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Discussion Starter #1
Hey guys, I'm noticing now that it's quite warm outside that once the bike is hot from running on the highway for 20 - 30 minutes and I am at a light in first, clutch all the way in, the idle seems very high. Is this normal for a 650? I have a 2000.

Thanks,
Dan
 

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how high of an idle do you think you are at? My idle is is pretty well set, unfortunately I do mine by ear if it's ever off.
 

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Discussion Starter #4
generally not high. if your idle increases with increasing temp, you are lean. what other mods have you made?
I definitely don't think it's running lean... the carbs were rejetted and tuned for a Hypercharger and HK DDs exhaust and the exhaust was removed but the jets stayed. It's also backfiring a bit, so it's running rich. I'll put the exhaust back on once I'm done the probation on my permit, I don't want to attract any extra police attention lol!

I called my bro and he thinks way back when he may have sped up the idle, so I'll need to check the book on how to turn it down a bit and see how it acts.
 

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Discussion Starter #5
how high of an idle do you think you are at? My idle is is pretty well set, unfortunately I do mine by ear if it's ever off.
That's just it, I can only go by ear and this is my first bike, but if this was a car, I'd guess it was working at 1500 RPM give or take once the bike is warmed up and driven for a few minutes. When you first start up and close the choke after a minute, the idle speed seems fine... but once I drive it for a few minutes and stop at a red light, it's running pretty fast imo.
 

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I definitely don't think it's running lean... the carbs were rejetted and tuned for a Hypercharger and HK DDs exhaust and the exhaust was removed but the jets stayed. It's also backfiring a bit, so it's running rich.
actually, both rich and lean can cause backfiring, each for different reasons.

you left the HC on but went back to stock exhaust. the HC will flow alot of air, but without the exhaust moving freely there is much less scavenging which affects combustion chamber flow, and vacuum through the carbs. this will then affect the slide operation. flowing less fuel through main jets and the idle jets. as a temporary fix I would turn the fms out a quarter turn until theissue stops
 

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Dan, adjust idle when hot engine. When I put choke off after a ~ minute (cold engine), idle is very low. Engine is not warm enough for corrrect idle level what is when hot engine.
I use my diy throtle locker to keep idle rpm nice when warming up engine (couple of minutes)

Br. kane
 

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Kane67 is correct. Idle adjust when hot. Colder engine idle will be lower until warm up.

Keep choke open slightly to keep colder engine idling high enough so it does not stall.

Adjustment knob is behind the petcock under the (front) carb.

Get the hot idle set to how you like it or 1050 to 1150 RPM.

Mine will run around 850 to 900 with the choke off and cold.
At least for the first 3-5 minutes or so.
 

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Discussion Starter #11
Amazing, thank you guys and thank you for the photo! I'll definitely try this when I get home tonight after the commute and the bike will be good and hot. Thanks all!

Dan
 

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Discussion Starter #12
Thanks again for your help guys... got home lastnight and turned the idle down quite a bit to a sound I thought sounded a lot more normal in the sub 1000 range. Now the engine sounds way less stressed at lights, I just found it always sounded like I was accidentally turning the throttle all the time lol! And no problems this morning starting her up... the usual 1 minute warm up with choke and slowly closed her down and off I went.

Thanks again :)

Dan
 

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Sub one thousand range is still too low for these bikes.

1100 rpm is about perfect. Maybe a shade lower but not much .

If you like it the way it is now by all means keep it....
 

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Discussion Starter #14
I don't have a tach on the bike so I'm just adjusting to a healthy sound, I think I know what I'll be buying this winter ;)

Dan
 

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I can share with you the vendor I purchased mine on ebay from.

Not expensive, simple ( baby could do it hook up) just have to make a mount for it.

Since you have a 650 classic like mine I may be able to hook you up with a piece of black plastic to use as a mount.

Free just pay for shipping via US postal service. why wait ?

Enjoy a tach now. Comes with an hour meter function too. :cool:
 
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