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Only $10 for all 2026 SX, MX, and SMX series.
Yowza
Did the bike run on it's side for any amount of time? Someone posted on here a while back if they sit for a while bike should be turned over while holding the kill button to get oil pumping?
Run on its side? Like I crashed & it was running while laying down? No it didn’t.
I mean that kind of makes sense but how long is a while? I ride quite a bit & I do go back & forth between bikes but I’ve been riding this one only for the last month or so. Raced it Saturday then Sunday on the site lap it didn’t make it
Yes during a tip over. Regardless that stinks! I believe on the 19-23 model some were going back to the roller bearing rod setup. That may be an option? Also an engine builder told me to run a 50 weight multi grade in bikes with plain bearing cranks. Not saying that would have prevented it? Good luck with everything!
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thanks man. Interesting you say that. Maxima makes a 20w-50 oil & i was using that for a while but it seems to turn into like a sludge material in the bottom of the clutch so recently went back to 10w-40.
Yea it is unreal how these bearings suck. but my buddy told me it's the same bearing they run in vehicles & they go forever. He said if they starve for oil they are shot. I race pretty competitively & have had good luck with my kawi's since 2019 so we'll be alright. I put a crate motor in that bike & have my mechanic splitting & getting a parts list. The whole top end looks great actually. Head, cylinder, piston
Have you guys seen oil blow by the crank case vent?
Noticed oil on the van floor, looked up and it came from the vent tube, had got on the lower shock pretty bad.
55 hours. Ran fine that last moto. Oil change every 5 hours.
You sure it isn’t shock fluid?
Not shock fluid. Now I did get a kick off a bigger jump my last lap, rode the rev limiter pretty long which I never do unless I need to.
Yea that's the overflow. Too much oil in the bike. Probably did not quite get it all drained out then after doing that a few times it has a tad too much oil in it & blows it out the overflow. I'm not 100% certain that's what happened but that's a possibility.
That, or possible piston/ring blowby. If the cylinder or rings are worn, the crankcases will be under constant pressure, forcing some oil out the vent tube.
Did a compression test. Was 75 psi. Internet said 60 to 114psi based off a 12:5:1 compression ratio. I'll do a leak down tomorrow.
Put my camera down there. Everything looked good, plug looked good.
Found no smoking gun with the leak down test.
I'll put my eyes on the oil pump, make sure that's good.
What if the case vent got pinched, built pressure then released? I did find it in between pull arm and shock bottom.
That could do it too.
25 KX 450SR with 60 Hours & 25 KX450 SR with 14 hours - Does anyone have issues with bolts coming loose on these bikes? Specifically the subframe bolts? I have to tighten them every time I come off the track. The same with the exhaust bolts. I ran a long moto on Thursday and one of the subframe bolts snapped and I'm going to have to drill it out. My steering stem nut likes to loosen up frequently as well. I have it torqued to right spec and if I over tighten the steering gets too tight.
I was having the issue with lower subframe bolts. Tapped and Replaced with bolt not oem stuff and it’s been fine.
I have a 25 SR with 71 hours and I did lose the subframe bolt once around 20 hrs but it was right after servicing the shock so I think I just didn't torque it enough. I haven't had any issues since then. I've never had issues with the exhaust or steering stem. I am pretty good at checking most of the bolts right after the first few rides but other than that, I ride it and generally have no issues.
Just picked up a new 2026 KX450. Other than the usual new bike prep, any tips or suggestions on what the new KX needs?
If you are going to run the stock filter set up def get some Twin Air or some other after market air filters. The stock filter compresses paper thin on against the air box. If you want more power removing the screens from the stock muffler helps considerably. I used a flexible wood bit going in from where it fits to the header pipe to get the center one and a regular wood bit on the muffler tip side to rip the screens out. The wood bit grabs the screens without disassembling the muffler.
Pit Row
I safety wire the exhaust so I don't have to over-torque fittings on the frame that I don't want to worry about.
Blue locktite everything you can think of before you ever ride it . You will never lose a bolt. If you don't. You will lose many.
Other that that. Twist the throttle and go! Great bikes stock.
If you use a pressure washer to wash your bike, look at the steering head bearings every 20 hours or so. I get water in there when I pressure wash. Other than that, my 2024 has been flawless.
Good advice so far from current owners regarding TwinAir filters, removing the internal exhaust screens, Loctite, and keeping an eye on steering stem bearings.
I'll add a couple tidbits from my ownership as well. The steering stem bearings last significantly longer if you seal up the frames' inner head-tube: I clean all the grease out first, cut a fork sticker to fit between the races/surrounding the frame walls, and then reassemble with a liberal amount of Maxima/Motorex/BelRay grease. I've found that the lower bearing wear/notching isn't a result of washing, rather moisture in the frame itself.
Mapping is free to test once you download the Rideology app, and I still prefer the original 'Tickle' map that works on 24' - 26' parameters. Even the varying Cha (Chavez) maps are worth trying.
The upper chain roller is unsealed stock and noisy: Replacing it with a sealed/bearing unit is preferable. UFO, Moose, TM Designworks all sell 38mm chain rollers that work well.
If you're going to replace your stock exhaust, invest in a 3/8" drive T-handle and 3/8" 12mm shorty joint/swivel socket: Removing the stock nuts ARE A NIGHTMARE and an extremely tough job with just a wrench/the wrong tools...
Keep an eye on the rear chain guide, as the stock unit will bend/break under real use. I run a Moose/Zeta/DRC style that hasn't failed over hundreds of hours. Plus, the lower block is replaceable and easy to change: Win/Win.
Other needs include a skidplate and better chain. The sooner you install these, the better.
Greasing all the pivots from the get-go is highly advised, as many units come with little/no grease in the linkage/swingarm/axles, etcetera.
A one-piece bar mount keeps bars straight in tip-overs, as the stock design rotates ridiculously easily. No bent bars with the OE units, but also a pit stop every time you so much as look at it wrong. Gotta' figure if you like the bars in the front or rear position, however, as the spread (and bar mount you need) is different between the two.
Tri-Flow in the throttle cables will keep the stockers smoother longer, and on the brass? clutch lever pivot from squeaking/sticking.
I prefer the footpeg brackets in the lower position (6' tall), and grind the tops before installing as my Gaerne boots rub on them. Faster/heavier/SX riders should install the older steel brackets, as the 2019+ aluminum ones can fatigue.
Holes in the side cover/trimming the airbox help airflow, but only if you invest in a better air filter and screen-less AF cage. Tons of 3D printed ones available and a whole TwinAir kit is only necessary if you need more peace of mind. R-Tech sells a vented side cover, available through Pro Circuit, that's cleaner than most can do with a drill. Remove the black rubber airbox puck asap if yours came with it installed already, by the way.
Tons more tips, but out of time for now. I've written about the KX450's extensively if you care to check out some Long Haul reviews:
https://www.dirtrider.com/tests/kawasaki-kx450-long-haul-review/
Cheers and congrats on the new bike - They're GOOD! Great even with some tasteful mods/tuning...
Great info. Appreciate it!
So you’re dealing the holes where the frame is welded to the steering head tube? I never thought of that. That’s a cheap fix for a problem I’ve had with both of my last 2 bikes. Thank you for that!
Decided to do a top end.
Getting conflicting info on head bolt torque. Anyone have a service manual?.
Last Gen is 44ft lbs, motosport has a page with basic torque specs, it says 18-22 ft lb for head bolts.
Damn I've read that about ten times and still don't quite understand the 120 degrees plus 20 degrees. Why not just say 140 degrees. Could someone better explain that for me.
It's read: 120 degrees, plus or minus 20 degrees. Meaning 100 to 140 degrees.
👍
Hell yeah, appreciate that!
Did you buy the digital version online?
Lost my seat collar mount riding this weekend. Otherwise I haven’t had any problems with bolts coming loose.
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