Jerking fixed switching front sprocket

[Jambo]

Hey all.
Dropped my 14 at the shop because it was misfiring and previous owner advised to, aftermarket mufflers were installed and never retuned.
When I piked up the bike, I did not misfire anymore and power was now constant. I was very pleased.
But further down testing, I noticed that, at first in sixth gear, while coasting, throttle off, speed and rev coming down, at 2000rpm sharp, bike started to jerk violently in some cases. I went back and exposed my findings at the shop and what the head mechanic reply was that is normal, too much torque. I still insisted he had a look and he said ok leave the bike.
I picked up the bike yesterday and what the mechanic did to resolve the issue was fitting a 16 front sprocket. It actually works, not perfect but much better, I still feel the engine jerking but very little. It works for me but I still don't understand why the jerking is normal.
Now I realy need a speedohealer, I have a clue of the real speed now, I have used the calculater provided on this forum, which is awesome! thanks for the creator.
The question is. Is it normal this jerk? I have seen on youtube people trying to get rid of jerkiness on their bike using a computer. I am not still convinced it is normal.

[seth]

It's not normal the gsx1400 should be nice and smooth running .
Changing the sprocket hides the problem not fixed it.
Something else must be causing the poor running .
I'd go for to low a tick over it should be 1100rpm and you might also want to set up the tps and stps then have the throttle bodies balanced .
Good luck

[numbskull]

I went through all of the various adjustments. What made the biggest difference was replacing the chain. It had some stiff links which made it very jerky at low revs and difficult to ride smoothly at low speeds.

[Jambo]

It's not normal the gsx1400 should be nice and smooth running .
Changing the sprocket hides the problem not fixed it.
Something else must be causing the poor running .
I'd go for to low a tick over it should be 1100rpm and you might also want to set up the tps and stps then have the throttle bodies balanced .
Good luck

Thing is, word on the streets is the shop should be good. Bloke over there is or was a professional racer.
Even worst, bike did not do that in the first place. It misfired, it was a diferent problem, which he fixed and lead to this jerkiness.
As you said and correctly, it hides the jerk.
By the way, I went for a ride today and I rather have the 18 sprocket, because riding at same speeds engine revs higher and if the sprocket calculator is correct, in 6th gear with 190/55@6250rpm is 121kph, speedo marked 200kph which is insane in my opinion.
Shop intalled by my request, the GIpro  ATRE G2. That works fine.

[Jambo]

I went through all of the various adjustments. What made the biggest difference was replacing the chain. It had some stiff links which made it very jerky at low revs and difficult to ride smoothly at low speeds.

Chain on the bike has some corrosion. It not that bad, so I thought 

[Sweaty]

New chain & sprockets & your problem will be solved i'd say.

[BJ]

I put on new chain and sprockets. I have replaced plugs, air filter, vac hoses, pairs removal, set TPS exact and STPS exact, bought quality vac gauges and have the bike running perfect except for jerky down low. Did the shims and they are spot on. Swing arm bearing two months ago. Aghhhhhhhhhhh!!
Even ran it today at 800 idle which smoothed it a little but it stalled 6 times in 10 minutes so back up to about 950.
My 14 is my town bike and it's driving me crazy.
Next on my list is injector clean even though shop said they did it 6 months ago.
I'm also going to run it a little without the air filter and see if there is an change as I had the air filter out a few months ago and it ran much better. At that time I was running the filter with the entry tube which runs half way into the filter. It was running like shit and changed to OEM air filter and instant improvement.
Am also going to look at my throttle cables as mine are not that tight and word seems to be that they should be. I would like to know if the throttle cables are tightened down where the injectors are, can you still have a little free play on the actual hand-throttle cause I always like that.
If anyone had solved this jerkiness PLEASE do tell. Good luck to everyone!

[KiwiCol]

BJ, idle is 1100rpm, some even have it at 1200.  Put the idle in there somewhere & see how it is.

[BJ]

Had it at 1100 for months.
But I'll "try anything" at least once so I'll run it 1200 for a while and see what gives.
As I only ride it round town I have a feeling I'll be hauling the clutch in non stop in slowing traffic, small roundabouts etc.
Forgot to say, also put on new sidestand switch and clutch switch.

[gsxbarmy]

Not on my 14, but a few years ago on my Honda VTR, it started to jerk all over the place. By process of elimination, and after checking (bypassing) the connections for the kill switch and clutch switch, it turned out to be the sidestand switch - but not the switch itself! The tab on the sidestand has worn allowing the switch itself to open/close just a tad on acceleration causing the hesitation.

Your problem may be electrical, on the 14, the clutch switch (as we all know) can cause issues, for the cost, may be worth replacing that? Alternatively, if you take your one off, there is a small hole underneath, spray some contact cleaner in there.

[BJ]

In an attempt to eliminate those two switches can I unplug them and run a wire across them and see what happens?

[steve porter]

I put on new chain and sprockets. I have replaced plugs, air filter, vac hoses, pairs removal, set TPS exact and STPS exact, bought quality vac gauges and have the bike running perfect except for jerky down low. Did the shims and they are spot on. Swing arm bearing two months ago. Aghhhhhhhhhhh!!
Even ran it today at 800 idle which smoothed it a little but it stalled 6 times in 10 minutes so back up to about 950.
My 14 is my town bike and it's driving me crazy.
Next on my list is injector clean even though shop said they did it 6 months ago.
I'm also going to run it a little without the air filter and see if there is an change as I had the air filter out a few months ago and it ran much better. At that time I was running the filter with the entry tube which runs half way into the filter. It was running like shit and changed to OEM air filter and instant improvement.
Am also going to look at my throttle cables as mine are not that tight and word seems to be that they should be. I would like to know if the throttle cables are tightened down where the injectors are, can you still have a little free play on the actual hand-throttle cause I always like that.
If anyone had solved this jerkiness PLEASE do tell. Good luck to everyone!

if your baffle is out, try putting it back in, mine smoothed out a lot with a bit of back pressure

[froudy]

Dropping to a 16t front sprocket is going to knock around 20mph off top speed. You'll struggle to hit 120. Not my idea of a "Fix" to the problem.

[KiwiCol]

BJ, bung the bazooka back on & have a try with that.    God, imagine if that worked, having to ride with 'that' on.    Be quiet Irish . . .

[seth]

@BJ
Don't ride with the clutch/ sidestand switches bypassed as the ecu runs a different map and may make things worse in the way the bike runs .
Check the switches and keep them in the circuits required .
.