Need Help Deceleration Pop!!!!!!!!!!!
Login  | |
|
Need Help Deceleration Pop!!!!!!!!!!! - 3/11/2008 6:10:11 PM
|
|
|
Camman
Posts: 104
Joined: 4/23/2006
Status: offline
|
I have a 06 cbr 1000. It has arta full system, pair mod, power commander. I having a problem with deceleration popping almost like backfires. It sounds like a grand finale. I brought the bike from a good friend I cant remember if it always made the popping or if it started with the pair mod. If it was warmer out I would post a vid. It almost sounds like a super bike. Is this bad or hard on the motor. Has anyone else had this problem. Also the bike has about 6,000 miles on it.
|
|
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/11/2008 6:14:56 PM
|
|
|
BC1000RR
Posts: 66
Joined: 2/1/2007
Status: offline
|
I hear it all the time when downshifting for a corner at the track. Don't ride that hard on the street but if you hitting the redline then down shifting while breaking you are going to get a pop. Don't know if it is bad for it or not though.
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/11/2008 6:22:44 PM
|
|
|
Camman
Posts: 104
Joined: 4/23/2006
Status: offline
|
No I don't hit the limiter or red line. It will don't it any time over 10,000 rpms. It will also do it if I ride the same speed around 70 mph. For along pried of it right when I cut gas (pop).
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/11/2008 6:57:31 PM
|
|
|
openclasspro
Posts: 299
Joined: 4/16/2006
Status: offline
|
is it custom mapped?
_____________________________
2006 cbr 1000rr
pc3usb
air-flapper mod
Arata titanium trapezoid slip-on
BMC race air filters
Amsoil MC 10w40 oil,eaOM 103 filter
155.5 hp
82.3 ft.lbs.tq.
www.superbikesupply.com
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/11/2008 7:24:03 PM
|
|
|
bboi
Posts: 478
Joined: 5/4/2006
Status: offline
|
sounds like you need it mapped
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/11/2008 9:46:33 PM
|
|
|
Blue Fox
Posts: 4575
Joined: 7/14/2006
From: Las Cruces, NM
Status: offline
|
+1 to both above posts. Need to take it to a performance shop and have it mapped.
< Message edited by Blue Fox -- 3/11/2008 9:52:07 PM >
_____________________________
Want the LED headlamps? http://cbrforum.com/m_681535/tm.htm Powder Coating TOO!
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/12/2008 9:08:04 AM
|
|
|
Ty
Posts: 251
Joined: 8/2/2007
Status: offline
|
+1 on a good fuel map. My friend's bike did that for the longest time until he had it tuned. It was actually kind of cool to see the flames shoot out every time he let of the gas. Shame he got it fixed.
_____________________________
If speed was a drug I'd be dead by now. Wait...that doesn't make any sense...I'm hooked on all sorts of sh*t and that never killed me. OK...if speed negatively reacted with drugs and alcohol....DAMMIT!!
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/12/2008 11:51:44 AM
|
|
|
sweetdeal
Posts: 249
Joined: 12/9/2007
Status: offline
|
popping is usually (not always) caused by the engine running to lean.
When you have it wide open and then cut the throttle, Think of it as your bike taking in a huge breath of air (especially with your mods) and just as your half way through your big breath someone hits you in the stomach... You cough... Basically when it is open throttle tons of air is coming in then you cut the throttle, as a result the ECU says wait STOP the fuel flow, but the air is already there, causeing a greater air to fuel ratio...
and more air+less fuel = explosion instead, of "fast burning"
You could fix most of this with a good custom map. Keep in mind though If it is too lean you will ruin a motor. Remember this is good for PROS because Lean=HP but...When they run it lean they burn through motors, and i am pretty sure most of us don't have a factory sponsor to give us new motors when ever we want.
_____________________________
"if everything is under control your going to slow"
~Mario Andretti
2006 CBR 1000rr Candy Blue / Yellow
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/12/2008 2:43:19 PM
|
|
|
MgA_ODEN
2005 Ride Of
The Year
Posts: 2072
Joined: 4/19/2005
From: Spring , Tx
Status: offline
|
Are you sure it has the PAIR mod done to it?
_____________________________
Black 2004 CBR1000RR
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/12/2008 4:17:59 PM
|
|
|
Camman
Posts: 104
Joined: 4/23/2006
Status: offline
|
Am sure about the pair mod. Why do you ask? Im also so that the bike is not leaning out.
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/13/2008 5:37:39 AM
|
|
|
Ty
Posts: 251
Joined: 8/2/2007
Status: offline
|
Afterfires are from running rich, not lean. Air goes through the motor no matter what because the valves are mechanical and the opening and closing doesn't change, except for vtec but that's beside the point. When there is extra fuel, like bikes are tuned to have, there is only enough air to burn most of the fuel and the unburnt fuel is ejected out of the motor and into the exhaust. The PAIR lets air into the exhaust on decel with the intention of lighting off the unburnt fuel within the confines of the stock exhaust system thereby creating little to no noticable afterfire.
When you swap the exhaust out, you are increasing the flow of exhaust gasses, moving the little explosions further down the pipe and muffling them less. With the PAIR disabled, you are no longer allowing air into the exhaust on deceleration so the ony way for the fuel to burn is to travel all the way through the exhaust until it reaches fresh air. Your popping on decel is the effect of that. More than likely you are shooting flames out of your exhaust as well each time you let off the gas. A custom fuel map will keep the A/F ratio within the correct range and do away with most or all of your problem.
_____________________________
If speed was a drug I'd be dead by now. Wait...that doesn't make any sense...I'm hooked on all sorts of sh*t and that never killed me. OK...if speed negatively reacted with drugs and alcohol....DAMMIT!!
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/13/2008 7:09:34 AM
|
|
|
sweetdeal
Posts: 249
Joined: 12/9/2007
Status: offline
|
quote:
ORIGINAL: Ty
Afterfires are from running rich, not lean.
I have to disagree and refer back to my "lean" explanation. When running rich "Un burnt fuel vapor" is released through the exhaust valve and out with exhaust emmisions, Once the exhaust vale open and releases the "unburnt fuel" it will not reignite causeing a back fire or popping. There is no source of ignition to re ignite the "unburn fuel". Explosions or back fires are results of too much air mixed with not enough fuel.
You ever dropped a match into a gas tank it goes out, but when you hold a match over the vapors they ignite. IF you move a match close to small container of fuel it will ignite the air directly above the fuel and a falme will burn steady, it will not explode.
Remember this is a 4 cycle engine, one cycle of the piston is ignition, the next is the opening of the valves, releasing "unburnt fuel" and exhaust gases. once this fuel leaves the ignition chamber it won't reignite. The term rich came from the "rich smell of gas in the exhaust fumes. So therefore if it was "exploding" and popping, i.e burning off... they never would have coined the term, because there wouldn't have been a strong smell of gas.
_____________________________
"if everything is under control your going to slow"
~Mario Andretti
2006 CBR 1000rr Candy Blue / Yellow
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/13/2008 8:18:34 AM
|
|
|
Ty
Posts: 251
Joined: 8/2/2007
Status: offline
|
Do you think I just make this stuff up? Who tells you these things?
I assume that you have seen common movies like Fast and Furious or some street racing vids or something. I know that most of it is fake but the flames blowing out the back of the cars is real. In order to do that, you simply turn your amount of fuel up until flames shoot out. It happens in cars that have non-boost-based fuel controllers or when the intake pressure is vented to the atmosphere on deceleration.
The flashpoint of fuel vapor is far lower than the internal temperature of the exhaust, thus the fuel will ignite supposing there is enough oxygen to mix with. If there is not enough fuel (lean), the fuel that is present will burn with the appropriate amount of air and the leftover air simply gets heated up and leaves through the exhaust valves and then out the exhaust with no further drama. There is no fuel left, so the air is incapable of burning with anything.
If there is too much fuel, the available air is used and there is leftover fuel vapor in the cylinder that is past its flashpoint but has no air to mix with, thus preventing combustion. As soon as this heated fuel vapor contacts air, it is ignited. That is the entire purpose of the PAIR system. It introduces air to the exhaust on decel to burn the exiting unburnt fuel vapor so as to remain within the federal guidelines for the exhausting of unburnt fuel vapor. When the exhaust is changed to not have a cat or much muffling capacity, the popping of the igniting fuel vapor within the exhaust is more audible. This always happens, it's just that Honda doesn't engineer the bike for free flowing exhaust.
Anyway, when you let off the throttle at high RPM, or even lower RPM, the fuel injectors are spinning so fast that they cannot stop flowing fuel the exact instant that you let off the throttle. Your throttle plates, however, are connected to the throttle grip via a cable and mechanically close exactly with the turn of your wrist. The resulting lack of air and increase in vacuum pressure leaves more fuel than air in the combustion chamber. The air is fully used, and like I said above, the unburnt fuel vapor that is left over enters the exhaust well past its flashpoint. As the vapor encounters air in the exhaust, from the next cycle of the cylinder or as it leaves the exhaust, it will combust. The combustion can be very small and heard as slight popping, which is normal, or it can be quite volatile and result in flames shooting out and loud popping, which is not normal but indicates a temporary rich condition.
An adjustment lowering the amount of fuel entering the system on decel is needed.
Please research this on your own prior to arguing with me. Your assumptions about AF ratios could cost somebody serious amounts of money. I'm not trying to call you out, but the kid asked for help and you are telling him the opposite of what is going on. And yes, as a racer and an engineer, I am aware that this is a four cycle engine jackass.
_____________________________
If speed was a drug I'd be dead by now. Wait...that doesn't make any sense...I'm hooked on all sorts of sh*t and that never killed me. OK...if speed negatively reacted with drugs and alcohol....DAMMIT!!
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/13/2008 9:41:28 AM
|
|
|
sweetdeal
Posts: 249
Joined: 12/9/2007
Status: offline
|
First of all the forum screwed up and the message didn't get through before you could repost this long unnecessary post but i will retype it and hope it works this time,
I never once gave any advice saying what to do or not to do that would cost any one money. Second i too am an engineerand (jet engines to be exact) i deal with suck, bang, blow, theory all day. and air fuel mixtures.
What i tried to say before you got all huffy and puffy and resorted to name calling, Was that both of of our theorys are correct, about lean and rich (ness) can cause back fireing, when you close a throttle after a had pull it creates an increase in vaccum pressure (we both agree on) however when that valve closes from the throttle it is not air tight it has to allow some air in for idle reasons, but the increase vaccum is still sucking some air in on top of the increase amoutn from wide open throttle amounts(even more with mods) the only part i disagree with you is the injectors. I say they stop before air flow, you say they stop after airflow. They are controlled by electronic pump , the air entering into an engine is controlled by "fluid dynamics" i.e. vaccum and the flow of air pressures (not instant), anyways the increase air is going to cause popping within the engine as the engine continues to make revolutions (until vaccum pressures decreas) popping occurs because it is sucking more air, but injectors are reducing fuel causeing a lean mixture which more oxy means bigger more powerful burns.,
Yes you are rigth with increased fuel it will cause a backfire and flames. NOW back to your claim about fast and the furious cars... i agree with you to some extent, but most of those cars blowing flames are due to boost, because when you boost a car your adding more pressure into a cylinder with air causeing a bigger more powerful burn. or these cars are running with NOS which all it does it increase a high mixture of oxygen into the mix again causeing bigger more powerful burn. Fuel doesn't burn without oxygen the more oxygen you get the bigger the burn or explosion. Flames occur because no car is 100% efficiant and there will always be unburnt fuel but because of being a lean running engine, it is also a hotter running engine and this means hotter exhaust to burn unspent fuel causeing flames.
We are both rigth so back to my original solution "TAKE IT TO HAVE IT RE-MAPPED" that advice is not goign to cause him $$$$ because it solves your theory and mine. so unless there is something else you want to bring up let me know.
_____________________________
"if everything is under control your going to slow"
~Mario Andretti
2006 CBR 1000rr Candy Blue / Yellow
|
|
|
|
|
RE: Need Help Deceleration Pop!!!!!!!!!!! - 3/13/2008 11:55:45 AM
|
|
|
Ty
Posts: 251
Joined: 8/2/2007
Status: offline
|
Man you are missing some information.
First, a BACKFIRE is combustion within the intake tract of the engine usually associated with a lean condition on carburated vehicles. The slow burn due to the lean condition can "chase" the flame back out of the intake valves because the flame gets behind the timing, so to speak. That's why carbs need to be cleaned and set. Maybe that's what your thinking of.
An AFTERFIRE is what we are talking about, caused by a rich condition. An afterfire takes place in the exhaust tract, and cannot be caused by a lean condition. The flames on boosted cars are from running purposefully rich without compensatory boost-based AF controllers. If I make 15 pounds of boost at WOT at 5000 RPM, then I tune my fuel system to deliver that amount of fuel. Obviously, I can only create that amount of boost in high gears and do not always need that much fuel. In lower gears or while sitting still, much more fuel is delivered to the combustion chamber than is required and is burned when it reaches a source of air, which in most cases is the end of the exhaust pipe. The flames are from not having enough boost to support the amount of fuel entering the chamber, otherwise known as rich. Air cannot simply burn on its own, otherwise the whole world would explode every time I light a cigarette.
There is no possible way that lean conditions can create afterfire. Nor does the amount of air in the combustion chamber have any capability to light off in the exhaust without fuel. I thought it was common knowledge that a temporary rich condition is created on immediate deceleration. There will always be fuel spilled because one of the cylinders is always on the intake stroke when the throttle plates are closed. The computer has already calculated the fuel and then the cylinder gets half the air that it was supposed to get due to the intake vacuum upon throttle release. Depending on the speed of the processor in the fuel computer, this can continue for several cycles depending on the RPM at the time.
12,000 RPM means 6000 RPM injector speed, times four cylinders means that the injectors are firing 24,000 times per minute. That's every 2.5 milliseconds. Can your fuel controller make adjustments to intake pressures and throttle setting in less than 2.5 milliseconds? If your computer has a response rate of 10 milliseconds (which is extremely fast), the engine will have one stroke on each cylinder that recieves fuel without the appropriate amount of air during a 12,000 RPM throttle-off because the throttle plates are closed and the intake will have vacuum pressure after only one stroke by one cylinder. More realistic would be about 100 milliseconds for a factory controller and 50 for an aftermarket controller. The reason the aftermarket controllers are faster is that they use less information to determine the amount of fuel needed as well as that they do not share processor space with other systems as a vehicle would.
I do not doubt that you have abilities as a jet mechanic. The correlation between the two is non-existant, with the exception that they both turn air and fuel into propulsion. I would encourage you to research vehicle engine operation due to the vast differences.
And I only called you a jackass because you asked if I knew that this was a 4-stroke engine, lol. I take it back.
_____________________________
If speed was a drug I'd be dead by now. Wait...that doesn't make any sense...I'm hooked on all sorts of sh*t and that never killed me. OK...if speed negatively reacted with drugs and alcohol....DAMMIT!!
|
|
|
|
 Today's Posts
Most Active Topics
Make A Donation
Forum Rules & FAQ
RSS Feeds
Advertising Info
|
Contact Us |
Advertising |
Automotive Directory |
About Us |
Archive |
Honda CBR Motorcycle Links |
Legal |
Privacy Policy |
© CBR Forum
CBR Forum .com is not affiliated with or endorsed by Honda Motor Company.
|
Printable Version
