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.
:cheers:
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
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.
Quote from: seth on Sunday, 05 July 2020, 11:05 PM
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.
:cheers:
Quote from: numbskull on Monday, 06 July 2020, 12:48 AM
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 :facepalm:
:cheers:
New chain & sprockets & your problem will be solved i'd say.
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!
BJ, idle is 1100rpm, some even have it at 1200. Put the idle in there somewhere & see how it is.
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.
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.
In an attempt to eliminate those two switches can I unplug them and run a wire across them and see what happens?
Quote from: BJ on Monday, 06 July 2020, 04:28 PM
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
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.
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 . . .
@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 .
.
Quote from: BJ on Monday, 06 July 2020, 04:44 PM
In an attempt to eliminate those two switches can I unplug them and run a wire across them and see what happens?
Ish.
Do that to get the bike to start, but test ride it without them switches connected or bypassed. Just doing the clutch switch is enough as it's inline with the sidestand switch (from memory) so disconnecting one takes both out the circuit.
As someone else said, they don't ride right with the switches bypassed. I did it to mine once & it was thirsty as hell, slow & backfired under power.
I replaced the vacuum lines on mine and that made a huge difference. The lines may look ok but hairline cracks allow false air that upsets the air fuel ratio down low. You wont notice it at high rpm as the amount of fresh vs vac air is much higher, but down low it becomes awful to ride. I replaced the t connectors as well.
I assume you have checked plugs and leads too?
Quote from: seth on Monday, 06 July 2020, 05:21 PM
@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 .
.
Totally agree
@seth, but for purposes of checking whether it makes any difference, bypassing them for a short test run would be OK IMO but totally agree that in the longer run, leaving them bypassed is a no no.
Quote from: gsxbarmy on Monday, 06 July 2020, 06:09 PM
Quote from: seth on Monday, 06 July 2020, 05:21 PM
@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 .
.
Totally agree @seth, but for purposes of checking whether it makes any difference, bypassing them for a short test run would be OK IMO but totally agree that in the longer run, leaving them bypassed is a no no.
Seems to vary on 14s, but mine rode awful with them bypassed so you still think it's faulty.
Quote from: Eric GSX1400K3 on Monday, 06 July 2020, 05:32 PM
I replaced the vacuum lines on mine and that made a huge difference. The lines may look ok but hairline cracks allow false air that upsets the air fuel ratio down low. You wont notice it at high rpm as the amount of fresh vs vac air is much higher, but down low it becomes awful to ride. I replaced the t connectors as well.
I assume you have checked plugs and leads too?
Good call, I had to do my vaccuum lines this year too.
Part of the reason you won't notice it at higher speeds is the ECU doesn't use the MAP sensor (that the vaccuum pipes go to) above a certain rev/throttle opening limit.
Vacuum lines is a good shout to check :cheers:
BJ, what a PIA your bike. So many things replaced, adjusted for no result. I wouldve sold it after all this time trying. Id set idle at 1100 again, reset TPS after that. I know you like a bit of free play at throttle, Ducati sure have lots of that, yours have it built in, why you like it. 14 needs at close to zero, adjust at top, tight as you can get without affecting revs turning bars to each lock. Have a listen to throttle bodies when closing, make sure you can hear it returning to totally closed, a must. Adjust closing cable to get that click,adjust at bar end. If no better, give me a ring, will swap bikes to compare.
Quote from: gsxbarmy on Monday, 06 July 2020, 04:39 PM
Quote from: Eric GSX1400K3 on Monday, 06 July 2020, 05:32 PM
I replaced the vacuum lines on mine and that made a huge difference. The lines may look ok but hairline cracks allow false air that upsets the air fuel ratio down low. You wont notice it at high rpm as the amount of fresh vs vac air is much higher, but down low it becomes awful to ride. I replaced the t connectors as well.
I assume you have checked plugs and leads too?
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.
I can't seem to find a clutch switch. Is it on this section?
https://www.moto-pecas-suz.com/suzuki-motociclos/1400-MOTO/GSX/2002/GSX1400K2-E2-/ELECTRICO/FEIXE-ELECTRICO-GSX1400K2-UK2-K3-UK3-/7/3099857/E/1355
Quote from: froudy on Monday, 06 July 2020, 04:55 PM
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.
You're right! it is insane. It may have the advantage of being very quik through the gears. Good for drag racing I suppose.
Quote from: seth on Monday, 06 July 2020, 06:56 PM
Vacuum lines is a good shout to check :cheers:
I don't actually know what Vacuum lines are for now. But would they be here?
https://www.moto-pecas-suz.com/suzuki-motociclos/1400-MOTO/GSX/2002/GSX1400K2-E2-/MOTOR-TRANSMISSAO/MANGUEIRA--JUNTA-DO-CORPO-DO-ACELERADOR-MODELE-K2-/7/3099282/M/1355
Quote from: Eric GSX1400K3 on Monday, 06 July 2020, 05:32 PM
I assume you have checked plugs and leads too?
New plugs were fitted. How does one checks the leads? visual inspection? look for cracks?
Guys this all makes sence, since we are talking about an 18 year old bike. which has everything still stock by the looks of it, hoses and lines.
One thing I am really happy with is the fact that not a single drop of oil comes out the block, engine is immaculate. Only oil I can find has come from chain. Most people just add oil to the chain. Years of this conduct will accumulate oil on front sprocket cover.
I have a DID and AFAM sprockets to install. I was only to fit it in the winter but, since it maybe be causing trouble, I will change them ASAP.
:cheers:
The clutch switch isn't on that link, it's fitted under the lever pivot.
The vacuum pipes are the thin ones off the top of the throttle bodies. 3.8mm from memory.
There are five of them, four join together & go to the MAP sensor in the top frame rail & one goes to the PAIRs valve.
:onya: :onya:
I don't actually know what Vacuum lines are for now. But would they be here?
https://www.moto-pecas-suz.com/suzuki-motociclos/1400-MOTO/GSX/2002/GSX1400K2-E2-/MOTOR-TRANSMISSAO/MANGUEIRA--JUNTA-DO-CORPO-DO-ACELERADOR-MODELE-K2-/7/3099282/M/1355
Yes, item 10-15in the diagram are the vacuum lines. Buy a roll of engine vac hose and a box of fittings off ebay, should cost about AUD40. Can get cheaper but you want quality hose that doesnt dissolve at the first hint of fuel.
Quote from: Eric GSX1400K3 on Monday, 06 July 2020, 05:32 PM
I assume you have checked plugs and leads too?
New plugs were fitted. How does one checks the leads? visual inspection? look for cracks?
Yes, check the lines for cracks and that the ends are correctly inserted into the plug caps.
Guys this all makes sence, since we are talking about an 18 year old bike. which has everything still stock by the looks of it, hoses and lines.
One thing I am really happy with is the fact that not a single drop of oil comes out the block, engine is immaculate. Only oil I can find has come from chain. Most people just add oil to the chain. Years of this conduct will accumulate oil on front sprocket cover.
I have a DID and AFAM sprockets to install. I was only to fit it in the winter but, since it maybe be causing trouble, I will change them ASAP.
:cheers:
[/quote]
haven`t done this myself, but i like the concept
https://www.youtube.com/watch?v=8k1B_lTr-pA
So, after a suggestion on this forum to run my bike with the standard exhaust I got on Facebook "Australia GSX1400" yesterday requesting a left side "Bazooka".
A very kind member gave me his for free so I donated a carton of beer.
I put the pipe on this afternoon and did about 10 kms with the main aim to see how it reacted going on and off the throttle.
I ran the bike down to idle speed, 1100, several times and powered off again with NO jerky what so ever.
A HUGE improvement over the Yoshimura slip on.
The BIG OEM Bazooka is a LOT to love but if it solves my throttle issues I can live with it.
Besides of late I have put OEM exhausts back on my 01 speed triple and my MT01 and maybe now my 14.
I'm just getting too old for loud.
I'll report back after a week of so. Haven't hit the roundabouts yet so that should b a good indicator.
BJ, if back pressure works, BPE in Bris can make you up any can you want. I mean a better looker with back pressure. they seem to aim to please. I spoke to them about different for mine. would like something similar to MT09, small and tucked in. Reckons he can do. Just a thought.
@KiwiCol Well done mate, the big Bazooka, not a bit of wonder I have never had any issues with my bike. Its standard only changed oil and filters and it goes as fast or faster than the one's with mod's on them :stir:
Quote from: grog on Thursday, 09 July 2020, 07:23 PM
BJ, if back pressure works, BPE in Bris can make you up any can you want. I mean a better looker with back pressure. they seem to aim to please. I spoke to them about different for mine. would like something similar to MT09, small and tucked in. Reckons he can do. Just a thought.
BPE ????? :whatever:
MEP, what i meant, had just been thinking BPE on another subject. Yeah i know, old frogwits should be banned. Thanks GSX
Had a similar issue, felt like it was very slightly hunting around 1500-1700, went for a good ride to get it nice and warm, set tick over at 1100 and re-adjusted TPS, adjusted throttle cables so there was minimal slack and problem now solved :onya: