One of the most frequently offered tips I (and others) give is to raise your idle speed when someone has a complaint about performance etc. So I thought I'd drop my idle down to 850 for a couple of weeks to see what actually happens. I didn't drop it to 600 to sound like a Harley, just 850, which is basically the bottom line for required idle RPM.
First off, I gained off idle hesitation. Didn't used to have it. Went back to 1000-1050 rpm on idle this morning, and it went away again when I went to work.
Secondly, for the first time my bike started dying on a cold start up. Never used to happen. I actually thought my LCV was jacked up, until I remembered I lowered my idle. This morning she fired right up and went to high idle like she's supposed to. When I had it set to 850 it wouldn't even go to high idle, I'd have to goose the throttle.
Thirdly, and probably most importantly: When I had it at 850, at a stop light the oil pressure would be basically non existant. It would read about 5 psi on my gauge. I'd have to blip the throttle at a stop light to get the oil moving. Now that I'm back to 1000-1050 rpm. the oil was sitting at 20 psi at the several stoplights I hit on the way to work this morning. I know that oil isn't the primary method of cooling the bike, but I imagine it helps a bit. But more importantly, a bike with no oil circulating is going to reduce engine life, even if it doesn't have a catastrophic failure. We've had members report that they had to shut their bike off during a long traffic jam because it was acting up, I'd imagine low RPM would contribute to their problems.
I know that I've said "some people believe" that low RPM at idle means the oil pump isn't kicking in. I believe it to be true after watching my gauge for a couple of weeks now.
I also know we recommend to raise idle when someone complains about off idle hesitation, and now I believe it after seeing the results.
Finally, and this one I can't prove, just seat of the pants dyno, I have a 20 mile run on country highways when I come to work. This morning I really felt like she ran better over that 20 miles. Can't prove it. Just felt smoother.
I have a friend who has a regular Road Star 1700. His idle is set so low it barely runs. Until this two week trial period, mine was always set at 1000 RPM. He would tease me about it, and my response was always "I don't sit and idle enough to make it worth it to me to drop the RPMs. I'd rather have it run right." After my simple test, I stand by that. We just don't sit around with our bikes idling enough to make it worth the risk of not circulating oil properly, or to put up with off idle hesitation and dying when the engine is cold.
Hopefully this will help someone. We've had some noobs join recently, and at least two of them complained about hesitation, and asked about maps. They may not even need a map, just to adjust the idle.