Wild Dog Adventure Riding

Technical Section => Make / Model Specific Discussions => Suzuki DR & DRZ => Topic started by: Blou Zebu on November 24, 2015, 09:21:36 am

Title: Burnt Airfilter DR650
Post by: Blou Zebu on November 24, 2015, 09:21:36 am
What happened here? I have no idea

The bike does not backfire regularly, not every day and maybe once, exceptionally twice but never 3 times. And just during the first 3? minutes after firing her up

No issues.

I was about to replace the filter with a new twin air filter and found this Now I do not know what to do!

The black stuff on the inside is semi dry oil

(https://lh3.googleusercontent.com/-4fOpDgCw3QY/VlQOcxpmb7I/AAAAAAAAGkA/uXHz79cv4Dw/s912-Ic42/20151124_095245%25255B2%25255D.jpg)
(https://lh3.googleusercontent.com/-0E1l3O3ukhk/VlQO9E1ueVI/AAAAAAAAGkQ/u7Wn-YbcDd8/s512-Ic42/20151124_095227%25255B1%25255D.jpg)
(https://lh3.googleusercontent.com/-Bn402NMSS1A/VlQOWpALaDI/AAAAAAAAGkE/hKrOG4PEXpk/s512-Ic42/20151124_095304%25255B1%25255D.jpg)
Title: Re: Burnt Airfilter DR650
Post by: LouisXander on November 24, 2015, 09:27:00 am
WTF?? Eerste keer wat ek so Iets sien!!
Title: Re: Burnt Airfilter DR650
Post by: chopperpilot on November 24, 2015, 09:32:19 am
Do you still have the wire mesh screen fitted?


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Title: Re: Burnt Airfilter DR650
Post by: Welsh on November 24, 2015, 09:33:00 am
Have your valves been checked recently?  8)
Title: Re: Burnt Airfilter DR650
Post by: chopperpilot on November 24, 2015, 09:33:26 am
Could it be a chemical burn, from the filter oil you're using?


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Title: Re: Burnt Airfilter DR650
Post by: Blou Zebu on November 24, 2015, 09:34:58 am
Do you still have the wire mesh screen fitted?


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Yes

Valves have not been touched

Not a chemical burn Look at the "white plastic support" That is heat not chemical
Title: Re: Burnt Airfilter DR650
Post by: Poffmuis on November 24, 2015, 09:35:47 am
petrol or oil somehow accumulating in the airbox and igniting at some point? check your breathers and pipelines.
Title: Re: Burnt Airfilter DR650
Post by: Poffmuis on November 24, 2015, 09:36:46 am

Valves have not been touched



km? perhaps check clearance and/or compression.
Title: Re: Burnt Airfilter DR650
Post by: Kykdaar on November 24, 2015, 09:39:37 am
Fuel leak into your airbox via your carb where it ignited and caused the burns you see?
Title: Re: Burnt Airfilter DR650
Post by: chopperpilot on November 24, 2015, 10:35:36 am
You could have had your nuts roasted!


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Title: Re: Burnt Airfilter DR650
Post by: Blou Zebu on November 25, 2015, 05:40:56 am
You could have had your nuts roasted!


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You mean turned them in to pee (only) nuts?

Jig imagine jou bike slaan so onder jou gat aan die brand!
Title: Re: Burnt Airfilter DR650
Post by: subie on November 25, 2015, 05:51:49 am
Jy nie dalk airfilter met petrol skoongemaak. Opstart en het die spulletjie gebrand vir so n rukkie.
Dan moet ek nog steeds dink intake valve.
Eerste keer wat ek hoor van so iets. Sal interresant wees om te hoor hoe dit gebeur het.
Title: Re: Burnt Airfilter DR650
Post by: NeilF on November 25, 2015, 07:38:01 am
 :eek7:
Title: Re: Burnt Airfilter DR650
Post by: Blou Zebu on November 25, 2015, 07:40:12 am
Jy nie dalk airfilter met petrol skoongemaak. Opstart en het die spulletjie gebrand vir so n rukkie.
Dan moet ek nog steeds dink intake valve.
Eerste keer wat ek hoor van so iets. Sal interresant wees om te hoor hoe dit gebeur het.

Ek het dit met seep en water gewas en was nie naby petrol nie

Dalk het die bike geflood en toe ontsteek die petrol?

Die een probleem is ek weet nie wanneer dit gebeur het nie. Erens in die laaste 3 4 maande

Title: Re: Burnt Airfilter DR650
Post by: Kykdaar on November 25, 2015, 07:48:03 am
Jammer jy weet nie wanneer dit gebeur het nie - moes n Lotto kaartjie daai dag gekoop het.

Het jy nog die standard vacuum petcock of n gravity-fed een?
Title: Re: Burnt Airfilter DR650
Post by: Blou Zebu on November 25, 2015, 07:49:38 am
Jammer jy weet nie wanneer dit gebeur het nie - moes n Lotto kaartjie daai dag gekoop het.

Het jy nog die standard vacuum petcock of n gravity-fed een?
Ja steeds die standard vacuum petcock

Title: Re: Burnt Airfilter DR650
Post by: lecap on November 25, 2015, 09:46:34 am
It's not at all unusual for a four stroke to fire back through its intake. Please note that isn't the popping you hear from your riff raff exhaust. A backfire you will only see and hear if you run open velocity stacks.
The backfire is usually contained in the velocity stack and the rubber boot connecting it to the air box and the mesh screen prevents it from reaching the air filter.

I think the following happened here: The engine back fired into the intake as you switched it off. The back fire ignited oily residue in the rubber boot and the lack of air flow allowed the fire to smoulder its way into the air filter and melt some foam and plastic before it died of asphyxiation.
The weird part is you need something to burn in there. Engine oil and filter oil isn't (should not be) very easily flammable.

I have seen the same damage before on a KLE.
Title: Re: Burnt Airfilter DR650
Post by: Blou Zebu on November 25, 2015, 09:48:55 am
It's not at all unusual for a four stroke to fire back through its intake. Please note that isn't the popping you hear from your riff raff exhaust. A backfire you will only see and hear if you run open velocity stacks.
The backfire is usually contained in the velocity stack and the rubber boot connecting it to the air box and the mesh screen prevents it from reaching the air filter.

I think the following happened here: The engine back fired into the intake as you switched it off. The back fire ignited oily residue in the rubber boot and the lack of air flow allowed the fire to smoulder its way into the air filter and melt some foam and plastic before it died of asphyxiation.
The weird part is you need something to burn in there. Engine oil and filter oil isn't (should not be) very easily flammable.

I have seen the same damage before on a KLE.

In other words you are saying it was bad luck? And probably wont happen again?
Do you have any idea what that plastic support should cost?

Vielen dank mein herr
Title: Re: Burnt Airfilter DR650
Post by: Kykdaar on November 25, 2015, 09:49:30 am
Jammer jy weet nie wanneer dit gebeur het nie - moes n Lotto kaartjie daai dag gekoop het.

Het jy nog die standard vacuum petcock of n gravity-fed een?
Ja steeds die standard vacuum petcock



Check of hy nog reg werk. Daai fyn rubber diaphragm binne breek maklik. As hy nog OK is dan dink ek die inlet maak nie behoorlik toe met die verbrandings proses nie wat kan veroorsaak dat die hitte terug slaan op die airfilter.
Title: Re: Burnt Airfilter DR650
Post by: Crab on November 25, 2015, 09:57:32 am
I have a Triumph Tiger 100. There is no choke so the carb is tickled before starting. Once excess petrol ran into the air cleaner and ignited on startup. I noticed the motor running rough and shut it down. Trying to figure out what had happened I touched the metal air cleaner housing and burned blisters on my fingers. It must have been like a furnace inside while the engine was drawing air through the filter.
Title: Re: Burnt Airfilter DR650
Post by: gser on November 25, 2015, 12:17:32 pm
Its called a front fire, a back fire happens on the exhaust side of the engine.