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Discussion Starter · #1 ·
So my bike is lurching when trying to maintain a speed the rpm bar will climb and fall a bar every other second. Same with the speedo. Any ideas? Is that a misfire or what do you guys think?

Really noticed it after my 1800 mile weekend and the dragon.
Ps... Makes me hate Illinois and it's straight roads lol.

Any advice is appreciated.
 

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I'm sorry but this is a lil off topic... Where did u get those bad ass looking headlights!!!! nd is that with highbeam off or on?.. btw im a noobie with bikes so i dont got any suggestions
 

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How many miles on the bike, when's the last time it was serviced and tuned?

This type of problem can be difficult to diagnose as it can be caused by a number of things- throttle bodies may be out of synch, you might have a problem with your pressure sensor, a leaking vacuum hose, sub throttle sensor or actuator, etc.

By far the easiest way to identify the problem is to have your Kawasaki dealer plug the bike into their diagnostic computer to check for fault codes.

Good luck! Let us know how it goes.

T
 

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Discussion Starter · #4 ·
I've done all the oil changes, fluid checks, brakes myself. I think I'm at 10k-11k miles now. I know valve check isn't till 25k or something. I did notice before tho that on the left side of the tank when facing normally onthe bike seat that one of those hoses on the left side under the tank had a small crack. Is it possible it could of gotten worse and is that a vacuum hose? Didn't seem like a gas line since the petcock is on the right I believe.
 

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EFI bikes don't have a petcock.

If a rubber hose has a cut/crack, replace it. Rubber vacuum hose is super cheap. Might want to find some silicone nipples for the two ports on the throttle bodies where you hook up the gauges to sync them. They're just rubber and rubber just decays after many heat cycles.
 

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Sounds like a misfire - probably a failed coil, or a plug if you're lucky.

It's worth trying to run some injector cleaner through the fuel system as well, but fuel issues tend to be a softer power loss while a more sudden one and equally sudden recovery point to a misfire.

Dead easy to tell which if you're riding the bike, but not so easy in a forum.

There are no vacum hoses to the tank. Fuel is pumped. THere is a fuel line on the right and a vent hose on the left. Damage to that will have no effect on performance. It's there simply to route excess petrol down safely out of the way if you overfill the tank and it overflows a bit when the fuel expands.

Good idea on the fault codes, but as you're not seeing the EFI light and the coils and plugs don't raise fault codes it might not help. I think that there's a coil continuity code, but I've had 2 failed coils and from that and from other people's posts the usual fail doesn't raise a fault code.

Sensors would show a fault code and the power loss would be more consistent - not the erratic behaviour you describe.

Last point - although I've never actually had rubber hose decay, even after 100,000 miles, the nipples on the TBs can be linked by a section of rubber tube, replacing the nipple covers. This gives slightly smoother and more consistent throttle response pulling from low revs and light throttle cruising. Not the source of your problem, but as you'll have to take the tank off to get at the plugs and coils you may as well do that whill you're in there.

Rob
 

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Discussion Starter · #7 ·
Well pulled the tank off this morning. Gonna replace that drain tube that's split with a crack and pulled the air filter... Was black pretty much. Was pretty clean at the start of the season... So I'm hoping that's just the issue, ordered a new one from Indy superbikes since their not far and hope it shows up quickly. Gonna run some fuel injector cleaner thru as well an see how it turns out. Otherwise all tubing and stuff looks just fine visually. Haven't checked the dealership to see if they'll check for fault codes.. I'll do that if this isn't a fix.
 

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While the tank's off, pull the coils and plugs. If a coil has jammed and is hard to remove it will probably have to be replaced. Best to replace the plugs any time the tank and air filter are off simply because they're a PITA to get at .

Rob
 

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Well pulled the tank off this morning. Gonna replace that drain tube that's split with a crack and pulled the air filter... Was black pretty much. Was pretty clean at the start of the season... So I'm hoping that's just the issue, ordered a new one from Indy superbikes since their not far and hope it shows up quickly. Gonna run some fuel injector cleaner thru as well an see how it turns out. Otherwise all tubing and stuff looks just fine visually. Haven't checked the dealership to see if they'll check for fault codes.. I'll do that if this isn't a fix.
It's very unlikely that the problem you are describing is caused by a dirty air filter... Keep going!
 

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I've done all the oil changes, fluid checks, brakes myself. I think I'm at 10k-11k miles now. I know valve check isn't till 25k or something. I did notice before tho that on the left side of the tank when facing normally onthe bike seat that one of those hoses on the left side under the tank had a small crack. Is it possible it could of gotten worse and is that a vacuum hose? Didn't seem like a gas line since the petcock is on the right I believe.
My surging issue started around that mark and was fixed by a new chain
and sprockets.
 

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My surging issue started around that mark and was fixed by a new chain
and sprockets.
Yup. Loose chain or a chain with tight links csn cause jerkiness or a pulling feeling. Get your rear wheel in the air and hand twist each link so see how many tight ones you have.
 

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My surging issue started around that mark and was fixed by a new chain
and sprockets.
Ding ding ding ding ding!!! I would bet money that this is your problem. Pull the front sprocket cover off, get the rear wheel off the ground and rotate the wheel. see if any links bind at the front sprocket.
 

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My surging issue started around that mark and was fixed by a new chain
and sprockets.
This is the problem with trying to diagnose on a forum. You're reading the original post differently to me and it's not impossible that neither of us are reading it right. So we all have very different ideas of what the problem might be.

Rob
 

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This is the problem with trying to diagnose on a forum. You're reading the original post differently to me and it's not impossible that neither of us are reading it right. So we all have very different ideas of what the problem might be.

Rob
Chain wear will appear and start causing surging like described, no question
about it. Everything else is a fault that's not that common, and most people
never had it.

But yeah, impossible to diagnose this way..
 

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But I didn't read the post as surging. I read it as more like misfiring, which is also very common. I think every bike I've owned has suffered a misfire at some point, but very few have had the chain wear to a point where it's caused a problem because regular maintenance prevents that.

Surging from a stretched chain is a regular cyclic thing, wheras a missfire is more haphazard, more immediate and more throttle load dependent.

Maybe the OP could add a bit more?

Rob
 

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Discussion Starter · #16 ·
I'm thinking it's the chain myself now. The only time it's noticeable is on deceleration and trying to hold around 4k. The bike doesn't miss fire(don't believe it to be the case) or seem to be running rich of anything of that sort.

When I returned from my vacation the chain had been pretty loose. It's very possible that it could just be worn from the 11k miles on it now. I'll check for binding and replace the chain and sprocket if so.
 

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11k is usually worn. My last one last 10k. Some people can get more but those are usually the very anal cleaning type. Plus how you ride will affect chain wear.
 

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11k is usually worn. My last one last 10k. Some people can get more but those are usually the very anal cleaning type. Plus how you ride will affect chain wear.
I just replaced my first chain at 20k miles, obsessive with cleaning/chain lube,
very smooth rider. However, like I said, the slight surging started around 11-12k.
 

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Discussion Starter · #19 ·
I Try to be smooth with shifts and acceleration. It's most likely the chain cause I feel a pulse now by the left foot peg when coming to a stop with engine braking. I'll be replacing it soon with new sprockets.

Now what color to get? I love the gold stuff but I don't think it will fit with the black and gray them of the bike.
 

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Discussion Starter · #20 ·
Update: after replacing sprockets and chain... It was the issue. The chain was too tight and loose in areas from stretching and was binding on the front sprocket.

New one works perfect. Bike holds rpm and speed perfectly and doesn't surge. No misfire. :)
 
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