Backfiring
- hillsy
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Re: Backfiring
Hey 00Vs1400GLP - whilst old mate is having a hissy fit here I went back and re-read your original post.
How high is your idle set? If it is overly high you can get a pop or backfire when you shut the bike down - which is "normal" in the sense that the engine is just cycling past another compression stroke.
How high is your idle set? If it is overly high you can get a pop or backfire when you shut the bike down - which is "normal" in the sense that the engine is just cycling past another compression stroke.
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Re: Backfiring
Good that you have stopped posting your Destructive Attitude,...sad that you feel you must continue to post more of your Baseless Assumption with your Personal Attack.
Just to add, when looking over the Tech Board, a Higher Idle speed ( between 1100 and perhaps 1500 RPM) alone has not been shown the cause of a backfire upon shut down. It has been accompanied by either a Lean Idle Screw Setting (that Herb has mentioned) , or some other Carb Condition making for an abnormal Fuel/Air Mixture or amount thereof.
Just to add, when looking over the Tech Board, a Higher Idle speed ( between 1100 and perhaps 1500 RPM) alone has not been shown the cause of a backfire upon shut down. It has been accompanied by either a Lean Idle Screw Setting (that Herb has mentioned) , or some other Carb Condition making for an abnormal Fuel/Air Mixture or amount thereof.
- hillsy
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Re: Backfiring
I wasnt looking at this tech board - I was referring to my own personal experience with my LC.
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Re: Backfiring
Gee,....I must have missed you posting that information in your last message of Advice.
At least 00Vs1400 GLP was helped out with Advice From A More Broader Based Set Of Experience, ....which is why we are all here, eh?
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Re: Backfiring
the wheels on the bus
go round and round
round and round
round and round
the wheels on the bus
go round and round
round and round
round and round
go round and round
round and round
round and round
the wheels on the bus
go round and round
round and round
round and round
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Re: Backfiring
I don’t have a tach so I’m not 100% sure about the idle speed. Went for a ride for about an hour yesterday though and I think I have a vacuum leak somewhere. While at a stop light, the idle speed would vary slightly. I now suspect this may also cause the lean condition that brought on the backfiring.hillsy wrote: ↑Thu May 05, 2022 9:05 pmHey 00Vs1400GLP - whilst old mate is having a hissy fit here I went back and re-read your original post.
How high is your idle set? If it is overly high you can get a pop or backfire when you shut the bike down - which is "normal" in the sense that the engine is just cycling past another compression stroke.
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Re: Backfiring
Your Diagnoses seems a good likelihood. Is this variation like you report something new? I went back and read your OP and didn't see that symptom. If it is relatively new, has the Backfire after shutdown changed any?00Vs1400GLP wrote: ↑Fri May 06, 2022 2:09 pmI don’t have a tach so I’m not 100% sure about the idle speed. Went for a ride for about an hour yesterday though and I think I have a vacuum leak somewhere. While at a stop light, the idle speed would vary slightly. I now suspect this may also cause the lean condition that brought on the backfiring.
To sleuth this possible leak, I'd start with looking for a leaking Vacuum Hose. Next would be the Seal around the Carb Mounting Boots. Less likely but still possible is the Boot-to-Head connection.
You have a good mechanical approach. Let Us All know what you find with this.
And,...any Updates on getting your Idle mixture Screw operational again?
- hillsy
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Re: Backfiring
Sounds like your carbs are coming off so let us know how you go with getting the mixture screws out.
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Re: Backfiring
While searching for a possible vacuum leak, look closely at the hard rubber intake manifolds between the head and carb.
After 22 years they could be cracked. They are pretty thick, so smearing them with RTV could seal any possible cracks.
After 22 years they could be cracked. They are pretty thick, so smearing them with RTV could seal any possible cracks.
- hillsy
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Re: Backfiring
They also have o-rings between the manifold and head and these are worth inspecting as they are likely to have perished.
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Re: Backfiring
There appears to be a little dry rot on those. Probably won’t have time to dig into for a couple of weeks. We’ll see.
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Re: Backfiring
Does this mean you are working on the Removed Carbs?00Vs1400GLP wrote: ↑Fri May 06, 2022 4:42 pmThere appears to be a little dry rot on those. Probably won’t have time to dig into for a couple of weeks. We’ll see.
Inquiring Minds Wanna Know. ( that's a modified line from the Enquirer)
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Re: Backfiring
Not working on the carbs yet. Real job and work around the house is getting in the way.
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Re: Backfiring
I hear you on that. Priorities being what they are, my "toys' have to sometimes get Back Burnered.00Vs1400GLP wrote: ↑Sat May 07, 2022 4:02 pmNot working on the carbs yet. Real job and work around the house is getting in the way.
At least your Bad Boy seems Rideable,...yes? You'd need a Break from those nagging "need-to-dos"
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Re: Backfiring
Rideable, yes. Just could be running/looking a bit better.Designer wrote: ↑Sat May 07, 2022 4:50 pmI hear you on that. Porites being what they are, my "toys' have to sometimes get Back Burnered.00Vs1400GLP wrote: ↑Sat May 07, 2022 4:02 pmNot working on the carbs yet. Real job and work around the house is getting in the way.
At least your Bad Boy seems Rideable,...yes? You'd need a Break from those nagging "need-to-dos"
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Re: Backfiring
Dang,...If we were closer, I'd help you get your Bad Boy running like a fine watch.00Vs1400GLP wrote: ↑Sun May 08, 2022 7:42 amRideable, yes. Just could be running/looking a bit better.Designer wrote: ↑Sat May 07, 2022 4:50 pmI hear you on that. Porites being what they are, my "toys' have to sometimes get Back Burnered. At least your Bad Boy seems Rideable,...yes? You'd need a Break from those nagging "need-to-dos"00Vs1400GLP wrote: ↑Sat May 07, 2022 4:02 pmNot working on the carbs yet. Real job and work around the house is getting in the way.
As to the .."looking better"...what if you Shaved and Showered before you Ride it?
( I'm pulling your leg again )
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Re: Backfiring
Check that the header bolts are not loose, could also be that the header crush gasket has disintegrated.
Grow old disgracefully young man.
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- hillsy
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Re: Backfiring
True - but you will also usually hear a ticking noise when there is a leak at the exhaust gaskets so it's fairly easy to diagnose.
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Re: Backfiring
Yes, I found that out when talking to A guy on the Purple Board after he installed my 1500 Clutch Springs.
You might. Depends on how loud your Pipes are. Standing three feet away, you might not hear it.
To check if I had a leak, I used a the Carboard "tube" from the Roll of Paper Towels and put it right up close so as to "focus in" my listening, and tune out the Exhaust Note. REALLY made a difference!