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2018 KLR650 Blown Top End (1300 miles)

8K views 33 replies 12 participants last post by  DPelletier 
#1 · (Edited)
Hello gang. Has anyone ever seen this problem? I just recently installed the Eagle Mike kit in the subject bike for a friend and did the typical mods to open the airbox top. It already had a free flow DG exhaust on it. The last thing I did was remove, clean and re-oil the air filter.

When I went to reinstall the air filter and was wiping clean the inside of the airbox I noticed the wire mesh permanently mounted between the carb and the filter. Huh? I have never seen this on a motorcycle and it looked nasty so I called a KLR guru and asked what the heck it was for. He said he wasn't sure but it was probably to prevent some random small rock or anything else from getting the the carb. I found that strange since that is what the filter itself does but on a super fine level. He said all KLR's have that screen, they always look sort of nasty but it's not really hurting anything. So, I buttoned up the machine, took it for a test ride and that Eagle Mike kit was impressive. Everything worked GREAT!!

Fast forward no more than 50 miles later and a new owner reports white smoke billowing out of the exhaust. The Kawasaki shop found that that wire mess mentioned above actually rusted, broke into pieces and got sucked into the cylinder. It was obviously made out of some sort of corrosive material instead of stainless or brass. The photo I have seen shows that the screen is brittle and breaking apart in pieces. The quote to repair it is $1,600.00. This bike is hardly even broken in with only 1300 miles. I am shocked that Kawasaki would install anything in the path of the air intake that could rust or come loose. Super disappointed.
 
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#2 ·
I dunno what that mesh is made out of but I've had 3 KLRs over the last 16 years and a close to 100K miles (wow never thought of it that way) and on none of them did that mesh screen give me any trouble nor has it looked 'nasty.' It is strange that it would happen on such a newly minted bike.

sre
 
#6 · (Edited)
Yep, mystifying......the backfire screen is present on all KLR's. I took a close look at one on my 2001 as I tried to remove it for more airflow.....I'd guess it's stainless but can't say for sure. It ended up being such a PITA to remove, I ended up trashing the airbox and having to order another. the mesh was strong and I could barely poke through it with a sharp screwdriver and it took alot of effort with snips and a dremel to cut it.....even when I cut or punctured it, it stayed intact.

I've never seen or heard of any corrosion on that screen and, if anything, it should be oily from filter oil residue and shouldn't be prone to any corrosion. At this point, my best guess would be that it was cleaned with something extremely corrosive... like acid. I think the clue here is "looking nasty".....in your verbal conversation, your guru probably was referring to it being a bit covered with oily residue which is somewhat normal......but if it looked corroded or not, I'd suggest that is not normal at all.

I suppose it's also possible that they changed the screen material at some point but I've not heard of any problems prior to this despite frequenting a half dozen various KLR forums and groups on a daily basis.


Dave
 
#7 ·
...I wonder if driving through something extremely nasty would pull enough corrosive liquid (suspended in the air) through that screen to cause a problem? ....is there any other odd corrosion on the bike? spokes, fasteners? Ridden on the beach, in a salt water spray?


Dave
 
#8 ·
In 36 years of dealing with KLRs I've only seen Stainless Steel flame arrester screens, or maybe they are "stain less" screens like the Gen 1 exhaust header is apparently stain Less steel.

Either way, I've never seen a rusty flame arrester, much less a corroded one on any KLR250, 600 or 650.

The slightly oily flame arrester screens can be useful to see the talcum powder fine dust allowed thru by an under-oiled or Un-Oiled air filter. Is that what he means by "nasty"??

All 4 stroke dirt bikes, atvs & even street bikes with an Oiled Foam air filter that I have ever been around have had a back-fire flame arrester screen of some manner.
So I question how much of a Guru your acquaintance truly is.

https://www.kawasakipartshouse.com/oemparts/a/kaw/5e75486687a8660d8ca5e1e1/air-cleaner
https://www.kawasakipartshouse.com/oemparts/a/kaw/500b5c2af8700223e4796dd1/air-cleaner

I've no idea what could have happened to a 2018 with such low mileage, but I'd like to see all the evidence.

A moderator will probably offer to finish linking or embedding pics into this thread if you sort of try to link them before your 15th posting.
 
#9 · (Edited by Moderator)
Thank you Westman. The guy I called a guru really is just that when it comes to the jetting and other KLR mods. I think the question about the purpose of the screen is something most folks haven't really thought about. Simple man theory is that it's there prevent something from going into the throat of the carb? Although I now know that that isn't the reason, it sounded believable.

I have owned lots of bikes over the years and have never seen a screen on anything other than an ATV. However, most of my bikes were either MX or woods racing machines. I'm used to the area between the carb and filter being fully open and so darn clean you can eat off of it other than filter oil and filter rim grease. I originally asked about this screen because it looked rusty and also because it kept me from inspecting and wiping clean the airbox between the carb and filter which is something I always do.

At the end of the day I'm kicking myself for not digging deeper into the matter of this crappy looking screen before I buttoned the machine up. But my thought was this - The screen is not removable and can't really be cleaned without somehow getting to the front side of it which means you literally have to take the entire bike apart to remove the carb . Then I thought - Well, this is obviously not an intended routine maintenance item and it's not a race bike. The engineers must know what they are doing because this is a legendary tractor of a machine that has proven itself for decades with few changes. So I installed the freshly oiled filter not knowing that something catastrophic was about to happen. I attached the photo here showing this disintegrated screen with pieces missing. By the way, the parts that are still there look twice as bad now as the did when I inspected it in November. Obviously some sort of runaway corrosion problem.

Lastly, the filter had never been removed since the bike was purchased new in November 2019 and had only been off the pavement once during that time. I was the first person to ever remove and clean the filter.
 

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#11 ·
Maybe it was caused by fuel containing ethanol?



Ethanol is corrosive.


Even at 10% Ethanol Gas, which can be up to 10%, that’s 3.06 teaspoons per gallon.

If he ran E-85 in the bike I could see it, but normal Gas that’s 10% or less, hard to see.

But you are correct, if he did run E-85 it would eat that metal up!


2018 KLR 650
Mods in Progress
Clovis NM (till the AF moves me again)
 
#13 ·
Yep, the mystery deepens.......no, 10% ethanol wouldn't do it as there are tens of thousands of KLR's running around using that fuel without issue.

1st filter change and bike never used in any environment that explains the issue? wow........obviously the screen was exposed to some extremely corrosive element at some point whether it was before, during or after assembly.....I'm guessing that you didn't notice any other corrosion anywhere on the bike?

Don't kick yourself too much; hindsight is 20/20 and it would be pretty hard to predict this on a bike that was less than 6 months old.

I'd love to figure this one out but I'm starting to think it will be one of those "unsolved mysteries". :-(



Dave
 
#14 ·
Vision 1: I see a forklift driver unloading a boat in Thailand and dropping a crate of KLR airboxes in the ocean......crate retrieved, airboxes dried out and installed in new KLR's to be sold to unwitting owners.....

Vision 2; I see a KLR idling in a garage beside a forklift battery being charged and ingesting some of the acidic offgassing.....

Vision 3; Dude builds furniture in his shop (where he keeps his KLR stored) and the air has propellants from the glue he uses suspended in it.....KLR is left idling to warm up in this environment several times....

That's all I got. I will say that Vision 3 was a reality with a heat exchanger in my shop; our insulation glue offgassing ate right through it in a short time.


Dave
 
#19 ·
Just 87 Octane fuel and the bike has been in a nice garage from day one. There is absolutely nothing else on this bike that doesn't look brand new including all the surfaces of all parts, aluminum and steel. All hardware looks brand new. Nothing on this bike shows any signs of any corrosion. It has scratches on the plastics from the one off road journey we took it on. Bazaar situation.
 
#21 ·
Near the ocean?

I once ran into a corrosion problem with a customer only 1km from a salt water seaport. The warehouse area was indoors but they tended to leave doors open due to the tropical heat. Please note this customer issue had nothing to do with motorcycles.

jncdi
 
#22 ·
I've spent the last week dribbling fresh sulphuric battery acid on the screen of the heat melted air box every morning & then plugging in the 10 amp battery charger onto a POS battery to fumigate the screen all day.

The screen is dis-colored kinda' white or gray depending on area, not silver like it was. But not a hint of rusty brown.
 
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#23 ·
The implicit assumption is that all screen mesh is the same material. Could be a subpar or cheaper material was used instead of the standard one.

I have seen this a number of times where a supplier will send the "golden sample" to meet the technical requirements and ongoing shipments only meet the price point.
 
#26 · (Edited)
Rick Hall You mentioned an after market exhaust system.

One of the knowledgeable members has often warned that a loose clamp can allow hot exhaust gas to melt a hole in the clean air side of the air box. Is it possible that exhaust gas has leaked into that air box and caused the problem? I notice in the photo that there is a lot of crap sitting around in an area that should be clean.

Or is it possible that a previous owner has replaced the air box with an old weathered air box after noticing that exhaust gas has melted a hole in the original air box? I know the bike has not done many miles, but some bikes get sold at pretty low mileage
 
#27 ·
@Rick Hall - Just curious. Since you were the last person to work on the bike is the owner trying to blame you? Situations like this is why I hesitate to work on anyone else’s bike.

.
 
#28 ·
this is one odd duck of a failure mode. I tend to think it got run without the foam filter for some time. still how the screen corroded / dissolved is crazy, But the battery which could be ham fisted / spilled is only 6 inches away give or take. Still not sure how a spilled battery gets liquid into the box. uh if someone could run a quick test?? jus kiddin

A overcharged battery outgassing is another potential causal area. but still . . . just about have to think what we observe of that screen had to be chemical in nature. Chipmonks would have to chew their way through to foam to get at the delicious metal screen. I have heard of mice chewing on wiring so . . . .

***no chipmonks were harmed in the typing of this message. ****

line6distortion
 
#30 ·
looking at the pdf pic again, the mesh screen looks like it is clogged with saw dust or similar, again pointing to the foam filter not being there or mis installed.
I agree. What I would like to know is what exactly the rider was doing at the time of the failure. How fast, on the throttle etc?? Did the bike slow down and speed up again before the failure?

Looks like the screen is totally plugged. Is it possible, that at speed enough suction on the intake stroke could have pulled the screen into the engine? That's my long distance diagnosis. We're not getting the whole story here. I think this is more an owner issue than a Kawasaki issue. Expensive mistake.

.
 
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#32 ·
Without the basket the foam would be useless. How would you attach the foam? No way you could make that mistake and if you did then you shouldn’t be doing your own maintenance.
 
#34 ·
On the screen I removed, you couldn't push that bolt through it without a hammer - I really think the issue is something corrosive severely compromised the screen - pics show it falling right apart and I had to pick, cut and pull every strand to remove mine - it wasn't going anywhere without a fight. At the end of the day, I couldn't remove it all cleanly so I tossed the box and got another on ebay.....left the screen alone after that!

Dave
 
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