03:37 PM

#40

keith_stepp

Banned

Joined: Oct 2009

Posts: 20,823

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From: Nowhere

Quote:

Originally Posted by justine120

does the new 103ci engine mean that the bikes don't need to have stage 1 done after market? or does that mean that the bike can still have this done? thanks for any help guys...

The two things (displacement and stage 1) don't have anything to do with each other. Nor does this have anything to do with the concept of "need".

The better questions would be:

Will the new 103ci engine benefit from a stage 1? Answer: Yes.

The implied question... Does a 96ci engine "need" a stage 1? Answer: No.

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