2024 Kawasaki KX450 and KX450X

quadzrulebro 1/10/2025 3:51pm
1/10/2025 3:51pm Edited Date/Time 1/10/2025 3:55pm
JazzyJJ wrote:

We're similar in weight, what did you go to up front?

quadzrulebro wrote:
I went from the stock 5.0Nm to the optional stiffer OEM 5.2Nms.  With stock valving, this worked for me, but I’m 6’3”.  If you’re not sure...

I went from the stock 5.0Nm to the optional stiffer OEM 5.2Nms.  With stock valving, this worked for me, but I’m 6’3”.  If you’re not sure, buy just one spring and see if that is enough to give you the holdup you need.  I just installed a Race Tech Gold Valve kit, and the instructions told me to go back to stock fork springs, which surprised me, but I haven’t gotten a chance to try them yet.  

JazzyJJ wrote:
Thanks for this. That's interesting that they said to go back to stock springs. Maybe I just go the gold valves as it's slightly more money...

Thanks for this. That's interesting that they said to go back to stock springs. Maybe I just go the gold valves as it's slightly more money but if I can use the stock springs it'll be the largest upgrade for my buck.

I installed the Gold Valve setup myself in my 2019 forks.  I never tried the shock because once I got the right spring on it, I was happy with the shock.  It was a fun winter project, so I’m doing it again this year.  I bought a nitrogen tank and regulators so I can do the shock myself now, too.  The forks are done and the shock is ready to be put back together now.  I’ll be able to service my suspension on my own moving forward.  So far, the shock is way less complicated than the fork.

Rocky Mountain has great videos on YouTube that walk you through the whole process.

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NicNak
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NicNak 1/10/2025 7:23pm
1/10/2025 7:23pm
JB500 wrote:
This has me interested, I’m close in weight/age/class as well. I’m 40, intermediate and about 162 without gear. I got a ‘24 late fall and won’t...

This has me interested, I’m close in weight/age/class as well. I’m 40, intermediate and about 162 without gear. I got a ‘24 late fall and won’t ride it till spring so I have no basis for how the suspension actually feels. What rear spring rate did you end up with that was the ticket, and based on your experience, at my weight I should probably do the same? And to clarify, front springs seemed good for this weight?  

alycium102 wrote:
The stock shock felt great at first for indoor riding at cedar lake arena but once i went outdoors in the bumps and such is where...

The stock shock felt great at first for indoor riding at cedar lake arena but once i went outdoors in the bumps and such is where i really noticed how bad it wanted to kick. Plus like we said before you wont be able to get your static/race sag numbers where you want them. Honestly idk if i would follow the race tech spring rate thing, unless they updated it. When i checked in spring it was telling me i should go almost 2 spring rates down which no way jose haha. But yeah we only went down one spring rate on the shock and it feels amazing and im 170-175. We tried going down a spring rate in the forks and it was way too soft so we put the stock fork springs back in. So good. Youll love it once you get it all worked in. 

mikemike214 wrote:
Curious how it’s gonna feel, I called factory connection this morning and they said it should be good to go without changing springs. I pick it...

Curious how it’s gonna feel, I called factory connection this morning and they said it should be good to go without changing springs. I pick it up tomorrow so I’ll see if I can get the sag right 

The internals are different on the 23 to the 24s. Just valving not like anything design related. My forks are set up with a different setting than my old bike 

LouisianaMotocross 1/10/2025 8:13pm
1/10/2025 8:13pm
DB505 wrote:
Anyone know if the 22 forks will work on 24/25?  Asking cause if I go that route I my put my 22 coated/racetech valved forks on...

Anyone know if the 22 forks will work on 24/25?  Asking cause if I go that route I my put my 22 coated/racetech valved forks on it!

Trailturd wrote:
I'm running 21 forks on my 24. The older forks have the better coating on the lower legs and some of the internals are better. The...

I'm running 21 forks on my 24. The older forks have the better coating on the lower legs and some of the internals are better. The 24 forks uses a plastic spring cup and the older model is aluminum, the free piston is different, and the compression post/sub valve. Here is a good video showing the differences. 

I much prefer the forks on my 24 vs the older generation(I had a 19). I think some of this is because factory connection did a great job. 

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gscx
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gscx 1/10/2025 8:15pm
1/10/2025 8:15pm

So i just checked my TPS. On the lower end of the adjustment range at .58. I adjusted up to .6 and will see what happens when I ride again. Some day the weather won't be 30f with a foot of snow.

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The Shop

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MXer391
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MXer391 1/11/2025 8:51am
1/11/2025 8:51am
alycium102 wrote:
Forks will feel amazing but I’d go down a spring rate on the shock. Unless you can dial it in really well but you want be...

Forks will feel amazing but I’d go down a spring rate on the shock. Unless you can dial it in really well but you want be able to hit the static/race sag numbers quite like you want 

MXer391 wrote:
^^^This. I'm a 165 lbs 40B rider as well. I have my race sag set at 105 but I bet I'm 50ish with my static. My...

^^^This. I'm a 165 lbs 40B rider as well. I have my race sag set at 105 but I bet I'm 50ish with my static. My spring is pretty far up the threads. I talked to a tech at Factory Connection and he seemed to think it was fine to have that much static sag so I've been riding it that way for now but I think I would benefit from going down a rate. 

mikemike214 wrote:

The forks seem ok? I figured I would have to go lighter on each end but didn’t get to ride it yet.

I only got to put about 5 hours on mine before the weather turned. It felt really stiff the first ride or two. I had to back everything out front and rear. It has softened up quite a bit now so I am still making adjustments but have had to go back In a few clicks last ride and it was working decent. I probably wouldn’t make any fork spring changes until I tried a softer shock spring first. 

Golfnut721
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Golfnut721 1/13/2025 2:41pm
1/13/2025 2:41pm

Since we are on suspension right now, lets see if there are any trends in spring rates. I think racetech has me a little soft in the front. decent in the rear. I did install the gold valves.

Lets list our weight our REAL riding ability and style and what spring rates we are running, Ill start

230lbs moto/arena C class vet(42) .51 in the front 6.3 in the rear.

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crc245
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crc245 1/13/2025 6:57pm
1/13/2025 6:57pm Edited Date/Time 1/13/2025 7:04pm

2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork height, clicker changes. Stock 54 Nm shock spring, 104/105mm sag. 24 hrs on the bike/stock components (so about ready for a fluids refresh), but overall happy once fork oil was increased.

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JazzyJJ
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JazzyJJ 1/13/2025 7:23pm
1/13/2025 7:23pm
crc245 wrote:
2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork...

2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork height, clicker changes. Stock 54 Nm shock spring, 104/105mm sag. 24 hrs on the bike/stock components (so about ready for a fluids refresh), but overall happy once fork oil was increased.

Did you just add some extra oil or remove all the stock stuff and start from scratch?

crc245
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crc245 1/13/2025 7:26pm
1/13/2025 7:26pm
crc245 wrote:
2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork...

2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork height, clicker changes. Stock 54 Nm shock spring, 104/105mm sag. 24 hrs on the bike/stock components (so about ready for a fluids refresh), but overall happy once fork oil was increased.

JazzyJJ wrote:

Did you just add some extra oil or remove all the stock stuff and start from scratch?

Just added to the stock stuff from the old bottle of Maxima 5wt that's been in the motovan for a bit!

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JazzyJJ
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JazzyJJ 1/13/2025 7:32pm
1/13/2025 7:32pm
crc245 wrote:
2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork...

2025 KX450 (Same stock baselines as 2024), SoCal tracks, 30+ Slow Expert, 180 lb., 6' tall. Stock 5.0 Nm fork springs, +25cc fork oil, flush fork height, clicker changes. Stock 54 Nm shock spring, 104/105mm sag. 24 hrs on the bike/stock components (so about ready for a fluids refresh), but overall happy once fork oil was increased.

JazzyJJ wrote:

Did you just add some extra oil or remove all the stock stuff and start from scratch?

crc245 wrote:

Just added to the stock stuff from the old bottle of Maxima 5wt that's been in the motovan for a bit!

Awesome thanks. I'm a noob at handling my own suspension stuff

quadzrulebro 1/13/2025 7:43pm
1/13/2025 7:43pm Edited Date/Time 1/14/2025 4:24am

6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a syringe through the air bleed hole.  Forks up 3mm above the clamp. Stopped the bottoming, but the feel isn’t as plush.  Just installed Gold Valves, and they recommended I go back to the stock springs, which surprises me.  

In the back, since I’m so tall, they recommended a 5.9kg spring.  No one makes a 5.9 that I’m aware of, so I bought a 6.0 from Race Tech. At this point, the valving is stock (and works really well), but I’m currently installing a Gold Valve kit on the shock to match the front.  I’ll let you all know how I like it when I have some feedback to share.

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JazzyJJ
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JazzyJJ 1/14/2025 6:26am
1/14/2025 6:26am
quadzrulebro wrote:
6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a...

6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a syringe through the air bleed hole.  Forks up 3mm above the clamp. Stopped the bottoming, but the feel isn’t as plush.  Just installed Gold Valves, and they recommended I go back to the stock springs, which surprises me.  

In the back, since I’m so tall, they recommended a 5.9kg spring.  No one makes a 5.9 that I’m aware of, so I bought a 6.0 from Race Tech. At this point, the valving is stock (and works really well), but I’m currently installing a Gold Valve kit on the shock to match the front.  I’ll let you all know how I like it when I have some feedback to share.

Thanks, please report back. I have a spring for my weight on the shock, trying to decide if I want to open it up and revalve or not. I haven't even ridden the thing yet so I'll probably feel it out and see what I think before making more work for myself. 

startbuttonarmpump 1/14/2025 8:27am
1/14/2025 8:27am
quadzrulebro wrote:
6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a...

6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a syringe through the air bleed hole.  Forks up 3mm above the clamp. Stopped the bottoming, but the feel isn’t as plush.  Just installed Gold Valves, and they recommended I go back to the stock springs, which surprises me.  

In the back, since I’m so tall, they recommended a 5.9kg spring.  No one makes a 5.9 that I’m aware of, so I bought a 6.0 from Race Tech. At this point, the valving is stock (and works really well), but I’m currently installing a Gold Valve kit on the shock to match the front.  I’ll let you all know how I like it when I have some feedback to share.

JazzyJJ wrote:
Thanks, please report back. I have a spring for my weight on the shock, trying to decide if I want to open it up and revalve...

Thanks, please report back. I have a spring for my weight on the shock, trying to decide if I want to open it up and revalve or not. I haven't even ridden the thing yet so I'll probably feel it out and see what I think before making more work for myself. 

Ride the bike! Go put a few hrs. on it, get a feel for it, that way you know what the changes did.

4
quadzrulebro 1/14/2025 2:37pm
1/14/2025 2:37pm
quadzrulebro wrote:
6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a...

6’3” 215lbs winning +50B MX (love that contingency).  Currently running OEM optional .52nm fork springs and added 25 ml fork oil to each fork with a syringe through the air bleed hole.  Forks up 3mm above the clamp. Stopped the bottoming, but the feel isn’t as plush.  Just installed Gold Valves, and they recommended I go back to the stock springs, which surprises me.  

In the back, since I’m so tall, they recommended a 5.9kg spring.  No one makes a 5.9 that I’m aware of, so I bought a 6.0 from Race Tech. At this point, the valving is stock (and works really well), but I’m currently installing a Gold Valve kit on the shock to match the front.  I’ll let you all know how I like it when I have some feedback to share.

JazzyJJ wrote:
Thanks, please report back. I have a spring for my weight on the shock, trying to decide if I want to open it up and revalve...

Thanks, please report back. I have a spring for my weight on the shock, trying to decide if I want to open it up and revalve or not. I haven't even ridden the thing yet so I'll probably feel it out and see what I think before making more work for myself. 

The valving in the forks was soft, for sure, but the shock was fine.  Honestly, I never would have messed with the valving, but it needed the oil changed anyway, and since it is wintertime, I was just looking for a project.  Unless you’re bored like me, you probably just need to get the spring rate right in the rear.

1
Trailturd 1/14/2025 3:26pm
1/14/2025 3:26pm Edited Date/Time 1/14/2025 3:27pm

2024 Kx450x, 190-195lb, Open A AMA WHS Series. The X comes with softer springs than the regular model. Swapped the stock X springs for stock KX450 springs. Went from 4.8n/mm front to 5.0 and rear 52n/mm to 54. Running 350cc oil in fork, fork at first line in clamp. Revalved by Precision Concepts.

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grunkster
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grunkster 1/14/2025 3:30pm
1/14/2025 3:30pm

How is the x? Is vibration bad for long offroad events?

Trailturd 1/14/2025 3:37pm
1/14/2025 3:37pm
grunkster wrote:

How is the x? Is vibration bad for long offroad events?

I honestly don't even notice it and I run solid bar mounts. My practice bike is a non counter balanced KTM 250sx 2 stroke so that might have something to do with it. 😆

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nch209
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nch209 1/17/2025 11:44am
1/17/2025 11:44am

More of a nissin guy myself… but gotta wait till the snow is gone before any results can be had…

IMG 6830 4
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MX529
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MX529 1/17/2025 12:59pm
1/17/2025 12:59pm

Huge shout out to Factory Connection for the new rear spring rate 5.7 and complete revalve.. and the quick turn around.. 

 

These guys are thee best,  not only in suspension but rider support, they will take care of all your needs  

Now? have some wrenching to do.. can’t wait to get it back together.. too bad  the weather isn’t going to cooperate in the south east this weekend to test it out


At least she’ll be fresh and ready 😁 🏁🏁


 

Trailturd 1/17/2025 1:17pm
1/17/2025 1:17pm
nch209 wrote:
More of a nissin guy myself… but gotta wait till the snow is gone before any results can be had…

More of a nissin guy myself… but gotta wait till the snow is gone before any results can be had…

IMG 6830 4

Same. Best upgrade I made to my 24 was putting the nissin from my old kx on it.

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crc245
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crc245 1/17/2025 1:32pm
1/17/2025 1:32pm

LOVE me the Brembo on the 24’+ 450’s! I have a complete Nissin assembly off a 2023 if anyone wants to trade straight across…

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JB500
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JB500 1/18/2025 8:14am
1/18/2025 8:14am
alycium102 wrote:
Yeah the fork felt good to me anyway. I left the fork springs stick and had my guy play around with internals and got it to...

Yeah the fork felt good to me anyway. I left the fork springs stick and had my guy play around with internals and got it to me is really swell like. That stock shock spring wanted to boot me over the bars a lot. We went out on hi speed quite a ways on the stock one and it was better but not quite where I wanted or needed. 

Duke28 wrote:

The stock shock kicks like hell. I’ve gone for a ride more than once. 

alycium102 wrote:
Glad I’m not the only one with this experience and I’m 170 pounds. We tried about 2 turns out in hi speed before we just went...

Glad I’m not the only one with this experience and I’m 170 pounds. We tried about 2 turns out in hi speed before we just went to a softer shock. Now it’s amazing. 

Can you share the spring rate that you changed to from stock? 
Thank you. 

quadzrulebro 1/18/2025 9:14am
1/18/2025 9:14am Edited Date/Time 1/18/2025 9:17am
grunkster wrote:

How is the x? Is vibration bad for long offroad events?

Trailturd wrote:
I honestly don't even notice it and I run solid bar mounts. My practice bike is a non counter balanced KTM 250sx 2 stroke so that...

I honestly don't even notice it and I run solid bar mounts. My practice bike is a non counter balanced KTM 250sx 2 stroke so that might have something to do with it. 😆

I gotta be honest, I haven’t noticed any vibration, either, and I came from a 2019.  I’m mostly a moto guy, but one of my last races of the year was a 2 1/2 hour off-road race.

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RGIII
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RGIII 1/22/2025 11:20am
1/22/2025 11:20am
TooTallJason wrote:

I'm a sucker that almost paid full MSRP for 24 right when it came out.  

I have no regrets. 

I'm in the same boat, but I still love it so far!!

1
LouisianaMotocross 1/24/2025 10:31am
1/24/2025 10:31am

Rocky Mountain had the tusk first line air filters on sale for $9 for our bikes. Normally price $24. I bought 4 of them. 

1
quadzrulebro 1/24/2025 11:09am
1/24/2025 11:09am
LouisianaMotocross wrote:

Rocky Mountain had the tusk first line air filters on sale for $9 for our bikes. Normally price $24. I bought 4 of them. 

Thanks for the heads up!

LouisianaMotocross 1/26/2025 7:29pm
1/26/2025 7:29pm

I am not a clutch abuser at all but I am coming up on a year with the bike with the stock clutch. Do y’all replaced these proactively or wait until you feel some slippage? I don’t feel like the performance of the clutch is degrading at all. 

quadzrulebro 1/26/2025 8:10pm
1/26/2025 8:10pm
LouisianaMotocross wrote:
I am not a clutch abuser at all but I am coming up on a year with the bike with the stock clutch. Do y’all replaced...

I am not a clutch abuser at all but I am coming up on a year with the bike with the stock clutch. Do y’all replaced these proactively or wait until you feel some slippage? I don’t feel like the performance of the clutch is degrading at all. 

I race motocross and had the stock clutch in my last KX450 when I sold it with 100 hours on it.  If it ain’t slippin’, run it!

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Golfnut721
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Golfnut721 1/31/2025 12:43pm
1/31/2025 12:43pm

Any new maps out there? I'm still trying to find a dealer to flash my 2024 ecu to the 2025 parameters.

XtremeElMaxwell 1/31/2025 1:36pm
1/31/2025 1:36pm
Golfnut721 wrote:

Any new maps out there? I'm still trying to find a dealer to flash my 2024 ecu to the 2025 parameters.

I know Keefer put out an updated map for the 25 but you can't make the ignition adjustments on the 24 because you're limited to +1. Is flashing the 24 ecu to the 25 parameters an option?

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