My fuel injected bike dies at idle... Kawasaki says its normal?! | GTAMotorcycle.com

My fuel injected bike dies at idle... Kawasaki says its normal?!

Jo_To

Member
Hi everyone,

Long time lurker here. This is my first post so go easy on me. I've been riding a 2011 Kawasaki Ninja 400r for over a year now and I've run into a problem. I was hoping someone here would be able to give some insight... please? I'm reposting this from a thread I created on Reddit in hopes that one of you owns my bike as well... my 2011 Ninja 400r. I noticed that some CBR250r owners are experiencing a similar issue but I can't say for sure if it's the same...


tl;dr, my bike dies at idle when cold and the Kawasaki representative/technician says its normal for small displacement bikes with EFI and there is nothing they can do about it. My bike is still under the extended warranty plan that the original owner purchased. Is this b/s? Any help would be greatly appreciated!



Background Info: For those that don't know, the Kawasaki Ninja 400r was a motorcycle that was only released in Japan and Canada. It is the same as the 2009-2011 Ninja 650r except for a smaller 400cc engine in place of the 650cc engine.


Situation: In late summer of 2013, my buddy low sided my bike on a side street. I rode it in to the local Kawasaki dealer and the mechanic said that it was all mainly cosmetic damage. It was nothing serious, except for the crazy cost of replacement parts (mostly covered by my buddy... but thats another story). Since I hit 12,000km at that time, I decided to let them do the scheduled maintenance as recommended by the manual. However, when I got my bike back, I noticed that my bike's RPMs dropped all the way to 0 rpm as I pulled my clutch in at the first red light or stop sign. I noticed that this usually happened towards the beginning of the ride but it also happened towards mid-ride (15min) a few times. The bike would also seem to have trouble accelerating hard off the line during the beginning of the ride. This went on for about 1000km before I decided to bring her back into the shop for inspection. Initially, the mechanic thought it was the spark plugs or the throttle bodies. After swapping both during the winter, the bike still showed the same problem. There were no error codes detected. The mechanic was able to get the bike to fail on a bench test so he knows I'm not making this up. However, after checking compression and a bunch of other factors (I'm not mechanically inclined enough to repeat everything he said), he was unable to find the source of the issue. He suggests that it's a problem with the ECU, similar to the reason for the recall of the Ninja 300 (apparently, they used to run too lean). A rep from Kawasaki came and checked out my bike but was unable to replicate the problem during the test ride (I was told that the bike was already warmed up due to bench testing). The rep eventually called me to get my side of the story. After explaining all this to him, he said that it's likely that they won't be able to fix my bike. He said that he can hold onto my bike all summer and slowly test and replace every single part but he's not convinced that it will solve the problem... he says he'd much rather have me out enjoying my ride since it operates "perfectly". He further explained that this occurs during cold starts in smaller displacement motorcycles like mine, even if they are fuel injected, because that is simply the nature of these smaller bikes. I went on to argue with him that my friend's Ninja 300 doesn't experience this issue but he insists that they won't be able to do anything about it. My mechanic has been super helpful but suggests that Kawasaki won't do much about this because it wasn't widely distributed model and that it's likely that the only thing that will fix this for me is a power commander. Is what the Kawasaki rep saying legit at all or is he just trying to get out of this issue? Apparently Kawasaki Canada is only a distributor and he's limited in what he can do as a result... The silver lining is that he's willing to compensate me with some parts for my bike (he knows it has been dropped before).


Any help would be greatly appreciated! Thanks in advance!
 
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Not experiencing any issues like that on my ninja 400 so I dont necessarily know if thats normal per se. First thing I would do would be raiae the idle. Its that little knob on the right side of your bike

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Yes. I was going to say the same thing. Download then shop service manual for your bike and read the section for idle screw adjustment. I think idle is supposed to be 1300 rpm on mine. My bike (different from yours) some people were having a stalling at stop issue which was resolved by adjusting the screw as the vehicle breaks in.

There are other things it could be too but the idle screw is a good starting point.
 
From what I understand the Ninja 400 is literally a sleeved-down Ninja 650. If you've read anything about motorcycle licensing in Japan, you'll know why.

Sorry, but what the guy from Kawi said sounds like crap. I haven't heard about it anywhere else. Then again I'm not a mechanic.

I doubt that the 650R and 400R ECUs are the same part number, but it's worth checking the fiche. Apparently the part number on the 2011 650R ECU is 21175-0206. Your best bet is an ECU swap to check it out. There are 400Rs around. I've seen a couple of different ones just around Ryerson.

Keep in mind that if there's any corrosion on the contacts this could effect how the bike behaves cold and, with every extended warranty I've seen, would give them a reason to deny a warranty claim.
 
Hey guys! Thanks for the response and sorry for the late reply... I was out of the country for the weekend and had no internet access. I've tried adjusting the idle multiple times since this started happening to me but it doesn't seem to affect the problem. I've raised the idle all the way to about 1500rpm but the engine still stalls after I open the throttle and then close it. Luckily, it usually only happens about once per ride (its happened twice before) and it's good after that.

In regards to the service manual, I can't seem to be able to find one since the Ninja 400r isn't very common... then again I haven't tried very hard but I'll definitely keep looking. Thanks for that!

I certainly hope the guy from Kawi is just giving me crap... it's not nice knowing that I dropped some good cash on a fuel injected bike that needs to be treated like it has carbs. Good thing is that my mechanic told me that Kawi is willing to swap the ECU to try it out so I'll see if that works out. Hopefully this warranty pulls through... I think I have until the end of the year.

Thanks for all your help so far! I've also heard that a crappy battery could lead to something like this... anyone hear/experience this before?
 
Yes actually. If the voltage goes too low the bike can shut down. The thing is, the tech should have been able to identify that if indeed the battery is a candidate.
 
If you leave the clutch engaged as you brake until the revs drop to normal idle speed, and only then pull in the clutch lever, what happens? (I'm guessing that it will stay running if you do that. This is what you are supposed to do - as opposed to pulling in the clutch with the engine well above idle speed and then coasting.)

It appears that a number of late model fuel injected bikes have had this issue.

I believe it is an ECU programming/calibration issue that is built into the design, and you can possibly do things to cover up the issue but not really fix it, short of having the ECU re-flashed by a third party knowledgeable enough to deal with and fix the issue.

All modern fuel injected engines have a feature called "deceleration fuel cut". If you shut the throttle completely with the revs well above normal idling speed, all fuel delivery is shut off. Aside from saving fuel, it also avoids possibly damaging the catalytic converter, because the tiny amount of air/fuel mixture in the cylinder during deceleration is unlikely to ignite with a spark, but then it will get pumped through to the catalyst, and they are not designed to handle raw air/fuel mixture, that can overheat them.

The issue on the CBR250R happens when the engine comes back out of decel fuel cut. Understand that with a normal port fuel injection engine, not all of the fuel sprayed by the injector goes straight into the cylinder; some of it hits the walls of the intake port and wets them with fuel and that evaporates and goes in during subsequent intake strokes. During coasting with the fuel shut off, all that wall-wetting evaporates. So when the injector comes back on as the revs drop during coastdown, the first shot of fuel should be a slightly greater amount in order to re-wet the port walls. If that isn't done, and whatever fuel gets into the cylinders ends up being too lean to fire, the engine will misfire for the first couple of cycles and if the situation is bad enough, it could stall.

The tipoff is that if you leave it in gear longer - clutch lever out - so that the engine is mechanically driven through the time when the injectors come back on just above idling speed, that will keep it spinning through those first few cycles and then it won't stall.

Why was the manufacturer too stingy with that first shot of fuel ... likely emissions. It's better for emissions if they guess a little on the lean side ... too bad about the driveability issues.

What can you do ...

Check the valve clearances. If they are out of whack it could lead to the engine drawing more air through under some conditions and then going too lean to fire.

New spark plug - and if it specifies iridium, do that, don't cheap out. Reason: better at firing weak or lean mixtures.

Run some injector cleaner through the next couple of tanks of fuel. Reason; if there is slight injector clogging it can lean out the mixture a little, and if it was on the hairy edge, that could make it too lean to fire.

Ride properly ... don't pull in the clutch when stopping until the engine has already dropped to idle speed.
 
Brian, I am someone who oftens pulls the clutch when braking for a smoother faster stop. I find I often don't have enough distance to shift 3-5 gears one by one down to 1st. Sometimes I try doing them which just makes the rpms go higher. Rev limiter is 40 at 1st on my bike so if I am in 2nd at 60 it's already pretty loud. Often I am approaching at 60 or whatever, pull both clutch and brake and release throttle and begin shifting down while coasting. Yes I am a newb but I am not sure what I can do on a low cc to avoid coasting without screaming the engine.
 
Brian, I am someone who oftens pulls the clutch when braking for a smoother faster stop. I find I often don't have enough distance to shift 3-5 gears one by one down to 1st. Sometimes I try doing them which just makes the rpms go higher. Rev limiter is 40 at 1st on my bike so if I am in 2nd at 60 it's already pretty loud. Often I am approaching at 60 or whatever, pull both clutch and brake and release throttle and begin shifting down while coasting. Yes I am a newb but I am not sure what I can do on a low cc to avoid coasting without screaming the engine.

Brake more before downshifting then.
 
Brian, I am someone who oftens pulls the clutch when braking for a smoother faster stop. I find I often don't have enough distance to shift 3-5 gears one by one down to 1st. Sometimes I try doing them which just makes the rpms go higher. Rev limiter is 40 at 1st on my bike so if I am in 2nd at 60 it's already pretty loud. Often I am approaching at 60 or whatever, pull both clutch and brake and release throttle and begin shifting down while coasting. Yes I am a newb but I am not sure what I can do on a low cc to avoid coasting without screaming the engine.

You are trying to downshift too many gears at once and at too high revs. Don't do that.

For normal stopping or slowing down - Just do each downshift one at a time in each gear when the revs drop to something reasonable for the downshift (say 3000 rpm). So say you are in 4th. Slow down, when the revs drop to 3000 then go to 3rd, when the revs again drop to 3000 shift to 2nd. At that point my usual practice is to leave the clutch engaged in 2nd gear until the revs drop close to idle speed, then pull in the clutch and do the downshift to 1st with the clutch held in until the stop, this avoids an often awkward and jerky downshift to 1st while moving. In a normal stop there should be plenty of time to do this. No overrevving by downshifting too many gears at once, and the bike is always in an appropriate gear to resume accelerating should that be necessary, and if your engine has the driveability glitch described in this thread, leaving the clutch engaged until the engine drops to idle speed (in 2nd) keeps the engine spinning through that period when it comes out of deceleration fuel cut.

edit: The only time you might not have time to do this is in an emergency panic stop - but if you are riding properly, that should be a rare event. If and when an emergency panic stop happens, forget about being in the right gear, and whether the engine stalls or not is the least of your worries. Just get it stopped and deal with the aftereffects later.
 
Okay so I totally didn't get emails when this thread got replies... sorry for not responding sooner!

UPDATE: The Kawi rep called me back and said that he thinks that it's a valve lash issue. He opted not to explain details to me (probably because he thinks I'm noob) but that's all he told me. I'm bringing the bike back in for another valve clearance check next week. My mechanic says that they are already to spec when he checked but he'll do it anyway.

Brian P - I usually don't coast to a stop... I usually go down through the gears and then pull in the clutch soon before I get to the line , similar to how you described in your last post. Usually I downshift all the way to 1st... but with this riding technique, the bike still dies or has a decreased idle unless i keep the throttle slightly open at the stop. However, it is also true that I noticed that the bike is more guaranteed to die if I get lazy and pull in the clutch lever early as I coast to the stop. Regarding the injectors and spark plugs, the mechanic already checked those (I watched him do it) and he even replaced the plugs. Nothing changed. Thanks for the suggestions and explanations though! Def learning some new stuff!
 
UPDATE 2: Okay so I brought the bike back a few weeks ago to get the valve clearance adjusted so that the bike runs more rich but still within spec... VOILA! No more stalling at idle... except now she has a very poor throttle response upon start up! I was gonna get the bike adjusted again except I got into a collision. SO, the fate of my bike is in the hands of my insurance company now... but I will ride again!

Just wanted to update just in case anyone ever experiences anything similar to this in the future!
 
Hope your okay and hope the bike is written off 400r is a dog of a bike

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Hope your okay and hope the bike is written off 400r is a dog of a bike

LOL it's not too bad... very comfortable in terms of the seat and the riding position but it's a heavy *** bike, especially compared to the ninja 300. If I got a cash settlement, I honestly wouldn't know what to do with it... I'm under 25 so I'm stuck with either the ninja 300 or CBR 500 but neither of them really interest me. I don't really want to miss out on the riding season either since it essentially just started....
 
It is bad the 300 is faster cuz of the power to weight ratio. 400 is just a 650 with a 400 motor lol. And Yea get the 300 great bike, loads of fun. Oh and get on ur insurance ass keep bugging them all the time it took over two months to get a settlement on my crashed bike years ago but that was with td they suck.

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It is bad the 300 is faster cuz of the power to weight ratio. 400 is just a 650 with a 400 motor lol. And Yea get the 300 great bike, loads of fun. Oh and get on ur insurance ass keep bugging them all the time it took over two months to get a settlement on my crashed bike years ago but that was with td they suck.

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The ninja 400 has a better power to weight ratio. 385:35 = 11 is the 300s and 448:43 = 10.5 -- the smaller the number the more power to weight.

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The ninja 400 has a better power to weight ratio. 385:35 = 11 is the 300s and 448:43 = 10.5 -- the smaller the number the more power to weight.

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Those are Bs manufacturing numbers I've ridden both bikes numerous times and the 300 is quicker not to mention a ton lighter and cheaper. The 400 was a **** up hence they made it for a two or three years

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Those are Bs manufacturing numbers I've ridden both bikes numerous times and the 300 is quicker not to mention a ton lighter and cheaper. The 400 was a **** up hence they made it for a two or three years

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Well when you compare BS manufacturing number to BS manufacturing number the power to weight ratio goes in favour with the 400. saying one bike is quicker when the empirical evidence shows otherwise means you are speaking out of subjectivity.

Also they brought back the 400 for 2012 and 2013 in the U.s with a similar style just different colour scheme. Havent been paying attention if they brought it back for this year.

Just cause they stop making bikes doesnt mean they are objectively bad. Ie: the ninja 500.

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It's a matter of opinion really but having ridden both bikes numerous times, I would be any money the 300 would be faster than 400 on a track. 400 blows balls they only made it for 2 years 500 was great made it for what like 20 years?

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