tonytooth
Zone Head
Posts: 647
|
posted September 14, 2006 06:13 AM
 Edited By: tonytooth on 14 Sep 2006 09:11
Exhaust popping on decel? I may have the answer.
First off I need to say I already have the Muzzy block off plates installed and they did not prevent this like a lot of people cliamed it would. I had a custom map done yesterday. The guy who tuned it noticed the popping on deceleration. He noticed that from 6500rpm-3500rpm and 0-4% throttle he could add more fuel but it did nothing. He called me to explain he thought it was a bad pc and to hang tight until he heard back from power commander. He called back after speaking with them and they explained it was infact the motorcycle and not the pc. They claim it's a zx14 issue and not a pc issue. The zx14 stock ecu does not offer fuel in this range so you can not raise the % to prevent popping. They all do this and they don't know why. This sounds logical considering many of us have installed block off plates and nothing changed. It can't be corrected with a pc either so enjoy it. I don't mind it, I think it sounds tough. Smokinzx14 loves it because he gets to shoot a flame in the face of the person he beats when he is racing. The only problem I have is, that person is usually me ;0).
____________
MySpace
   
|
smokinZX14
Needs a life
Posts: 10197
|
posted September 14, 2006 06:28 AM
Not me ..  I would never do that to another zx14 , only Busas ...lol...
____________
Smokin Performance Cycles..
Tampa Bay , FL .. Brocks Performance Dealer ..
Gen 2 ZX14R Best ET 8.43 , Best MPH 164.95
|
Stalwart
Needs a job
Posts: 3360
|
posted September 14, 2006 07:10 AM
Many new vehicles schedule NO FUEL on a closed throttle when the engine is much above idle. You don't need fuel for engine braking and it is better for fuel economy and emissions.
____________
Stuart
________________________________
Ridin' the Trump train.
|
TeamSpeed
Expert Class
Posts: 449
|
posted September 14, 2006 07:15 AM
I would not be surprised if at 0% throttle, the bike is still being provided fuel. Vehicles have their idle speed controlled electronically, the bike does not, you can adjust the idle speed to be anything you want with the little adjuster sitting by your left foot.
|
tonytooth
Zone Head
Posts: 647
|
posted September 14, 2006 07:24 AM
Edited By: tonytooth on 14 Sep 2006 09:08
The stock ecu/map is not suplplying fuel there so when you go to give it throttle again and you are in the range of power, it could feel jerky with the system coming back on. Very strange.
____________
MySpace
|
Stalwart
Needs a job
Posts: 3360
|
posted September 14, 2006 07:44 AM
quote:
I would not be surprised if at 0% throttle, the bike is still being provided fuel. Vehicles have their idle speed controlled electronically, the bike does not, you can adjust the idle speed to be anything you want with the little adjuster sitting by your left foot.
The "little adjuster" only changes the position of the throttle valves. The ECU decides if fuel is warranted and as I stated there is no need for fuel during ZERO throttle deceleration until a near idle rpm condition exists. Fuel can be reinstated with virtually NO LAG as we are talking about electronic engine management, not a mechanical system (OK, the injectors are electro-mechanical but still VERY fast).
____________
Stuart
________________________________
Ridin' the Trump train.
|
tonytooth
Zone Head
Posts: 647
|
posted September 14, 2006 08:13 AM
Edited By: tonytooth on 14 Sep 2006 09:14
He claims he was adding 30 and 40% more fuel in this range and nothing was happening. He was chasing the popping trying to get rid of it but the stock ecu does not provide fuel there so doing a 40% increase to zero fuel still gives you zero. That's why the bike still pops. Power Commander confirmed this about the ZX14.
|
iflyphi
Zone Head
Posts: 542
|
posted September 14, 2006 08:22 AM
I have the Brock Sidewinder, and Brock's custom map, and get no popping on decel. Not even one pop. When I had the Muzzy 4 into 1, with a custom map, it would pop once on decel. I have the air valve blocked also. Go figure.
|
Stalwart
Needs a job
Posts: 3360
|
posted September 14, 2006 08:44 AM
quote:
I have the Brock Sidewinder, and Brock's custom map, and get no popping on decel. Not even one pop. When I had the Muzzy 4 into 1, with a custom map, it would pop once on decel. I have the air valve blocked also. Go figure.
Sure, as you back off the throttle, the ECU cuts off fuel and you get a momentary lean condition causing the "pop" and then continues with no fuel until the throttle is opened or the engine approaches idle rpm (the Kawasaki programming sets this RPM) and then fuel is re-introduced. Remember lean A/F ratios burn slower causing the mixture to still be burning as the exhaust valve opens or even in certain cases, the A/F ratio is such that the spark plug is unable to ignite the mixture but it does ignite in the hot exhaust pipe.
____________
Stuart
________________________________
Ridin' the Trump train.
|
iflyphi
Zone Head
Posts: 542
|
posted September 14, 2006 09:54 AM
Huh?? What I was saying is that might does not backfire anymore, at all. I'm trying to figure out why, so that it could help others. With the Muzzy it would pop once or twice on decel, but now, nothing.
|
Stalwart
Needs a job
Posts: 3360
|
posted September 14, 2006 10:09 AM
quote:
Huh?? What I was saying is that might does not backfire anymore, at all.
HUH? Fine, so Brock has managed to get the A/F ratio such that there is no lean ratio, that can't be spark ignited, that enters the pipe on the transition to the "no fuel" part of the map. 
____________
Stuart
________________________________
Ridin' the Trump train.
|
tonytooth
Zone Head
Posts: 647
|
posted September 14, 2006 11:15 AM
quote:
HUH? Fine, so Brock has managed to get the A/F ratio such that there is no lean ratio, that can't be spark ignited, that enters the pipe on the transition to the "no fuel" part of the map.
That sounds logical and possible (good job Brock) but it doesn't explain why there are map numbers in places that no fuel is offered. They do nothing so why are they there?
|
Stalwart
Needs a job
Posts: 3360
|
posted September 14, 2006 11:34 AM
OK, from my experience with automotive EFI systems, closing the throttle doesn't give an immediate cessation of fuel delivery on deceleration. There is a lag built in and all I can figure is those numbers cover the transient time between throttle closing and fuel cutoff. I never made the statement that the 14 had this fuel cutoff, I stated that it could and that it works just fine above idle if certain conditions are met.
I wouldn't expect to see fuel cutoff on any column except the first one ("0") anyway.
____________
Stuart
________________________________
Ridin' the Trump train.
|
ninja14
Pro
Posts: 1136
|
posted September 14, 2006 12:09 PM
I like the pop...........can use it kinda like a horn - they hear me, but since it is not actually the horn it doesn't seem rude :-)
____________
2006 Turbo ZX-14.
2005 V-max 20th Anniv.
|
tonytooth
Zone Head
Posts: 647
|
posted September 14, 2006 12:29 PM
quote:
I like the pop...........can use it kinda like a horn - they hear me, but since it is not actually the horn it doesn't seem rude :-)
Me too, I used to hate it but I have grown to love it. It sounds agressive.
|
ninja14
Pro
Posts: 1136
|
posted September 14, 2006 01:05 PM
Edited By: ninja14 on 14 Sep 2006 14:12
No pop, but :
.....turn up the sound.
____________
2006 Turbo ZX-14.
2005 V-max 20th Anniv.
|
fastestbusaaround
Needs a life
I eat Fish...
Posts: 7889
|
posted September 14, 2006 01:26 PM
quote:
quote:
HUH? Fine, so Brock has managed to get the A/F ratio such that there is no lean ratio, that can't be spark ignited, that enters the pipe on the transition to the "no fuel" part of the map.
That sounds logical and possible (good job Brock) but it doesn't explain why there are map numbers in places that no fuel is offered. They do nothing so why are they there?
Thats the DJ Tuning link software that automatically populates those values you see...they generally don't insert those values manually.
____________
FYYFF!!!
|
INTIMIDA2OR
Needs a life
RED rider!
Posts: 13081
|
posted September 14, 2006 01:30 PM
Mine popped when i 1st got my Bruce slip-ons , but after tweaking my fuel optimizer almost 0 popping .
The only time it pops is if i don't close the throttle all the way on decel , but when totally closed on decel my motor is smooth and quiet !
____________
'06 Passion Red ZX-14
*Lee*
|
RICH CRAFT 1
Zone Head
Posts: 681
|
posted September 14, 2006 01:31 PM
So heres my theory. New cars and I believe the 14 carry a dual map one for gas mileage the other for performance. If you whack the throttle a couple of times you ll notice that the back fireing increases. This is caused by un burnt gas when you let off the throttle it shuts the oxygen off but the fuel continues through the pipe fresh air leaking around the slip on joint can ignite the un burnt gas. The next time you ride your 14 notice after you hard excellerat and let off if the popping is more. Maybe sealing the joints where they slip together might help.
____________
Red 06 ZX14 RR
|
tonytooth
Zone Head
Posts: 647
|
posted September 14, 2006 01:51 PM
quote:
Thats the DJ Tuning link software that automatically populates those values you see...they generally don't insert those values manually.
Thank you, that explains more.
|
fastestbusaaround
Needs a life
I eat Fish...
Posts: 7889
|
posted September 14, 2006 03:10 PM
quote:
So heres my theory. New cars and I believe the 14 carry a dual map one for gas mileage the other for performance. If you whack the throttle a couple of times you ll notice that the back fireing increases. This is caused by un burnt gas when you let off the throttle it shuts the oxygen off but the fuel continues through the pipe fresh air leaking around the slip on joint can ignite the un burnt gas. The next time you ride your 14 notice after you hard excellerat and let off if the popping is more. Maybe sealing the joints where they slip together might help.
...not sure there's any real basis for that theory...sounds good though!:P
____________
FYYFF!!!
|
chez
Expert Class
Posts: 134
|
posted September 14, 2006 04:31 PM
I have Ti Force slip ons on my zx14. I have the flies out and the KLEEN air system blocked off. It used to pop with closed throttle before I blocked off the KLEEN system from Air Box but know even with closed throttle coasting down a long hill no popping at all. The lag is gone at 3000rpm and combined with 16 tooth front and 43 rear the thing launches itself. The throttle is very sensitive but I am used to this now and I don't ride in traffic so no problems.
____________
Chez
|
suicycle
Expert Class
Posts: 136
|
posted September 14, 2006 09:31 PM
mine pops on decel whenever the motor is has been reved above 4500 rpm or so and then closed. It will pop at exactly 3600 rpm every time on the decel. Brocks gen 3, TRE, and pc iii with matching Brocks map. Kleen valve plugged off.
|
fastestbusaaround
Needs a life
I eat Fish...
Posts: 7889
|
posted September 15, 2006 12:45 AM
Yup, exact same thing here...same setup too...probably due to the larger diameter headers.
____________
FYYFF!!!
|
tonytooth
Zone Head
Posts: 647
|
posted September 15, 2006 06:31 AM
Edited By: tonytooth on 15 Sep 2006 07:36
I think my headers are the biggest diameter available for the zx14 so this may explain why I have more popping issues than other people I know. I ride with a guy with a Muzzy full system and a guy with a Gen3 system. There pipes are not as big as mine. Tiforce is known for there large diameter pipes. This is the reason I bought it, not to mention I love the look of the high mount.
I went out last night and looked for this area of no fuel and you can find it. I would ride the bike up to about 8k rpm then let off completely until about 4k and slowly move on the throttle about 5% and if you listen closely you can here the fuel come on.
|
|
|
HOME
NEW TOPIC