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Discussion Starter #1
I'm curious on how you fine people set your idle correctly (950rpm - 1050rpm). I cleaned and synced my carbs, readjusted the idle by ear, but am unsure if it's actually set to the correct spec. I bought a cheap digital RPM gauge for 10 dollars off ebay but I'm pretty sure it's inaccurate (shows my idle as being excessively higher than what it is).

How do the dealerships do it and I'm wondering if they would quickly adjust it for me if I dropped in.
 

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The idle does sound high but that's the way the Vstar is made. A lot of people want to idle down the get that "Harley sound", but very bad for our bikes. A low idle does not build enough oil pressure to keep things properly lubricated. The Vstar is a duel fire ignition, meaning it fires twice per stroke. This helps with emissions to burn any fuel left in cylinder. Most tachometers are set up for single fire ignition. Your tach is reading twice the true RPM. So if tach shows 2000 it's actually 1000. Hope all that made sense.
 

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Discussion Starter #3
The idle does sound high but that's the way the Vstar is made. A lot of people want to idle down the get that "Harley sound", but very bad for our bikes. A low idle does not build enough oil pressure to keep things properly lubricated. The Vstar is a duel fire ignition, meaning it fires twice per stroke. This helps with emissions to burn any fuel left in cylinder. Most tachometers are set up for single fire ignition. Your tach is reading twice the true RPM. So if tach shows 2000 it's actually 1000. Hope all that made sense.
Thank you. But if my digital tach is set on single fire ignition, but my bike is duel fire ignition, then if the tach is showing 2000rpm, wouldn't the bike actually be 4000rpm? (note: bike is NOT set to those specs. Just using to follow example)
 

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A tach set to single fire ignition will display ignition fires and converts to RPM. So if tach picks up one fire per revolution in a minute then RPM would be 1. On our bikes the ignition fires twice every revolution so it would show 2 RPM even though it was only 1 cycle of the ignition stoke. I'm sure I'm not explaining this very good, it's in my brain, just can't put it in words very well. 😀
 

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A tach set to single fire ignition will display ignition fires and converts to RPM. So if tach picks up one fire per revolution in a minute then RPM would be 1. On our bikes the ignition fires twice every revolution so it would show 2 RPM even though it was only 1 cycle of the ignition stoke. I'm sure I'm not explaining this very good, it's in my brain, just can't put it in words very well. 😀
I believe what you are trying to say if it read 4000 rpms because it fires twice per stroke it would actually be 2000rpm. Divide by 2 because it fires twice per stroke.
Rpms sound pretty high by ear. Need to be higher than you think
 

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Discussion Starter #6
Okay I believe my tach has the option to set it to "the spark plug fires two times per revolution", which is the option we want right? Whatever it displays will be the true rpm right?
 

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Discussion Starter #8
Okay so here's my results. I set my digital meter to "fires once per revolution" because the meter wraps around 1 spark plug wire, therefore only reads the reading from 1 spark plug, which fires once per revolution. I stopped raising my idle at "840 - 900" rpm on the meter, because i feel like my idle is pretty high from the sound of it. Please watch the video i just created to let me know if the idle sounds about right to you or if it sounds too high or too low please. Keep in mind I'm going off sound because meters can be faulty.


Thank you.
 

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Sounds like a sewing machine as many have compared it to. Was the engine fully warm. I would still go up just a tad too get closer to the 950 rpm mark. Yes it sounds high, but it's correct to maintain proper idle oil pressure.
 

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Discussion Starter #10
Sounds like a sewing machine as many have compared it to. Was the engine fully warm. I would still go up just a tad too get closer to the 950 rpm mark. Yes it sounds high, but it's correct to maintain proper idle oil pressure.
Engine was fully warm. 25 minutes on the hwy straight to home.

Okay was just checking to make sure the high-sounding idle sounded normal to you's since I don't have another vstar to compare it to lol
 

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Engine was fully warm. 25 minutes on the hwy straight to home.

Okay was just checking to make sure the high-sounding idle sounded normal to you's since I don't have another vstar to compare it to lol
Mine sing pretty high also. It is good for an old guy like me that doesn't quite have the hand coordination that i used to have. Can let out clutch without gas to roll it in the garage.
 

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Discussion Starter #12
Mine sing pretty high also. It is good for an old guy like me that doesn't quite have the hand coordination that i used to have. Can let out clutch without gas to roll it in the garage.
Okay great. I was worried I would end up causing overheating issues, because I noticed when my idle is set high, if I ride the bike on a hot day for 20 mins on the hwy, then park it for 5 mins and then start it, I get a pop noise coming from the engine. Yet it doesn't do this when my idle is set low (from what I noticed anyways). I cleaned out my carbs, changed the plugs, air filter, oil filter. And still does it. The entire bike is stock with no changes in the carbs except cleaning.
 

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another way to do this: if someone has the same bike with the idle properly set

ride the bike till its warmed up, find a flat/level place to ride it, let the clutch out from a stop in first gear, and see what your no-gas (clutch speed) is on the speedometer. If should be the same for all VS1100 bikes with the idle set the same

when I got my 650 after a while I thought the idle was too fast, so I turned it down quite a bit till it sounded "better".

I noticed when I compression braked the bike slowed down faster, and I liked that, did not have to get on the brake as much when stopping.

Later when I learned it has to be 1200 rpm on a Vstar 650 I set it back to the proper idle speed, and immediately noticed my clutch-speed was faster, and my compression braking was like the throttle was slightly cracked open (it was, the idle screw was higher).
 

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the weight of the rider would not affect your clutch speed

wind would not affect the speed much going that slow, because 1st is geared down so low it has lots of torque to the wheel.

the only thing that would throw it off is going up or down a hill, could try it in one direction then turn around and go back the other way, like in a parking lot.

if its below 10mph there might not be enough resolution on the speedometer to get a good measurement - might have to put a smart phone or GPS on the bike to get an accurate reading
 
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