My FXDC 07 has now been running with the TMAX & Autotune for a while and it is a winner. Still, I lowered the idle to 750 rpm and I only find better running conditions than with the original 940 rpm or so... I just wonder how much lower can you take it without having problems with the engine. Why do you want to do that (you might say)? Well for many reasons, from fuel economy to harley sound to engine overheating (not now in winter), but it is good to know, to improving the 1st gear engagement thus avoiding the typical "CLUNK" and so on.

Just wonder if someone has tried it, adjusting the idle lower than 750 rpm...(FYI @750rpm the rectifier is feeding more than 14 Volts to the battery and the oil pressure light is not on).

Happy New 2008 to all!!
Spanish Flyer

 

Good Luck

 

When I was in Wildwood, NJ for the "Roar To The Shore" there was a dyno trailer. A guy wanted his bike dynoed. The first thing the tech did was to bring the guys idle back up to 950-1050rpms.
Said it needs to run at that rpm range for the oil to circulate properly. I'm not an engineer but if my bike is suppose to run at 950-1050rpms than that's good enough for me.
How much fuel to you think you'll save, is it going to idle that long? It does make the bike sound better.

Happy New Year

Mike

 

Pull one of the plug wires............ That outa drop it to to about 350 rpm at idle

I can see what you are trying to do, but I would be concerned about the heat management, and oil circulation at too low of an idle.

It wasn't a Harley, of course, but my old Honda was designed to idle at 900-1000 rpm (water cooled). HD designed your heat management system, partly around their idle specs.

Please, let us know how that works out for you.

DougJ

 

As the others said ... I wouldn't drop my idle ... as much as I want too cos it does sound cool ... it also puts a lot more pressure on the bearings and pistons at lower idle (less momentum) ... so more pressure and less oil .... I can live with burning valves out by frigging with intakes and pipes ... but bearings/gudgen pins/rings ... they get expensive and difficult to fix

 

Thanks a lot for your response; it is nice to know people care, but really, I just wonder if your statements are based on facts or just because you heard some one saying....
I doubt very much that the old carburetted bikes had a better oil pump than the actual one and of course we are talking about an engine idling, not producing handfulls of power.

And if the oil pressure is too low, wouldn't the oil warning light come on? (I don't have a pressure gauge).

Still, I'm only asking and will only bring-up or lower the rpm after I get assurance of what is good or bad for the engine and of course some explanation of why this is so.

Best Regards,
Spanish Flyer

 

If I remember correctly these newer engines have a port where oil sprays out of and lubes the cylinders.
You could lower your rpms til the oil light comes on then adjust the rpms to your liking but like I said before if it's suppose to be that way the it's fine by me.
Too each his own.

You could go to the newsgroups and ask there, but be warned, read the FAQs first. alt.motorcycles.harley, rec.motorcycles.harley

 

I guess I am most concerned for you in hotter weather, when the Heat Management System kicks in and starts doing it's thing....
Dunno, as said please let us know how this works out for ya. It is already gonna drop your idle down to below 800 rpm when the head temp goes way up.

DougJ

 

I have gotten to stage 2 of heat mgmt here in FL and I have to say it was an odd experience, not to mention my jeans just about caught on fire sitting in traffic..I could not imagine whagt the bike is going to "TRY" to do with an idle that low going into Heat Mgmt.. Best of luck....I am going with these guys....900-1050 rpm sounds just fine for me.

 

I would agree with Doug. In the Dallas heat and traffic the heat management systems saves our engines. If I am stopped in traffic which is most of the time during the summer a good sync oil and the management systems helps tremdously. I wouldn't screw with the idle to sound cool.Not toadd insult to injury just ask the 96ci baggers about heat issues we need all the help we can get.