Eliminating popping on decel

[RiderCoach Lar]

I'm running a Holeshot full system and a PCIII with Dale's map on my '03. I get a fair amount of popping on deceleration; more than a fair amount when the bike is cold.

It's been suggested to me that this could be reduced or eliminated by simply plugging the hose from the air box to the Air Induction System. My question is, besides jacking with my CO and HC emissions (and hopefully eliminating the popping), is there any potential harm that can be done by simply plugging this hose??

 

[Mike-H]

This may sound dumb.....but are you sure you have no air leaks in the exhaust itself?....

 

[RiderCoach Lar]

This may sound dumb.....but are you sure you have no air leaks in the exhaust itself?....

That's not dumb at all. That's the first thing that came to mind, however, I'm pretty darn sure there are no leaks.

 

[radman]

It is the air system doing it, I and others have removed it, stopping the pop. Doesn't harm anything, mine has been disconnected for thousands of miles with no effect other than cleaning up access to the engine area.

 

[Wicked Webby]

Radman,

+1 on that. I agree completely. All of my Kawi's have had a similar system (KLEEN) and removal made for a pop free decel.

WW

 

[ELP_JC]

...with no effect other than cleaning up access to the engine area.

Indeed.

JC

 

[dgfella]

Sorry guys, when you say removing the 'air system', what exactly do you mean?

My full Holeshot system pops on decel only when the engine is cold, and only for the first minute of runtime.

FYI, I noticed on Dale's site that he has hints on this problem for other bikes like the SV650.

 

[radman]

Air Injection Reactor-it's the fresh air system that routes cold outside air through reed valves via a solenoid operated valve on top of the engine compartment. You can see it as it routes air from the air filter housing, through the valve which has a electric plug on it (it's operated by the ECM) then into 4 hoses running into the valve cover. I pulled it all, capped the reed valve inlets with rubber caps using the original clamps, and no more popping, and without the cats, there is no need for it anyway.

 

[dgfella]

radman,

OK, now I see what you are talking about. Any chance that you could do a write up? Looking at the shop manual, this seems like a simple mod. Where did you get the caps to plug the holes?

Every time I look at the engine compartment of my FJR, I yearn for the days of my CB750. Of course, twisting the FJR throttle makes it all better.

dgfella

 

[05fjrBluedevil]

radman,
OK, now I see what you are talking about. Any chance that you could do a write up? Looking at the shop manual, this seems like a simple mod. Where did you get the caps to plug the holes?

Every time I look at the engine compartment of my FJR, I yearn for the days of my CB750. Of course, twisting the FJR throttle makes it all better.

dgfella

I wonder how removing this will affect warranty issues, say if i hear a tick tick tick?

I also wonder if i need to replace the stock exhaust prior to taking it in for service?

Mike

 

[radman]

Tis as easy to reinstall as it is to remove, if thats a concern. Generally, one is ok with mods as long as a warrantyable problem cannot be traced to the modification-subject to the mood and intelligence of the service writer of course.

OK, now I see what you are talking about. Any chance that you could do a write up? Looking at the shop manual, this seems like a simple mod. Where did you get the caps to plug the holes?

DG, the caps are found at hardware stores everywhere, just try to stay away from those easily affected by heat-mine are heavy vinyl construction, and seem to be holding up well (to my surprise). One could also do as Jestal did, and actually tap and plug the air tubes where they enter into the exhaust port.

 

[Wicked Webby]

Tis as easy to reinstall as it is to remove, if thats a concern. Generally, one is ok with mods as long as a warrantyable problem cannot be traced to the modification-subject to the mood and intelligence of the service writer of course.

OK, now I see what you are talking about. Any chance that you could do a write up? Looking at the shop manual, this seems like a simple mod. Where did you get the caps to plug the holes?

DG, the caps are found at hardware stores everywhere, just try to stay away from those easily affected by heat-mine are heavy vinyl construction, and seem to be holding up well (to my surprise). One could also do as Jestal did, and actually tap and plug the air tubes where they enter into the exhaust port.

Radman, Or anyone else that has done this.....

Old topic here BUT... Did you unplug the solenoid? I was thinking that the removal of it would flip a code (check Eng. light). Or did you just leave it plugged in and cap the other end? Does anyone make the actual block off plates for this application so one could actual remove the pipe??

WW

 

[radman]

Unplugging the solenoid sets no code-not part of the feedback system. It does aid the cats in doing their thing-having the HS header it's not a concern for me. Block off plates aren't available as far as I know-some have made their own.

 

[ionbeam]

As a side note, the solenoid is normally ON (allows air injection into the exhaust) when there is no power to the connector, such as when it is unplugged. When 12 volts is supplied to the solenoid it shuts OFF and stops air from flowing into the exhaust.

 

[jekirby]

Mine (pciii and stock header/cans) does this but only on steep declines and in 2nd when using engine to aid decel. My question: would ignoring the condition damage anything in any way? It's not a backfire. I have just learned that there are circustances that I cannot use the engine to slow.

 

[radman]

Mine (pciii and stock header/cans) does this but only on steep declines and in 2nd when using engine to aid decel. My question: would ignoring the condition damage anything in any way? It's not a backfire. I have just learned that there are circustances that I cannot use the engine to slow.

It doesn't hurt anything, but it could lead to pipe discoloration, if that bothers you. The popping is unburned gases lighting off due to the heat in the exhaust system, aided by the fresh air supplied by the AIR. It occurs in the stock system also, but is well muffled. The addition of a PCIII exacerbates the problem due to the enriched fuel supply it provides.

 

[jekirby]

Mine (pciii and stock header/cans) does this but only on steep declines and in 2nd when using engine to aid decel. My question: would ignoring the condition damage anything in any way? It's not a backfire. I have just learned that there are circustances that I cannot use the engine to slow.

It doesn't hurt anything, but it could lead to pipe discoloration, if that bothers you. The popping is unburned gases lighting off due to the heat in the exhaust system, aided by the fresh air supplied by the AIR. It occurs in the stock system also, but is well muffled. The addition of a PCIII exacerbates the problem due to the enriched fuel supply it provides.

:good:

 

[thompsonian]

I must be odd, I love the popping sound :crazy:

 

[Jagermeister]

I must be odd, I love the popping sound :crazy:

Me too. Kinda nostalgic, like a '69 Camaro small block.