getting a high idle...

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dougie
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Re: getting a high idle...

Post by dougie »

Rode the bike today, 5 degrees C.
After a ride the idle was up to 1500rpm so I brought it down below 1000 by letting the clutch out a bit in 1st gear. It went back up to 1500. Tried it on several occasions.
So I guess the advance unit is OK and I just blew it last time I set the idle. I backed it down to 1000-1100.
Cold weather might be a factor as well. Cold dense air = more oxygen = slightly leaner mixture.
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Garnet
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Re: getting a high idle...

Post by Garnet »

dougie wrote:Rode the bike today, 5 degrees C.
5 C :o ......it was only 4 C out on the balmy Left Coast today................ and I did get a wee ride in. :mrgreen:
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Duane Ausherman
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Re: getting a high idle...

Post by Duane Ausherman »

dougie wrote:Rode the bike today, 5 degrees C.
After a ride the idle was up to 1500rpm so I brought it down below 1000 by letting the clutch out a bit in 1st gear. It went back up to 1500. Tried it on several occasions.
So I guess the advance unit is OK and I just blew it last time I set the idle. I backed it down to 1000-1100.
Cold weather might be a factor as well. Cold dense air = more oxygen = slightly leaner mixture.
Sorry, to only allow it down to 1000 rpm isn't a valid test. You must allow it to drop down to almost not running. Weak springs will allow the bike to rev up from 1000 rpm.

Just cut the ignition with the switch and when it is down to a couple hundred rpm, turn it back on and see what happens.

Don't ignore the possibility that you could have both symptoms at once. We found that often.
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bbelk
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Re: getting a high idle...

Post by bbelk »

I second what Twist? said. I also have an Omega (so no advance issues) but had the high idle at times. It responded well to doing a carb balance along with the idle adjustment after a long ride.
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dougie
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Re: getting a high idle...

Post by dougie »

Duane Ausherman wrote:Sorry, to only allow it down to 1000 rpm isn't a valid test. You must allow it to drop down to almost not running. Weak springs will allow the bike to rev up from 1000 rpm.
Just cut the ignition with the switch and when it is down to a couple hundred rpm, turn it back on and see what happens.
Don't ignore the possibility that you could have both symptoms at once. We found that often.
Thanks Duane.
I will try that next time it isn't so damn cold out, hopefully next week.
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
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George Ryals
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Re: getting a high idle...

Post by George Ryals »

I can't understand why so many airheads are reluctant to tweak their idle mixture 1/8th turn richer just to see if the high idle is caused by a lean condition. We always seem to go for the possible causes that take the most effort to resolve.
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Re: getting a high idle...

Post by Garnet »

George Ryals wrote: We always seem to go for the possible causes that take the most effort to resolve.
What else would we have to fill the pages of Boxerworks with?

Besides I'm a Canadian AND own an airhead. That makes me about the cheapest person this side of Scotland, so naturaly I have the idle mixture sooo freaken lean that it'll barley run.

Don't want to waste gas now. :D
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Duane Ausherman
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Re: getting a high idle...

Post by Duane Ausherman »

George Ryals wrote:I can't understand why so many airheads are reluctant to tweak their idle mixture 1/8th turn richer just to see if the high idle is caused by a lean condition. We always seem to go for the possible causes that take the most effort to resolve.
Once I have the carbs working correctly, I adjust the idle for max rpm and then go just a tad richer, so I agree with George.

I have never seen a change of 1/8th of a turn make nearly enough difference to be the solution.

With a high idle, the first test is for weak advance springs. Why? Because it takes only a few seconds and that is all. One can preform that test much faster than getting to the tool kit. I have done it many times at a red light.

Once it passes the kill the ignition and then turn it back on, it is then time to get the tool kit out. After all, the bike is the proper temperature, or it wouldn't be idling too fast.
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dougie
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Re: getting a high idle...

Post by dougie »

You guys were right, thanks.
Adjusted the idle after a long ride. It sits at 1000-1100rpm all the time.
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
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Re: getting a high idle...

Post by Garnet »

dougie wrote:You guys were right,
:shock: First time for everything. :lol:
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