Jerking During Acceleration

[josh smith]

Hey guys I have a 2003 Hayabusa with 20,700 miles on it. Im having a really Bad jerking problem during acceleration. Bike has new chain spocket(frontandback) and spark plugs. I have tried putting sea foam in the tank that still dnt help. Its doing it during take off and acceleration in any gear.

 

[chrisjp]

check fuel pressure... if fuel filter is starting to get clogged this can happen..

 

[Lucid]

Could be electrical. The Gen I charging system has a lot of issues. Might look at battery or stator. I know my bike jerked a lot when I had electrical issues.

 

[jch364]

could it be slipping a gear? Not if its doing it through all the gears of course. just wondering. my 1st and 2nd slipped and jerked when it did thats why I mention that.

 

[twotonevert]

Start with the simple stuff first, all good suggestions above. Also check to make sure the tip over switch is not loose. I have seen this very issue because of it.

 

[josh smith]

ok thanks guy I will be taking the tank off today to check fuel pump and filter!!!

 

[Cantab]

TPS way out ?

 

[Dontae]

Hey guys I have a 2003 Hayabusa with 20,700 miles on it. Im having a really Bad jerking problem during acceleration. Bike has new chain spocket(frontandback) and spark plugs. I have tried putting sea foam in the tank that still dnt help. Its doing it during take off and acceleration in any gear.

 

[Dontae]

Did you ever find out what it was?

 

[rubbersidedown]

Did you ever find out what it was?

Well lets hope so,that was 4 years ago,and the OP has not been back since.

to the Org. There's is a wealth of info here and great people.
What do you ride?
Rubb.

 

[Dontae]

04 busa

 

[Berlin Germany]

@Dontae

read the op´s start post

(...)Bike has new chain spocket(frontandback) and spark plugs. (...). Its doing it during take off and acceleration in any gear.

seemingly he didn´t remove the chain but only the sprockets - what would have been a damn nonsense.

usually one write "one got a new chain set" , what means that all 3 parts are removed, front & rear sprocket AND the chain.

i guess / suppose his chain was to old, was "bitchy" greased / maintained and got different / uneven lengths between the chain links plus "hard" links.
another possibility is that he installed the chain-slack too small respectively the chain tension to high
what also lengths the chain links uneven.
both of these lead to "weird" behavior of a bike

__________________________________________________________​

my dozens of experiances are :
- use an automatic, most simple chain oiler like the pure mechanical "Scott-Oiler V-System" (driven by vaccum taken from 1 of the throttle/intake manifolds), what i recommend and already built in 3 or 4 dozen times with very best results.
- in principle : in best case an oiler saves the chain´s and rear sprocket´s life up to ca. 55 000 - 60 000 miles
- when using an oiler - only - the front sprocket "suffers" and needs to be removed every ca. 22-25 000 miles,
because its teeth bend backwards by the motor´s torque what you can hear while pushing the bike backwards by a "klack klack klack -..." sound / noise coming outa the sprocket cover.

and this behavior applies to all bikes regardless of the engine size.

and yes - there will be others who will say its a sign of stupidness only to change the front sprocket,
but MY (and other´s) experiance told me (them),
that the rear sprocket don´t get any shark teeth til 2nd change of the front sprocket.
i say it again - only the front sprocket suffers but the chain and rear sprocket are fine (if maintained by an oiler)

__________________________________________________________​

and

you can "kill" a brand new chain at first very 1 mile when accelerating and same time crossing a little deeper pothole and the slack of chain was too small.

thatby you directly get uneven link lengths and the chain is done immediately.
the 1st 50-100 miles the chain has, so to say, to be retracted.

 

[BlueBacon]

I have a similar issue and bumped another old post with what's listed below. I know it is not the chain for me.

2003 stock motor/sprockets. Sprockets, clutch plates, and fluids all less than 2 years old. Chain has appropriate slack, oil, and no bad links or noises. 91 pump gas + various fuel/injector cleaners for the last 3 tanks.
I hold 2nd gear at 5k RPM, raise it to 9K quickly, but keeping the front wheel down. Feels like the whole bike stops for .002 seconds somewhere round 6-7k RPM, but then continues without an issue...scary jerk/shudder for that tiny moment though

 

[rubbersidedown]

I have a similar issue and bumped another old post with what's listed below. I know it is not the chain for me.

2003 stock motor/sprockets. Sprockets, clutch plates, and fluids all less than 2 years old. Chain has appropriate slack, oil, and no bad links or noises. 91 pump gas + various fuel/injector cleaners for the last 3 tanks.
I hold 2nd gear at 5k RPM, raise it to 9K quickly, but keeping the front wheel down. Feels like the whole bike stops for .002 seconds somewhere round 6-7k RPM, but then continues without an issue...scary jerk/shudder for that tiny moment though

Each and everytime at 6-7k? Or is it sporadic? 17 year old bike. Is it fairly new to you? How much sitting did it do? If it does it every time,there's a better chance for a correct diagnosis. You've used 3 tanks of injector cleaner,has it improved? You mentioned clutch and final drive. Do the RPM's climb without an' increase in speed? or does the motor cough (hesitate) for a second?
Rubb.

 

[BlueBacon]

Each and everytime at 6-7k? Or is it sporadic? 17 year old bike. Is it fairly new to you? How much sitting did it do? If it does it every time,there's a better chance for a correct diagnosis. You've used 3 tanks of injector cleaner,has it improved? You mentioned clutch and final drive. Do the RPM's climb without an' increase in speed? or does the motor cough (hesitate) for a second?
Rubb.

I've had her for 3-ish years, but rarely ever take her above 6k. Decided to pull on the interstate and see how 2nd gear felt all the way to the speed limit, but then felt that sudden jerk and about pissed myself.
I have since tried it 2 additional times (3 total) and it is the same each time...very brief, sudden jerk for .02 seconds and back to normal. Not rich enough to risk a ticket testing in any other gear

No improvement with the fuel cleaners, tank looks immaculate still. It feels like a mechanical issue.
RPMs do not climb like a slipped clutch and you don't hear engine rev. I twist the throttle, RPM and speed rise, bike jerks like the chain missed one tooth at a high RPM, and continues without a hitch.
My guess would be the transmission clunking out, but I figured that would be more likely if I was dumping the throttle...this is a gradual increase in power, about as fast as doing a dyno pull. Only other thought was the injectors failing for that split second...

 

[rubbersidedown]

I would test it a few ways. The first (ticket-less approach) would be to just have the bike sit there in neutral climb to 5 grand like you did on the road and snap the throttle up to 8 or 9k. You could also do it slowly. Just gradually increase RPM's and see/hear how it does. I'd start there. The test also takes the running gear outa the equation (clutch,trans,etc).
I'd start there. If I couldn't figure it out,I'd be booking an' appointment at a shop that has a dyno.
Rubb.

 

[kml]

Jerking while accelerating?!

I don't know, but if it was me,

I'd keep both hands on the handlebars.

cheers
ken

 

[Sandow]

Jerking while accelerating?!

I don't know, but if it was me,

I'd keep both hands on the handlebars.

cheers
ken

My thought....but I kept it to myself...