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...

 

you will get a lot of replies, but you can really perk this baby up. This engine will run really lean to meet EPA standards.

 

In my opinion stage 1 is a must on both the 103 and 110.

 

Because theses engines have catalytic converters, they aren't tuned as lean to meet emission laws. I have not had the stage 1 done on my EG and it runs better than any stock engine I've had. Those that have had the stage 1 performed say the power difference is minimum but the engine runs cooler.

 

Wrong here,these engines are tuned very lean to meet Exhaust Emissions.

 

It's up to you if you want to do the stage 1. If you like the way the 103 performs and sounds then there's nothing wrong with leaving everything alone. If however you're looking for a louder exhaust or just a different set of pipes then you can certaintly do the stage 1 upgrade (pipes, air cleaner, fuel programmer)

 

I did a Stage 1 with a SE Super Tuner on my 103 and noticed a little more power. Nothing drastic but noticable. Ofcourse I did it with about 200 miles on the motor so it wasnt even broke in yet. It seems like its running stronger in the past 1000 miles but Im not sure if its because the motor is breaking in or the fact that I hammer the **** out of it. Either way I think its a good mod. Especially if you plan on any future internal motor work that can benefit from the increase in air flow. Im planning on cams and head work so for me it made sense. Plus the stock pipes just sounded weak to me.

 

No, you are wrong. Please take a few minutes to inform yourself before so thoroughly demonstrating your lack of knowledge on this subject.

These engines are tuned to run at exactly 14.65:1 +/- 0.20:1 at anything less than 50% Throttle, after the engine has warmed up. Cold or when over 50% Throttle, the mixture is quite rich. A 14.65:1 mixture is neither lean nor is it rich. It's called the Stoichiometric or "Ideal Air Fuel Ratio." Do yourself a favor; pick up any book on this subject and/or Google the term. There are all sorts of psuedoscientists and other lemmings on this forum that simply repeat this "runs lean" nonsense without thinking to check. Just because others spew forth this "runs lean" nonsense on a Motorcycle forum doesn't make it true; and you shouldn't repeat it unless you are familiar with the subject . . . which you clearly are not!

Do these engines run a very high temperature top end? Yes! Will over-fueling the engine by running the mixture very rich, cool it down? Yes (but gasoline is a very expensive coolant) Will a richer mixture produce more power? Yes . . . but that doesn't mean that they are running lean and enriching the mixture at less than 50% Throttle doesn't do much if anything that opening the throttle a bit more wouldn't do, and do better, without the fuel economy penalty.

None of this means that the mixture these bikes use when stock is a "Lean" mixture. All 3-Way Catalytic Converter equipped gasoline engines (including Harley-Davidson) have been this way since Volvo/Bosch came out with their Lambdasonde system in the late 1970's. This system was pretty much universally adopted by all automotive manufacturers between 1979 and 1981 and is still the primary means of emissions control that remains in use today. It's also the same system on all those 150+ HP non-Harley Bikes and 500+ HP Cars . . . gee I wonder how they're getting all that HP running the same mixture Harley is using . . . .Duh!

 

I'm going to play the diplomat here... You're both right.

When saying these new bikes run lean, that is a true statement if your point of reference is a pre-emmisions controlled vehicle.

But it's also true if you say stoich is neither lean or rich.

As for HP, those figures are at WOT with mixtures much richer than stoich.

So when the statement is made that newer bikes run lean, I think the implication is that they run leaner than machines of the past.

 

No, actually at WOT they run pretty much the same AFR as they always have (~ 12:1), which is to say quite rich. Pre emissions and current bikes (and cars) both run roughly the same AFR at WOT now, as they did prior to 1968. Only cars (1980+ California and 1981+ Federal) usually do so at 80%+ Throttle as opposed to Harley which does so at 50%+ on their Delphi sourced Fuel Injection systems. At more than 5% and less than 50% Throttle and with a warm engine, the mixture is stochiometric to keep both the oxidizing and reducing catalysts functioning. This is where the EPA/CARB test Cycles live, and where the manufacturer has to target their designs. Once outside of that range the manufacturer can pretty much do what they want . . . and they definitely do! The fuel mixture that gets the maximum power on any given engine is a very very narrow range. The EPA/CARB test cycle is based on a driving route in the Los Angeles area presently called the LA92 and ST01 Test Cycles. (Google that if you want some interesting reading.) Because the Drive Cycle requirements (usually called a "Trace") for speed and acceleration do not require an engine to run over 80% Throttle for cars and 50% for Motorcycles, the manufacturer is pretty much free to do what they want under these large throttle opening conditions . . . and they sure do. This is one of the reasons why you see the kind of power and performance numbers today that are far and above anything from pre emissions vehicles.