2024 Kawasaki KX450 and KX450X

Nystrom7
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2/1/2024 8:25am Edited Date/Time 2/1/2024 8:25am

Maybe its just a batch of frames or several different batches that got a problem? 

 

1
BobPA
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2/1/2024 8:43am
I bet you picked up some grunt just repacking the muffler.  People don’t understand how important back pressure is.  Sounds like that zero turn will be...

I bet you picked up some grunt just repacking the muffler.  People don’t understand how important back pressure is.  Sounds like that zero turn will be put off for a year.  Good for you!

Common misconception. Exhaust back pressure is not needed, and is in fact power robbing. Engineering Explained, Steve Morris, and numerous other videos/threads can explain it better than I can. Exhaust length and size are a tuning tool, back pressure is not. There are a few good Reddit posts about it backed by actual race engineers. 

 

If it is needed, why are all drag cars open headers? Pro stock cars are on the cutting edge of naturally aspirated HP.... You do not see mufflers or restrictors in their exhaust setups. 

yz133rider
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2/1/2024 10:05am
I bet you picked up some grunt just repacking the muffler.  People don’t understand how important back pressure is.  Sounds like that zero turn will be...

I bet you picked up some grunt just repacking the muffler.  People don’t understand how important back pressure is.  Sounds like that zero turn will be put off for a year.  Good for you!

BobPA wrote:
Common misconception. Exhaust back pressure is not needed, and is in fact power robbing. Engineering Explained, Steve Morris, and numerous other videos/threads can explain it better...

Common misconception. Exhaust back pressure is not needed, and is in fact power robbing. Engineering Explained, Steve Morris, and numerous other videos/threads can explain it better than I can. Exhaust length and size are a tuning tool, back pressure is not. There are a few good Reddit posts about it backed by actual race engineers. 

 

If it is needed, why are all drag cars open headers? Pro stock cars are on the cutting edge of naturally aspirated HP.... You do not see mufflers or restrictors in their exhaust setups. 

All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque grunt off a corner etc? 

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BobPA
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2/1/2024 10:34am
yz133rider wrote:
All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque...

All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque grunt off a corner etc? 

In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people get mixed up. There are countless YouTube videos explaining it.... And the dudes are much more well versed in teaching than me haha.

 

The Shop

2/1/2024 10:37am
yz133rider wrote:
All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque...

All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque grunt off a corner etc? 

BobPA wrote:
In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people...

In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people get mixed up. There are countless YouTube videos explaining it.... And the dudes are much more well versed in teaching than me haha.

 

So what is the advantage gain by repacking your muffler?   My bike always pulls harder with a freshly packed one.

1
soggy
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2/1/2024 10:53am
yz133rider wrote:
All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque...

All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque grunt off a corner etc? 

BobPA wrote:
In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people...

In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people get mixed up. There are countless YouTube videos explaining it.... And the dudes are much more well versed in teaching than me haha.

 

So what is the advantage gain by repacking your muffler?   My bike always pulls harder with a freshly packed one.

Placebo? Maybe?

it’s quieter so it’s easier to notice the acceleration. 

FGR01
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Fantasy
2/1/2024 11:09am
yz133rider wrote:
All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque...

All the examples given are for wide open applications. I’m not sure but Is it important for part throttle response and low end response / torque grunt off a corner etc? 

BobPA wrote:
In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people...

In short, no it is not important for any RPM range. Scavenging and back pressure are not one in the same and that is where people get mixed up. There are countless YouTube videos explaining it.... And the dudes are much more well versed in teaching than me haha.

 

So what is the advantage gain by repacking your muffler?   My bike always pulls harder with a freshly packed one.

Packing doesn't create backpressure.  Having blown out packing probably increases backpressure and worsens flow because now exhaust pressure is escaping the perforated core of the muffler and travelling all into the body of the can with no escape.

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BobPA
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2/1/2024 11:12am
FGR01 wrote:
Packing doesn't create backpressure.  Having blown out packing probably increases backpressure and worsens flow because now exhaust pressure is escaping the perforated core of the muffler...

Packing doesn't create backpressure.  Having blown out packing probably increases backpressure and worsens flow because now exhaust pressure is escaping the perforated core of the muffler and travelling all into the body of the can with no escape.

Exactly what I was going to say.

bjohnson361
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2/1/2024 11:55am
alycium102 wrote:

IMG 7438 2.jpeg?VersionId=6dpwPnBlddVCCmEdQJ9D2IT3q5EGb2

RCMXracing wrote:
“Eligible units”… be cool if there was a VIN range, but no letter and nothing when punch VIN into recall page. VIN on mine ends in...

“Eligible units”… be cool if there was a VIN range, but no letter and nothing when punch VIN into recall page.

VIN on mine ends in 1236 

Bummer, just picked up my 2024 450 Saturday. Then yesterday they call me about the recall. They have to remove the rear shock and inspect the frame. Great, just dropped $12k on a bike only to have some hack "inspect" my frame for damage and possibly use JB weld to fix it. WTF

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bjohnson361
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2/1/2024 12:13pm
Brent wrote:
Yea I did call the dealer Monday and told them the issue, their employee said they would get back to me. Problem is I have a...

Yea I did call the dealer Monday and told them the issue, their employee said they would get back to me.

Problem is I have a guy from NL here now to train for racing, and waiting for a response or action from Kawi will take weeks if not months, so I just have to get a new motor now and deal with it later.  I need to get this kid back on the track ASAP.   

I was told that Mitch Payton is now going to look into this, as they are helping out with my rider's program...

Still, no one can explain for sure why this happened to a new bike - If you 24 KX450 owners start to sense a loss of power or hear a strange noise, stop riding it and get it checked out.  It only took 1/3 of a lap for our motor to go from perfect to destroyed...Sick

I just picked my 2024 450 up Saturday. I was going to wait a few months before doing any serious riding (turn 47 in March and horribly out of shape lol). I guess I should man up and go run it pretty hard this weekend. Especially now, after hearing about the frame recall. Good luck on your end Brent!

Brent
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2/1/2024 3:31pm

Image 1-17-24 at 10.21%E2%80%AFPM.jpg?VersionId=IYH9

Nchez11
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2/1/2024 3:49pm
Brent wrote:

Image 1-17-24 at 10.21%E2%80%AFPM.jpg?VersionId=IYH9

This is what I’m looking for to fit the 24 kx450 Twin air filter. What filter goes on this?

FGR01
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Fantasy
2/1/2024 6:11pm
Brent wrote:

Image 1-17-24 at 10.21%E2%80%AFPM.jpg?VersionId=IYH9

Some people want pictures pulled down.  Some people also maybe don't want to replace blown up engines.....Whistling

jophis_37
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2/1/2024 7:03pm
crmx105 wrote:
Not sure what the Vin # range is but the issue is near the shock tower. If it's cracked Kawasaki replaces the frame , if it...

Not sure what the Vin # range is but the issue is near the shock tower. If it's cracked Kawasaki replaces the frame , if it isn't cracked they epoxy the frame!!!! Hard to believe but true!

jophis_37 wrote:
I got the notification today.  I plan to inspect the frame myself then drop the bike off at the dealer Friday for them to inspect. They...

I got the notification today.  I plan to inspect the frame myself then drop the bike off at the dealer Friday for them to inspect. They don't have the epoxy kit so they'll have to order it from kawi after the inspection

Did you receive something in the mail?

My riding buddy at the dealer notified me. 

jophis_37
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2/1/2024 8:07pm
alycium102 wrote:
I just don’t see how this “epoxy” mix is a remedy for a potential cracked frame. Like I said before, hopefully this warranty issue carries over...

I just don’t see how this “epoxy” mix is a remedy for a potential cracked frame. Like I said before, hopefully this warranty issue carries over into the warmer months. 

My understanding is the frame will be replaced if there's a crack. But, If there's no crack you get the epoxy kit hack. What would be nice to know is what happens 9 months down the road if it still cracks? Will the epoxy application be critiqued? Will kawi stand behind their product? 

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racinstation
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2/1/2024 8:18pm

Mine is 119 and no recall 

I was told that they were inspecting ALL units, that there was not a VIN range of units that were in question.

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alycium102
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2/1/2024 8:57pm
alycium102 wrote:
I just don’t see how this “epoxy” mix is a remedy for a potential cracked frame. Like I said before, hopefully this warranty issue carries over...

I just don’t see how this “epoxy” mix is a remedy for a potential cracked frame. Like I said before, hopefully this warranty issue carries over into the warmer months. 

jophis_37 wrote:
My understanding is the frame will be replaced if there's a crack. But, If there's no crack you get the epoxy kit hack. What would be...

My understanding is the frame will be replaced if there's a crack. But, If there's no crack you get the epoxy kit hack. What would be nice to know is what happens 9 months down the road if it still cracks? Will the epoxy application be critiqued? Will kawi stand behind their product? 

I was also told today that the warranty for the frame is as long as the bike life. So if it happens later it sounds like they will warranty it. I’ve talked to Deven Raper and he’s got a bunch of hours riding and racing and he’s had zero issues with the frame and is still solid. I think this inspection is just a worst case scenario kind of deal. Idk how many have come forward about it but I know a handful of guys with the bike with zero frame or zero motor issues. Guess we just gotta be thankful it’s a Kawi and not a yomamaha haha

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bjohnson361
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2/1/2024 9:45pm
alycium102 wrote:

IMG 7438 2.jpeg?VersionId=6dpwPnBlddVCCmEdQJ9D2IT3q5EGb2

RCMXracing wrote:
“Eligible units”… be cool if there was a VIN range, but no letter and nothing when punch VIN into recall page. VIN on mine ends in...

“Eligible units”… be cool if there was a VIN range, but no letter and nothing when punch VIN into recall page.

VIN on mine ends in 1236 

Bummer, just picked up my 2024 450 Saturday. Then yesterday they call me about the recall. They have to remove the rear shock and inspect the...

Bummer, just picked up my 2024 450 Saturday. Then yesterday they call me about the recall. They have to remove the rear shock and inspect the frame. Great, just dropped $12k on a bike only to have some hack "inspect" my frame for damage and possibly use JB weld to fix it. WTF

What's with the thumbs down? 

1
2/1/2024 11:53pm
Brent wrote:

Image 1-17-24 at 10.21%E2%80%AFPM.jpg?VersionId=IYH9

who's cage is this? 

Sandusky26
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2/2/2024 3:25am

I don't know how I feel about opoxy on my 11,000 dollar overpriced hunk of shit.

I paid a dealer for "prep" and I unload my bike, and the dealer left the coating on my brake rotors. So now my pads are fucked thanks to Big Rock Powersports.

Would you guys be okay with me smearing a 5 gallon bucket of tar on your roof and handing you a bill?

 

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MXer391
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2/2/2024 6:40am

Not sure if all you guys remember but this isn't the first time Kawasaki had issues with a new model. There was a recall on the '19 or '20 (I forget) 250's for an engine issue related to valve springs breaking. The '21 250's broke clutch plates. The '19+ 450's had fuel pump recalls. I understand these things happen but it sure seems like they happen more often to green bikes. I was really trying to talk myself into one but this is tough. Maybe it's not a big deal, who knows?

 

To Brent, I had a friend who had a low hour '21 KX 250 that broke a clutch plate and destroyed the engine. Took the bike back to his dealer and Kawasaki paid for all the replacement parts but he was responsible for the labor. Just an FYI. 

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crmx105
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2/2/2024 7:49am
burn1986 wrote:

Good thread for the ‘24 KX in particular. I’m sure some have already started shaving lbs off the KX.

https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/How-to-lose-10lbs…,1353858

crmx105 wrote:

Page is gone?

burn1986 wrote:

I guess it is. Weird. It was there yesterday 🤔

Do you remember some of what they did? Guessing tires and exhaust some of it?

1
burn1986
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2/2/2024 8:30am
crmx105 wrote:

Do you remember some of what they did? Guessing tires and exhaust some of it?

Yep, exhaust saved a couple of pounds, going to Michelin tires saved about a pound. Can’t remember all the rest other than titanium, graphics and plastic.

crmx105
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2/2/2024 8:32am
crmx105 wrote:

Do you remember some of what they did? Guessing tires and exhaust some of it?

burn1986 wrote:

Yep, exhaust saved a couple of pounds, going to Michelin tires saved about a pound. Can’t remember all the rest other than titanium, graphics and plastic.

Ok thanks!

burn1986
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2/2/2024 10:10am
crmx105 wrote:

Ok thanks!

It’s just a weird thing with the link. Anyway, it was just a search on here for “Lose 10lbs on a kx…”

crmx105
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2/2/2024 12:40pm

My vin on my 24 is flagged for inspection. I have 8 hrs on it and I don't see any cracks and I am currently 240 lbs but not riding SX. In retrospect Kawasaki didn't waste any time in announcing /acknowledging this which is not always the case and time will tell how big of an issue it is? Some other brands keep things quite and you have to jump through hoops to maybe get something covered. Just saying this because my initial reaction was panic. Lol

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