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09 KLX 250 engine stutter at highway speeds

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Anyone get this? Like it's running out of gas? But it's not because I just filled it and I put 20 miles on it. I only seem to notice it at 3/4 to full throttle on the highway. Maybe around 6-9k rpm. It's really annoying and it really doesn't inspire confidence on the highway, which this thing can handle-barely. It's affecting my steering having the bike cut out for 1/16th of a second twice a second.

I've heard of other on the kawasaki forums site mention this as well. My dealer said "oh when it does that, switch it to reserve that means you're running out!"

At first I thought yeah makes sense, but now it does it pretty consistently and with nowhere near to empty tank. Not always, and I really love when it's smooth sailing at 65mph, even if it is at 7-8k rpm, it's smooth.

I plan on getting a dynojet kit and a kdx snorkel for 1st mods, but I'm wondering if I shouldn't take it to the dealer first to make sure I'm working off a good motor setup.

This is my first bike ever and it's the only complaint I have from it so far.

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Yeah I get that, and at first it seems like its the first glance of the tank being low on gas. I think this is a symptom of the bike running lean, everyone says how lean these are from factory. Only thing I can say is I'm glad I'm not running at sea level! At least I'm running at 1000-2000+ ft and have a little air thinning under my belt to help it out. I'm almost half tempted to put a bit of tape over the snorkel holes.....until I get some new jets of course.

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Yeah I get that, and at first it seems like its the first glance of the tank being low on gas. I think this is a symptom of the bike running lean, everyone says how lean these are from factory. Only thing I can say is I'm glad I'm not running at sea level! At least I'm running at 1000-2000+ ft and have a little air thinning under my belt to help it out. I'm almost half tempted to put a bit of tape over the snorkel holes.....until I get some new jets of course.

Hmm, a quick fix to make it run richer...but you're still starving it for air. It'd be a good experiment just to run to see if it fixes this stutter problem.

I am at about 450' elevation. Central Texas. I should just order this dynojet kit and do the airbox mods. Don't have the $$ for the pipes yet, but I'm willing to bet I'll see performance gains and it'll get rid of this stuttering.

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could be, but I doubt it.

Open yours up and look! C'mon it's not a pain in the ass or anything.:thumbsup:

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mine does the same thing, not very consistent though like a hic-up once in a while, maybe something to do with all the vent hoses also, going in and out of the tank and carb, and smog canisters, or maybe just dirt in the carb

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I don't think its the dirt thing. I think its the company given asthma thats given to this bike. Thing actually has decent power they just choke it to death. The pipe isn't great, but its not horrible either. Not that far off from alot of other 4 stroke machines. But the intake is all wrong. SMOG crap, crankcase vent hose, backfire screen (is this common in modern day 4 strokes now or just this bike? Cuz I've never seen it before), super thick dense air filter, tiny snorkel holes, small tapered needle, then to top it all off they lean out the jetting.

Poor thing doesn't get a break.

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I'm still tempted to bring it to the dealer before doing the dynojet kit. The guy who sold me my bike called me today just to see how it was doin, he said just bring it on in. I dunno we'll see. If this is just a symptom of being too lean from the factory, then that's BS. I shouldn't have to deal with that on a stock bike with 1000 miles.

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After doing the DJ kit install I took the backfire screen out and I didn't notice quite as much surging as it had done before.

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After doing the DJ kit install I took the backfire screen out and I didn't notice quite as much surging as it had done before.

Thanks. I put in a TwinAir filter today. I don't believe I over oiled, but it still hiccuped. After an hour of running around the city, then back on the highway, it didn't hiccup at all. It's intermittent.

If it isn't gasping for air, could it be it's running too rich? Maybe I will try running with no airbox cover just to see if it happens again. Obviously I won't run it normally without it until I rejet.

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You are going in the wrong direction making it more lean. These bikes just like all bikes (race only excluded) are lean. Add in a road use and there are leaner with EPA crap. If you remove the thick air filter, remove the box top or the snorkel, you are just giving it more air. This bike is very lean! After 15 minutes of shut down @ 60*F this bike need choke. Mt KLX is too new for any changes yet but my other bike had same simular issues. Different make but still a DS and after a jetting change ran really well. I suggest at least changing the needle position if you can (havent been in the carb yet) moving it up. Then move to the jet kit, then to a pipe. Air filer is hit and miss on bikes along with the flame screen. By what I can see a pipe should wake this bike up.

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Thanks. I put in a TwinAir filter today. I don't believe I over oiled, but it still hiccuped.

If you oil the filter, throw it back in the bike, and immediately go to take off, odds are you'll foul your plug trying to start it, even if you don't over-oil it. My advice is to clean and oil the filter before putting it away for the night, or at least do it a few hours before you plan to ride.

I believe you said over at KF that you already rejetted? If not, then you should definately do so ASAP. Better flowing filter + no backfire screen = even worse lean condition.

P.S.: Post up pics of your handguards :lame: Black = best :bonk:

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If you oil the filter, throw it back in the bike, and immediately go to take off, odds are you'll foul your plug trying to start it, even if you don't over-oil it. My advice is to clean and oil the filter before putting it away for the night, or at least do it a few hours before you plan to ride.

I believe you said over at KF that you already rejetted? If not, then you should definately do so ASAP. Better flowing filter + no backfire screen = even worse lean condition.

P.S.: Post up pics of your handguards :lame: Black = best :bonk:

No jetting at all. I should probably take a look at the plug. Maybe even buy a new one. What plug should I look for?

I'm thinking I will just order the N1TC needle jet parts and go from there. I don't plan on doing the exhaust too soon, but the bike will run a lot better with 40 dollars in parts. I like it quiet.

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The OE recommended NGK plug would be fine IMHO. But I'd just check it, first. Plugs on bikes go a long way, as I understand it. I doubt you fouled it if you got it to start. I know I cleaned and oiled my filter once and it wouldn't even start.

I like the quiet, too. I ride around my po-dunk town crawling with the 5-0, I don't need to draw attention to myself with an obnoxious exhaust.

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The OE recommended NGK plug would be fine IMHO. But I'd just check it, first. Plugs on bikes go a long way, as I understand it. I doubt you fouled it if you got it to start. I know I cleaned and oiled my filter once and it wouldn't even start.

I like the quiet, too. I ride around my po-dunk town crawling with the 5-0, I don't need to draw attention to myself with an obnoxious exhaust.

If I pull the plug and it looks nasty, can I clean it? I know they need to be spaced properly.

Everyone always says "it's not worth it to just to the kit, you need the $500 exhaust too."

Well, I don't have that kind of money at the moment, and even if I went with a dynojet kit for the 09 250 or the 07 300, I think it'd be totally worth the $50-60 to fix this lean bike and get a little boost. Heck, maybe I'll do the sprocket thing too.

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If I pull the plug and it looks nasty, can I clean it? I know they need to be spaced properly.

Everyone always says "it's not worth it to just to the kit, you need the $500 exhaust too."

Well, I don't have that kind of money at the moment, and even if I went with a dynojet kit for the 09 250 or the 07 300, I think it'd be totally worth the $50-60 to fix this lean bike and get a little boost. Heck, maybe I'll do the sprocket thing too.

Plugs can be cleaned yes. Using discretion on how bad though. If its old and nasty I'd toss it. If its fouled, also toss it. Otherwise a cleaning isn't going to hurt. And yes you need to set the gap on them. .028 - .031" I believe.

The jet kit IS worth it because not only will you properly jet it but I'm sure in the process you'll at the very least pull the snorkel out increasing airflow, and possibly a higher flowing aftermarket filter TwinAir/UNI/K&N. Or removing the airbox lid altogether.

The sprocket is also another cheap and easy performance mod. I would advise doing all of those things at once so you'll get more satisfaction out of it. Doing them slowly allows you to adjust to it and you won't notice it as much. But if your bike is bone stone stock and its not running properly because of leanness and you jet it, increase airflow, and put a smaller front sprocket it on it (either a 12 or 13) and take it out and run it you will notice a much bigger difference as opposed as to just rejetting it and doing nothing else. And then down the road taking the snorkel out, then putting the sprocket on. Know what I mean?

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It is most definately worth the 60 bucks to rejet. I think its far more worth the money for 60 bucks to get a few horsepower versus 500 for just a few more horsepower. The jet kit + removing the snorkel woke the bike up a LOT. As for sprockets... meh, I've been told going smaller that 14 is not good for chain longevity. IMHO spring for a bigger rear sprocket depending on how low you wanna go.

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About how long does it take to change the front sprocket? Is it something you could easily do out at the trails?

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The whole chain wear between using a 13 tooth front and a 45 rear are minor. Just a persons personal care regamine can make a difference with that. Putting a 13 tooth on isn't going to hurt a thing. Ill change front sprockets all day verses rear ones. More money and WAY more hassle. At least for me it is. I actually take the time to completely clean out and regrease the axle and bearings when I remove the rear wheel. Well......even if you don't do that its still 10 times the job. Just a total pain in the ass...oh and did I mention more money? Obviously, mathematically, the more teeth on a sprocket the more weight gets divided up on sprockets and chain making them all last longer... but geeze, not riding the machine on the road keeps the tires from being worn, or taking it outside keeps the plastic from fading. Where does it end? 1 tooth on the sprocket won't kill ya. Even 2 teeth won't. Like I said, even buying 2 cheap aftermarket sprockets and changing them over the course of time is no big deal when compared to a rear one. Chains are no biggie either. They are a dime a dozen. Your always seeing close out prices and what not. Just pick one up. I can't even remember the last time I had to buy a new chain for a bike. Seems I always ended up selling it and getting a new one before the time even came around. As long as you keep them out of sand or mud and keep them lubed and properly adjusted they'll last hella long.

Changing the front sprocket all depends on experience and personal speed. I can just tell you its alot easier than messing with the rear.

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