I have mine set at 950. It doesn't sound like an evo, but sounds better. I have the FP3, and you can set idle rpm based on temp. I left the warm up idle the same, lowered it during normal operating temps, and back to 1000 rpm at higher temps.

I tried 900 and didn't like it, I may try 800 or 850 just to check it out.

 

While I don't disagree with your logic back pressure and torque is a myth. Harleys may perform better with back pressure, but if you truly tackle the whole engine and exhaust from headflow, squish, compression, combustion chamber design, and tuned exhaust, maximum performance will be achieved with less back pressure.

How many race engines designed for maximum output do you see with baffles or other areas designed to specifically increase back pressure? 2 strokes don't count because the expansion chamber is there for different reasons.

 

Yet you should be listened to who offers nothing but speculation and postulating on something you read somewhere by someone no one has heard of.

<srcasm>Yeah, you need to be listened to.</sarcasm>

 

That alone makes *YOU* the king of imbeciles. I suppose everyone who doesn't speak "proper English" that's ever invented anything that the world has found ultimately useful, was full of **** and an idiot.

You should kill yourself so that you don't have to fret over all the non proper English speakers on the planet surrounding you and screwing everything up.

 

, BTW, I speak proper English but don`t brag about it either. It`s only when those who claim to speak it by correcting others, is when I call them out for being grammar ***** all the while they are caught being incorrect themselves.

 

I would be more worried about the crank scissoring.

 

Very well put.

And to LAFO I agree with latrob it is the electrical system which will be lacking. There must be a simple fix on the stator side for this, but Harley is not coming out with it. I asked that same question back in '08, let us know!

 

I could have sworn I read it in my SM, but I couldn't find it. Dynojet warns you in the Powervision software that going below 900 will "cause an oil pressure drop" but I know that's not exactly official. I'll keep looking.

I also agree that the charging system concern is probably the most important, but mine still gives me 13.5v at 900rpm and that's with my Wards fans running too. FWIW, I was playing with the live idle adjust on my Powervision and the engine simply would not go any lower than 800. It didn't stall, it just wouldn't go lower.

I think it's safe to say that 900 is perfectly fine and below that the jury is out, but I see no benefit to going below 900 anyway. You're not gonna get old school potato on stock TC cams.

 

Last time, since no one seemed to read my original post. I am set at 850. I have an oil pressure gauge mounted on the engine. On a 100 deg. day, oil pressure is(was, not running the stock pump anymore) 22 PSI. It isn't going to kill your engine. Charge voltage does drop to around 13.2 at idle, but has not been an issue.
So far, only one person responding has provided anything more than opinion and speculation.

 

Too many answers to quote. I've read all, even the ones about grammar. Guess that's not the idea. Every one is entitled for an opinion no matter what language or grammar level they have.

Still, all comments are valid to keep in mind. I did notice the Fp3 in demo mode gives a warning about going below 900. Guess that alone means something.

I will test my bike as it is, see what temperature reading it's showing, voltage and rpm. Can't measure oil pressure as I don't have anything to measure. Then I'll do the same at 950, 900, 850. Probably engine sound will provide some feedback too.

Still think that all comments are helpful even if some are just repeating what they heard from someone else.