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May not be it, but you're describing the issue I had with my 09 KX450 exactly word for word. It ended up being caused by me routing the wiring harness on the wrong side of a bracket after I had taken the gas tank off, and it eventually wore through in a very tiny contact point that wasn't visible easily, and a wire would short out on hard landings (maybe frame flex?) after I had been riding a while, and it would bog/die, but restart after like there was no issue. Rerouting and a little electric tape solved it after I replaced the fuel pump, plug, and capacitor trying to solve it before finally eyeing the harness with a more careful eye.
Ok, my fuel pump decided to stop firing over the weekend. What have we been using for a replacement? Any aftermarket ones of decent quality, or is the much pricier OEM worth it?
Replaced the flakey pump on my 23-SR with the All Balls fuel pump kit (47-2061) and it's been fine since.
Did it die completely?
I’m having trouble restarting after it’s hot recently
I have narrowed it down to not hearing the fuel pump after a quick tap of the starter button
Never dies once it’s running
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Just wouldn't restart after it got nice and hot after 2.5 hours of the Vurb 500E. Thankfully once I was back at my pit, not on the side of a hill 5 miles out. Same thing, couldn't hear fuel pump firing, unplugged/checked all my connections, charged the battery yesterday and after a few tries I hear it prime and the bike fires up.
Yo! I just figured I'd share this since I saw this thread go to the top. My buddy just hit 200 hours on his 2019 KX450 - stock bottom end with one top end around 140 hours. Other than the top end, I believe he's only gone through steering head bearings, chain guards, and other normal wear items...it's been a solid bike for him, and he's a fast local 30+ A/B guy.
that is absolutely wicked. The bikes built pre-covid are better than the current ones honestly.
Yeah, I think you're right about that. I have a '24 KX450 and I am not expecting the same experience as my buddy, lol. Thankfully, I'm blessed to be able to have lots of bikes, so I spread the hours out amongst the bikes and only have ~25 hours on the KX (which I'm not riding all that much these days). Time will tell!
Prado just took his shirt off 😎
Ok, replaced my fuel pump, made it through 2 practice sessions, and it started up for another go, but now it's bogging and popping, sometimes dying as soon as I hit the throttle. So it seems to me like something is still getting hot and failing. What else has anyone had to do to theirs? Pissed because I haven't had a bike have issues since my last Kawi in 09.
Are you running T4+ by chance? I’m pretty sure that’s what happened with mine but haven’t had the chance to go riding and check if just running pump gas makes the issue go away.
Nope, 91 pump. Really feels like it has to be something electrical getting hot and breaking down, fuel pump clearly wasn't firing before, and was spotty when it cooled down, I replaced it with the all balls kit, fired immediately and ran, now this is the first time I've ridden since, and I rode 2 10 minute sessions with no issues, and when I went to restart (an hour after the last session) it barely sputtered, then would idle but bog/pop when I revved it or just die.
I've never paid attention to how long the fuel pump normally fires, but noticed it was inconsistent when I'd tap the starter. Double checked all my connections, couldn't see any loose/bare wires on a quick visual check.
It stings a little more when I prepaid for tomorrow's race and got refused a refund for tomorrow, and it was going to be the first time my wife has ever seen me ride.
Sounds like a possible electrical issue if it surfaces once it gets hot .
I’d check tje coil first then go down the list of electrical components from there .
There is a known problem with T4+ right now that causes exactly what a lot of you are experiencing with bogging and fuel pump issues. Do not use T4+. They are currently making new batches.
I keep losing this chain slider bolt for some reason. I put new loctite on and cranked it down Friday night after noticing it was loose the weekend before. Looked down after my last moto on Saturday and it was gone. Do you guys have this issue with these bikes?
Clean the area and threads well with contact cleaner, and apply some blue Loctite . You shouldn't have to do much more than snug it up - you don't want to strip it!
My 22 did the same. I always carried an extra in the toolbox. Checked it when I adjusted the chain.
That's literally what I did haha. But I guess I will try again. I actually stripped the bottom one and had a buddy of mine put a thread insert in it. That one is solid and has no issues. Maybe I'll have him do the same for this one.
Pit Row
Remind me again why Kawi felt the need to spend millions in R&D and throw this awesome platform in the trash? Seems to me like this bike worked great and no one has had much success on the new bike. They should have just kept refining the 19-23 and made it a few more years! What was wrong it with it?
Nothing wrong with either generation. I do like the 19-23 better and I still have my 19. I don’t put much stock in pro results.
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