Decelaration popping and backfires
Tourer
Joined: Jan 2008
Posts: 274
Likes: 0
From: South Texas
The first thing my tuner did was to tighten up the head pipes to the heads. Made me real nervous because I had torqued them to spec and I could swear that he was swinging off the wrench at the end. haha. He said any exhaust leaks will mess up the tune. Even then, the first few runs on the dyno there were lots of decel pops. By the time the three hours of tuning was done, there were no pops. So, in short, it may be a combination of both. Hope that helps.
Road Master
Joined: Jun 2008
Posts: 868
Likes: 1
From: Trenton,N.J.
I just had my Ultra Classic Dyno'd (84.5hp,104.5tq) and it runs good but I have 2 issues--it pops and backfires on decelaration and it still runs just as hot as it did before the Dyno (I have an oil cooler and oil temp gauge installed along with the 103 stage 2 kit with se255 cams).
Is this an indication that it is still running lean?
Any advice on what can be done about the popping and backfiring?
Is this an indication that it is still running lean?
Any advice on what can be done about the popping and backfiring?
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Intermediate
Joined: May 2010
Posts: 32
Likes: 0
From: Friendswood, Texas
As stated before,it's your tune!!!The fuel & air ratios are not correct.The bike is running hot because it's not dailed in correctly.Take the bike to a private Indy who is fluent with the SERT,or the newest version the Pro tuner ,or even the TTS Mastertuner.The TTS is the cadillac of all tuners,but you have to find a tuner who is fluent with it's use.If I were you, I would use the TTS.It's the same people who made the SERT for Harley,but it's a newer improved version.
I will look into finding a good local Indy!! What does a TTS cost?
Anyone know of a good Indy in the Houston area that is a Dyno espert?
Road Warrior
Joined: Sep 2009
Posts: 1,472
Likes: 8
From: Blind Bay, BC
If I where you, as stated above check for leaks as your tune will be NFG with any fuel manager or dyno tune.
If you are considering a new fuel manager check out the Thundermax w/autotune and you will have NO NEED to pay a tuner, get on ride it and it will tune itself.
good luck with finding/resolving you issue.
Colin
If you are considering a new fuel manager check out the Thundermax w/autotune and you will have NO NEED to pay a tuner, get on ride it and it will tune itself.
good luck with finding/resolving you issue.
Colin
Seasoned HDF Member
Joined: Jun 2005
Posts: 12,946
Likes: 32
From: Colorado Springs, CO
popping=lean condition.
New EFI bikes when the throttle is quickly released go into a lean mode. It's part of the EPA smog setup in an effort to reduce emissions.
It CAN be tuned out, but you have to find a tuner that actually knows what they're doing.
~Joe
New EFI bikes when the throttle is quickly released go into a lean mode. It's part of the EPA smog setup in an effort to reduce emissions.
It CAN be tuned out, but you have to find a tuner that actually knows what they're doing.
~Joe
Road Master
Joined: Jun 2008
Posts: 868
Likes: 1
From: Trenton,N.J.
I paid between 300-400 for my mastertune.the dyno will be separate.if you can't find a tuner call doc at hdmd tuning center.you can google it & get the number.he can tell you who he has trained in your area on the mastertune.after you get it done,trust me it will run like it should!!!!
Tourer
Joined: Aug 2010
Posts: 451
Likes: 4
From: Oakland, Ca
My new to me 09 RK ran "acceptable" stock. No backfiring/popping, but did run hot. I installed a set of pipes, SE/KN filer and had the dealer do a generic HD stage 1 map. It ran better and fixed the fast idle...........(caused by the new exhaust/air filter)......., but had backfiring/popping problems..........(not real bad, but there, never-less).
I am "asssuming" the HD map was a epa friendly.??
Also still ran hot.
1 week later I installed 2-1-2 head pipe system and had an indy do the map that came with the cat free head pipe.
A little lower idle speed.......(a good thing as far as I am concerned)...... it runs great with NO backfiring/popping.
Also runs a bit cooler. The engine is a VERY happy camper...........a world of differance.
Have a good talk with your turner.....like others have said.
Just my $.02
I am "asssuming" the HD map was a epa friendly.??
Also still ran hot.
1 week later I installed 2-1-2 head pipe system and had an indy do the map that came with the cat free head pipe.
A little lower idle speed.......(a good thing as far as I am concerned)...... it runs great with NO backfiring/popping.
Also runs a bit cooler. The engine is a VERY happy camper...........a world of differance.
Have a good talk with your turner.....like others have said.
Just my $.02
Road Warrior
Joined: Nov 2008
Posts: 1,955
Likes: 7
From: The Great Northwest
I dont have any experience with the SERT, But.... with the PCV it is simple hook-up to the laptop and a quick fuel adjustment that solved my problem. Is the SERT user friendly? Can you make adjustments on your own? If so... I would take the following advice. My problem was totally solved by adding a small amount of fuel to both tables from the 1500 and up rpm range in the zero throttle column.
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Stellar HDF Member
Joined: Sep 2007
Posts: 2,459
Likes: 674
From: Vancouver Island B.C.
If it's not an exhaust leak then it is the perfect combination of fuel and exhaust to ignite. All that has to be done is upset the balance, usually by richening up the afr in the 20 map column on your afr table. They probably used the 009SAH map which still has the bike in closed loop in that area. You could probably try .925 lambda (13.5 afr) from a little higher rpm than where the popping starts. That should make a difference, but you may have to go as low as .877. If they only spent an hour on your bike it is definately not tuned.
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Intermediate
Joined: May 2010
Posts: 32
Likes: 0
From: Friendswood, Texas
Thanks everyone---I will have to go back to the dealer once and try to get this resolved. I appreciate all of the suggestions so I can use them in describing what may be happening and discussing this with the tech.
If I dont get results there I will have to go the PCV or TTS mastertune route and find a good tuner here in the Houston area.
If I dont get results there I will have to go the PCV or TTS mastertune route and find a good tuner here in the Houston area.
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