GSX1400 Owners .org

Technically Speaking => General Technical discussion => Topic started by: Mike40 on Friday, 13 July 2018, 05:11 AM

Title: Jerky on closed Throttle
Post by: Mike40 on Friday, 13 July 2018, 05:11 AM
Rode my new purchase back from Cornwall on Saturday and I have fallen in love with my GSX1400....... :smitten:

However I am not sure if she is running right or if this is just what all these do? When approaching a junction or traffic with a closed throttle it is really jerky, sort of surging on and off and is really difficult to ride smoothly in slow traffic where you are opening and then closing the throttle at slow speed.

There is no misfiring and is smooth on any throttle opening, just not closed??

Any suggestions as it is a long ride back to the dealer in Cornwall......... :undecided:
Title: Re: Jerky on closed Throttle
Post by: Mister Fishfinger on Friday, 13 July 2018, 05:32 AM
Mine was a bit like that on the first trip home. I bought it privately and it turned out that the previous owner had a fairly lax attitude to maintenance, so the chain was really slack. Tightening that up improved things no end. Worth a quick look (although to be fair a dealer should have sorted all that).
Title: Re: Jerky on closed Throttle
Post by: Kiwifruit on Friday, 13 July 2018, 05:37 AM
Throttle cable adjustment can make quite a difference to how they ride at low speed.
Enjoy your new bike  :onya:
Title: Re: Jerky on closed Throttle
Post by: northern on Friday, 13 July 2018, 05:43 AM
Also - don't forget 1402cc is a lot, and torque starts almost from idle. So bike react on even slight change of throttle. Especially on lover gears.
Title: Re: Jerky on closed Throttle
Post by: Hooli on Friday, 13 July 2018, 06:14 AM
It'll be chain slack, throttle cable slack, TPS adjustment or dirty plugs.
Title: Re: Jerky on closed Throttle
Post by: Mister Fishfinger on Friday, 13 July 2018, 07:47 AM
Also the PAIRS system is reputed to make it a bit jerky at small throttle openings, especially with aftermarket exhausts. Opinions vary on whether disabling it makes any difference. I haven't touched mine because I like the burbling sound that it makes. Childish I know, but true.
Title: Re: Jerky on closed Throttle
Post by: froudy on Friday, 13 July 2018, 07:57 AM
PAIR removed on mine. Beowulf slightly shortened end can. 5 Degree ignition advance by slotting backplate...Mine can be jerky at low speeds with small throttle opening..I've just got used to it over time.
Title: Re: Jerky on closed Throttle
Post by: northern on Friday, 13 July 2018, 08:40 AM
same here - used.
And learn to play with clutch more then on 600cc bike :)
Title: Re: Jerky on closed Throttle
Post by: KiwiCol on Friday, 13 July 2018, 10:20 AM
Hi Mike40 & welcome along.  As the guys have said above, it'll be nothing serious, just a wee bit of tweaking (not twerking) required.
Title: Re: Jerky on closed Throttle
Post by: grog on Friday, 13 July 2018, 07:14 PM
have written to many new owners how to make 14 perfect. maybe we need a list/instruction sheet written up. im not clever enough to write it but know what are the adjustments required. sort of a bike intro , things you must do. if anyone wants, ill list it up for someone to make it a sticky. just want them running perfectly, makes everyone happy. small changes , but great results. mine was supposedly all serviced/set up by dealer when i got it. wrong. so many things wrong. an intro sheet i think a great idea. just trying to help.
Title: Re: Jerky on closed Throttle
Post by: KiwiCol on Friday, 13 July 2018, 07:22 PM
That's a good idea Grog.  Yep, all the little things to 'fine tune' & 'get it running right'   Sounds like it's got Sir David Barmy written all over it . . .
Title: Re: Jerky on closed Throttle
Post by: grog on Friday, 13 July 2018, 07:30 PM
thanks Col. ill write up reqs if someone, Barmy, wants to make it make sense. mine as smooth as a cafe latte, nothing to do with clutch or engine size. they just need a few tweeks. smooth as a Kilcenny from a cold can, much better description.  :happy1:
Title: Re: Jerky on closed Throttle
Post by: KiwiCol on Friday, 13 July 2018, 07:40 PM
Wot if ya don't like dark beers though?
Title: Re: Jerky on closed Throttle
Post by: Monarchjock on Friday, 13 July 2018, 11:20 PM
Just needs a Barmy write up with links to Barmy's other writeups. Simples. :imrgreen:


Quote from: KiwiCol on Friday, 13 July  2018, 07:40 PM
Wot if ya don't like dark beers though?

Philistine.  :facepalm:
Title: Re: Jerky on closed Throttle
Post by: KiwiCol on Saturday, 14 July 2018, 02:59 AM
Quote from: Monarchjock on Friday, 13 July  2018, 11:20 PM
Just needs a Barmy write up with links to Barmy's other writeups. Simples. :imrgreen:


Quote from: KiwiCol on Friday, 13 July  2018, 07:40 PM
Wot if ya don't like dark beers though?

Philistine.  :facepalm:
Guilty your honour. :whatever:
Title: Re: Jerky on closed Throttle
Post by: gsxbarmy on Saturday, 14 July 2018, 08:06 AM
Nice idea Grog, I like it.

If you want to write up/outline the processes/checks that you have in mind (and perhaps pm it to me), then I'm happy to sort it and add any links etc to stickys so we can add it up.

@grog
Title: Re: Jerky on closed Throttle
Post by: Hooli on Saturday, 14 July 2018, 03:40 PM
I've just thought of another - iridium plugs. They are shite & only do about 10k miles before needing cleaning regularly, I'm swapping mine back to proper plugs soon to cure a whole host of slow running issues that go away for 300miles if I clean the plugs.
Title: Re: Jerky on closed Throttle
Post by: Aldi on Saturday, 14 July 2018, 05:40 PM
Great idea grog, as a new owner I'd appreciate something like this, especially with a misfiring engine and slightly erratic idle on my bike.

Al
Title: Re: Jerky on closed Throttle
Post by: froudy on Saturday, 14 July 2018, 06:02 PM
Quote from: Hooli on Saturday, 14 July  2018, 03:40 PM
I've just thought of another - iridium plugs. They are shite & only do about 10k miles before needing cleaning regularly, I'm swapping mine back to proper plugs soon to cure a whole host of slow running issues that go away for 300miles if I clean the plugs.

I never had any running issues when I had Iridium plugs fitted. They only caused me problems when I came to change them..They hadn't been touched for 25k miles and were very tight and rusted when I finally decided it was time to change them!
I'm now back on standard NGK plugs to try them.
Title: Re: Jerky on closed Throttle
Post by: grog on Saturday, 14 July 2018, 07:02 PM
Hooli, iridium not your prob. they work fine for a long time. mine at 40 th ks, most cars at work with them 100th. something else is your prob.
Title: Re: Jerky on closed Throttle
Post by: Hooli on Monday, 16 July 2018, 07:05 AM
I'm sure it's the plugs as I got to 100k with just two sets of normal plugs. I'm going to put proper plugs back in when I get chance & once it cures the fault I'll let you know you're wrong.
Title: Re: Jerky on closed Throttle
Post by: grog on Monday, 16 July 2018, 07:45 AM
If im wrong, thatll be number 4 million and something in my life. My wife would say 8 million.   :cheesy:
Title: Re: Jerky on closed Throttle
Post by: KiwiCol on Monday, 16 July 2018, 10:15 AM
Quote from: grog on Monday, 16 July  2018, 07:45 AM
If im wrong, thatll be number 4 million and something in my life. My wife would say 8 million.   :cheesy:
Hmmm, my Mrs could be your wifes twin Grog.