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TheBuilder
06-05-2014, 07:41 PM
So as the title says I've been getting the odd backfire through the carbs and air box. It seems to be mostly after decelerating and coming to a stop or all most stop. Has any one else had backfiring into the air box?

Mike06
06-24-2014, 02:50 AM
Hi, I also have backfiring into the airbox.

My bike has 2500kms now and the backfiring was there since it was brand new.
It happens when I slightly accelerate from the iddle and the bike almost stalls.
I took down the tank and airbox yesterday to check something and I found a little gas in the airbox around the entrance of the back cylinder admission pipe.
The backfirings also broke in pieces the two brackets around the frame where we have to screw the bolts through the front of the tank...
I think the valve clearance is bad but maybe it's another issue ?

Did it happens to someone else ?

PS : sorry for my bad english, I'm french and I try to remind me my school years but they are far away in my memory...

tfunk8360
07-01-2014, 06:40 AM
I also have thisn problem. also my bike is starting to surge when I try to maintain a constant speed. I just hit 17,000 miles and have the original spark plugs. can any help me solve this problem

xactoman
07-10-2014, 03:01 PM
I think mine is doing this too, but I wouldn't classify it as a backfire, more of a misfire. Usually happens at a stop when the bike is idling...go to roll on the throttle and the bike gasps, more of a vocal cough through the exhaust. Bike will die if the clutch gets let out. Have to grab a hand full of clutch and let off the throttle or it dies. It's a hard thing to describe, almost as if the engine chokes under the weight of it's compression; like one cylinder isn't firing at the right time. Maybe it's too rich and igniting fuel on the exhaust cycle. Or maybe it's just fine italian character.

Do any of you run the fat duc? I thought that maybe that was the case and backed mine off. hasn't really helped much.

Mr.Dorso
07-10-2014, 09:59 PM
Not running fatduc and experiencing same issue. Just had demand sensor replaced and still issue with misfire and engine braking, especially in 4th gear above 3000rpm, very snappy and abrupt engine braking.. Very frustrating dealer can't diagnose issue and Italy said faulty demand sensor yet issue still there, bike is going back in again next week

TheBuilder
07-11-2014, 06:26 AM
Ya I have the fatduc in mine. Mine seems to do it more often if I'm putting around town and also if the weather is hot and humid. I'm leaning toward unburnt fuel igniting at the wrong time either due to plugs with the wrong heat range or plugs carbon'd up enough that it stays hot enough to burn the left over fuel. Really not sure what it's doing :S

xactoman
07-11-2014, 09:09 AM
What engine mode do you guys run in? I initially thought it could have something to do with "S" mode. Appears that mode has stronger engine braking and I remember hearing someplace that it changes the ignition/timing, but could be wrong. That could be an cause of a harsher ignition scheme.

Mike06
07-13-2014, 05:24 AM
I read on the italian DD forum that many owners have this problem with the new map.
They advised the Aprilia factory in Noale and await their response.

Here's the link for those who understand Italian :
http://lnx.dorsoduroforum.com/forum/...p?f=36&t=11701 (http://lnx.dorsoduroforum.com/forum/viewtopic.php?f=36&t=11701)

luzik
07-20-2014, 04:33 AM
Any more news about this issue ?

TheBuilder
07-20-2014, 08:31 AM
I'm assuming not but does anyone know if you can go back to different map updates?

luzik
07-20-2014, 09:42 AM
https://www.youtube.com/watch?v=I6OwaYIok5U
look at 1:45 and 2:04
are we talking about same issue here ?

Mike06
07-20-2014, 09:54 AM
Exactly the same issue for me !

luzik
07-20-2014, 10:13 AM
I have additionally issue. Sometimes while riding after closing throttle (engine breaking) when i open throttle again a bit (just a little) my dorso can't decide - accelerate or not ..it accelerate, then slow down for a second then accelerate again.
Is it related ? to backfire, choke ?

TheBuilder
07-20-2014, 12:37 PM
@Luzik

Ya Id say that pretty much what I have too. I've had them bad enough that it stalls the bike.

luzik
07-20-2014, 02:09 PM
today i connected guzidiag http://www.apriliaforum.com/forums/showthread.php?282399-Guzzidiag-for-RSV4 and find out that air pressure in rear cilinder differs from front one ..even on idle !

Mike06
07-21-2014, 01:30 AM
That's what I thought... but is the pressure really different or the back cylinder air pressure sensor who gives bad information ?
Or something to adjust on the map ?
Aprilia factory we need help !

luzik
07-21-2014, 01:54 AM
This is the right question !
But i don't have gaskets to swap sensors

luzik
07-21-2014, 02:58 AM
I have two dorso 1200 - 2011 after crash, and 2012 ..yesterday i swap ECU (old bike have old software) and everything back to normal now. Eh..

Mike06
07-21-2014, 04:13 AM
Ok so the issue is on the latest maps... so we only have to wait Aprilia releases a new map, or do a map by ourselves !
Just to be sure : did you see a difference between the two ECUs (serial number or something) ?

luzik
07-21-2014, 04:56 AM
Just to be sure : did you see a difference between the two ECUs (serial number or something) ?
Yes, but main numbers are the same IAW 7SM.A8

In my humble opinion this issue is not only related with a map.
I see this in a way that new software require more accurate hardware work, because some of us do not have such problems with new soft.
The big question is to find out what part of the engine need to be fixed. (valves? some of sensors? throtles?)

Mike06
07-21-2014, 05:57 AM
Maybe the range of the air pressure sensor (which I think it's the same as older models) is not accurate enough to calculate the settings that the latest maps need ?

TheBuilder
07-21-2014, 11:13 AM
I suspect it has more to do with timing advance and fueling than sensor ability.

Mike06
07-21-2014, 01:29 PM
Anyway not easy to find...

TheBuilder
07-22-2014, 09:57 AM
Does anyone happen to know what the release date was of the update that is creating this problem?

luzik
07-22-2014, 12:28 PM
It was released on 03. or 04.2013
ver. 1338EA.07

two months ago it was the newest version available. We have to wait. But I don;t know if any one from aprilia know about this issue. Did any one of you go with this problem to local service (dealer) ?

TheBuilder
07-22-2014, 12:53 PM
That seems odd. I've had the bike updated twice. Once in July of 2013 when I bought the bike and once this spring after I tried the Rexxar tune(that was pointless) It would have been the same update both times....?
Didn't have the problem till the latest update.

trainman
07-22-2014, 03:28 PM
It was released on 03. or 04.2013
ver. 1338EA.07

two months ago it was the newest version available. We have to wait. But I don;t know if any one from aprilia know about this issue. Did any one of you go with this problem to local service (dealer) ?


this is the update I had about 7 months ago, worked fine, I was told it by dealer that it improves smoothness and fuel cons and I agree it has (my bike is stock), it also did something to the way the lambda probe signal was used

there was a special procedure dealer did after loading for bike to learn something, maybe throttle position? did yours get this?

TheBuilder
07-22-2014, 04:21 PM
I'm pretty sure this was the update I did last year and it worked quite well except a bit of lean surging.

TheBuilder
07-22-2014, 04:24 PM
Mr Dorso when did you get your update back to the stock map?

Mr.Dorso
07-22-2014, 05:12 PM
17.04.14

TheBuilder
07-22-2014, 08:05 PM
That's not too far off when I did mine. There must be something more recent then the 2013 map.

luzik
07-23-2014, 02:17 PM
http://lnx.dorsoduroforum.com/forum/viewtopic.php?f=36&t=11701

Post is from "18 aprile 2013"

put this page into google translate
https://translate.google.com/translate?hl=pl&sl=it&tl=en&u=http%3A%2F%2Flnx.dorsoduroforum.com%2Fforum%2Fvi ewtopic.php%3Ff%3D36%26t%3D11701

they are talking about "pufs" just after upgrade

can you agree that our issues depends on weather ?

for example lower temperature ..more problems ???

stockell_mat
07-23-2014, 04:14 PM
I had the misfire /backfire through the air box last summer, straight after having a new map installed. It got so bad I had to constantly hold the clutch in traffic for fear of stalling. I found that the problem was solved by having the ecu map reinstalled and put it down to the map not being properly bedded in.

TheBuilder
07-23-2014, 07:17 PM
The bike goes in Saturday so hopefully we can figure out what the deal is.

luzik
07-24-2014, 12:11 AM
My map was reinstalled, but it didn't helped. :-/

trainman
07-24-2014, 02:05 PM
My map was reinstalled, but it didn't helped. :-/

It can happen that software or dealers pc is corrupt or has a problem, ask them to use another copy on another machine with another connection lead, if they cannot try another dealer if possible?

luzik
07-25-2014, 02:39 AM
It can happen that software or dealers pc is corrupt or has a problem, ask them to use another copy on another machine with another connection lead, if they cannot try another dealer if possible?

First software update was done in Germany, second here in Poland ..so i suppose that the problem is in other place

Mike06
07-25-2014, 04:25 AM
First done in France (brand new 2014 DD 78kw), second in Italy in may (map full power), and 3 weeks ago a new update in France... backfires still there

luzik
07-25-2014, 04:51 AM
First done in France (brand new 2014 DD 78kw), second in Italy in may (map full power), and 3 weeks ago a new update in France... backfires still there

:-(

Did you talk about this with them ??

Mike06
07-25-2014, 05:38 AM
Yes I do !
They couldn't find anything, they checked valve clearance : ok, different sensors : ok...
I asked them to tell Aprilia France but I do not expect anything positive from them... so I'll try to see if someone on the Italian forum could contact the Aprilia factory talking about your case, mine and theirs. I would do it myself but I do not speak Italian well enough for that !

luzik
07-25-2014, 06:32 AM
Yeah ..i wrote in their thread about this software ..but can't understand a word :P

Mike06
07-25-2014, 06:36 AM
An italian member on the DorsoduroForum.com said this :

"I do not have that problem but I do not think it's something so normal. I, as an ignorant, always had a theory that this video confirms. The backfire, because that is clearly not a puff, is only on the rear cylinder (at least from the video) and when you increase the supply of gasoline. When I dismounted the candles I noticed that the rear ones clearly showed by the color excess gasoline, perhaps due to the need for cooling due to the lower air flow (you can cool off cylinders with air but also with the petrol).
Well, maybe I'm wrong, but it seems not so stupid . The gas builds up and then detonates !

Maybe iridium sparks could help ?"

It seems like a good theory isn't it ?

luzik
07-25-2014, 07:01 AM
Just like one of many which do match. But changing spark plugs sound like a quite cheep and easy to achive plan, especialy when I recall that someone told me that he solve some aprilia engin issue replacing NGK with Denso ones. ( U24ETR ? )

boki
07-25-2014, 09:10 AM
^And maybe try one step colder plugs while at it to try and prevent pre-ignition somewhat? I know from my car forums after increasing the HP with the tune (more PSI, more heat) it is required to install one or even two steps colder plugs (my stock spark plugs heat range was 6 and I installed 7 and have 8's on the order - NGK PFR7B and PFR8B for example).

Mike06
07-25-2014, 11:23 AM
Yes maybe... I did that on my Subaru after remapping but here it's not a boosted map, no HP increasing, only a new factory one ! Aprilia did a bad job and we have to find a solution by ourselves... boring !

boki
07-25-2014, 01:09 PM
^I know, no boost and not significant HP increasing but if they are leaning the AFR you'll get higher temperatures in the cylinders that might cause for the spark plugs to not get cooled enough in between firing and be prone to 'glowing' for the lack of better expression and thus causing the mixture to pre-ignite...in that case the one step colder plugs might just do the trick.

Mike06
07-25-2014, 01:18 PM
You're right, it's an option to consider...

trainman
07-26-2014, 02:42 AM
^I know, no boost and not significant HP increasing but if they are leaning the AFR you'll get higher temperatures in the cylinders that might cause for the spark plugs to not get cooled enough in between firing and be prone to 'glowing' for the lack of better expression and thus causing the mixture to pre-ignite...in that case the one step colder plugs might just do the trick.

is the problem better if you use a lower octane petrol?

boki
07-26-2014, 08:13 AM
is the problem better if you use a lower octane petrol?

^I'm not sure that the lower octane petrol would help here since lower the octane more it is prone to pre-igniting, if that's what happens here. This problem could also be because of the too rich of a mixture and if not all the petrol burn in the cylinders it could ignite in the exhaust or intake once the valves open. I don't have the DD1200 (currently own SXV 550) but I'm looking into buying one-maybe.

TheBuilder
07-26-2014, 02:31 PM
So I did a couple hour ride to the dealer and did another map update. And as usual the whole way to the dealer that bike ran fine. Not a miss or backfire the whole time. Did a map update anyway and it still seems good so far. I guess I'll wait and see how it goes.

Brinks_2
08-04-2014, 06:40 PM
Micah, calling Micah. I am wondering if he has had the valve covers off one yet to see where the cams are timed. Seems to me that aprilia are trying to fix by map alone, it would be interesting to see if the cam settings are "in tolerance" If anyone takes the covers off next, a check of the dial in would be interesting.

quiqueDD750
12-29-2014, 11:49 PM
Hi Guys, im from El Salvador, Central America, and I own a DD750, im having the same trouble, i have changed the Fuel Filter, Air Filter, New Spak plugs... and its still doing this problem, but it does it a lot... if I run the accelerator a lot of times up and down... it feels like some times the engine goes off and then on again, and you can hear the miss fire... do you have any news on the MAP?... where can i find something about the MAP, or Scan it, if i dont have any dealer here in my cpountry?

Thanks!

Mike06
04-02-2015, 11:59 AM
I still have the same problem ... it sucks in traffic jams ! :bangwall:
Someone found a solution ?

Locky
04-02-2015, 09:59 PM
Fuel with alcohol in it can cause this because it burns hotter it can cause hot spots on the valves and exhaust port that end up as an ignition source.I would think that if it was the mechanical timing it would do it on all 3 maps.

Gabro
04-03-2015, 12:18 AM
I still have the same problem ... it sucks in traffic jams ! :bangwall:
Someone found a solution ?

I may solved the issue, solution is being testing now in a customer bike (motor were stalling in traffic and coming out of a stop). Do you wonna be one of my test mule and send me your ECU? you'll pay only the shippings on and off

Mike06
04-03-2015, 01:49 AM
Thank you very much but I have to keep the original map from Aprilia because my bike is still under warranty...
So you are sure it is a map problem ?

Locky
04-03-2015, 08:28 AM
Has anyone tried a power commander on a dd1200?I would think contacting them might be worthwhile.Bikes with fuelling problems are how they make their living.....

Gabro
04-03-2015, 12:14 PM
Thank you very much but I have to keep the original map from Aprilia because my bike is still under warranty...
So you are sure it is a map problem ?

i already have a test bike running, and it looks to run fine till... just searching for new guinea pigs :D

PS i just had an idea, don't know if it works, but why don't try? remove the clutch micro-switch from the clutch master, use the tape to keep it always pushed, like it would be when the clutch lever is relased. go for a test ride and report ;)

Locky
04-05-2015, 01:12 AM
EMail: tournay@free.fr ('tournay@free.fr')
Web: www.tournay-distribution.com (http://www.tournay-distribution.com/) Have You tried these guys?

Chriz75
10-08-2015, 04:53 PM
Just curious why should the clutch micro-switch help ?
I got this issue also on my brand new DD1200... :(



i already have a test bike running, and it looks to run fine till... just searching for new guinea pigs :D

PS i just had an idea, don't know if it works, but why don't try? remove the clutch micro-switch from the clutch master, use the tape to keep it always pushed, like it would be when the clutch lever is relased. go for a test ride and report ;)

ozSh1rts
01-13-2016, 05:57 PM
I've had 3 map updates (according to the dealer) in 3 and a half years of owning a 2011 Dorso 1200; made no difference, I get the same backfiring/misfiring issue.

The last time they had the bike (FOR TWO MONTHS!) they gave it back saying they'd found the problem: - it was missing some O-rings between the manifold and the cylinder head. (wut?)

It *is* running better, it doesn't stall - as much. It still occasionally stalls and it still occasionally burps at traffic lights, quite often just as they go green and I'm alongside someone who's been yelling at me for lane splitting..

:-(

luzik
05-23-2016, 01:03 PM
Ok
Some new info with this issue
I changed whole throttle body with all sensors and throttles with it, new injectors etc. Old engine and old ECU - results ..? - no change at all !!!! ..problem was still there.
After that i changed engine and ECU - working like a charm ! (probably with old software ver.)

RATMOUL
05-24-2016, 11:27 AM
Hi, I also have backfiring into the airbox.

My bike has 2500kms now and the backfiring was there since it was brand new.
It happens when I slightly accelerate from the iddle and the bike almost stalls.
I took down the tank and airbox yesterday to check something and I found a little gas in the airbox around the entrance of the back cylinder admission pipe.
The backfirings also broke in pieces the two brackets around the frame where we have to screw the bolts through the front of the tank...
I think the valve clearance is bad but maybe it's another issue ?

Did it happens to someone else ?

PS : sorry for my bad english, I'm french and I try to remind me my school years but they are far away in my memory...

Hey Mike. Your English is certainly better than most of our French. Thanks for making the effort.
A lot of the backfiring is probably due to lean running in the 0 to 5000 rpm range. This was horrible with the initial map due to trying to get the bike through emissions testing, and only slightly improved on the subsequent version, which many of us have had installed. A Fatduc can take care of most of this usually. Mine came with this set up dialed in by the previous owner and it does not backfire. I believe he said that he settled on the mid setting of 13.5 after some playing. I would highly recommend this to anyone having trouble with low speed backfiring and general rough running at lower rpm. The Dorso 1200 can make a lot of low end torque and run very nice in this range, allowing you to run in a taller gear when cruising, which is much easier on the bike and helps out the fuel mileage tremendously.
Spark plugs, air temp sensor and valve clearances can of course have an effect, but these are tough well made engines that usually do not require much that way unless the bike spends most of it's life at the redline. My guess is that almost all of the problems with low speed running and backfiring can be sorted out with emc tuning and a Fatduc...... T

Mike06
05-25-2016, 01:23 AM
Thanks for your answer but I have a DNA airfilter and a fatduc... I will certainly send my ECU to Gabro and I think it's the only solution ! But I have to wait my waranty ends... :mad:

Chriz75
06-08-2016, 01:50 AM
i already have a test bike running, and it looks to run fine till... just searching for new guinea pigs :D

PS i just had an idea, don't know if it works, but why don't try? remove the clutch micro-switch from the clutch master, use the tape to keep it always pushed, like it would be when the clutch lever is relased. go for a test ride and report ;)


I must say that it feels like it reduces the backfire.
Yesterday before I taped the clutch micro-switch then it died at a red light where I had passed a lots of cars. Not so much fun I must say.
So I decieded to try the tape it on my way home and it did feel like it was less backfire. I got one small one. And on my way to work today it
also felt like the backfire was reduced.
Maybe Mike06 you can try to tape the clutch micro-switch also and see if you notice any differance.
But it also feels like the idle i a bit higher, but compared to the backfire that is not an issue.

I will some day send you my other ECU to you Gabro. :-)

Mike06
06-08-2016, 12:03 PM
I must say that it feels like it reduces the backfire.
Yesterday before I taped the clutch micro-switch then it died at a red light where I had passed a lots of cars. Not so much fun I must say.
So I decieded to try the tape it on my way home and it did feel like it was less backfire. I got one small one. And on my way to work today it
also felt like the backfire was reduced.
Maybe Mike06 you can try to tape the clutch micro-switch also and see if you notice any differance.
But it also feels like the idle i a bit higher, but compared to the backfire that is not an issue.

I will some day send you my other ECU to you Gabro. :-)

I tried to tape the clutch micro-switch but no change for me...

Currently my bike has less backfires, more in winter or in cold weather. It seems to almost disappear when the wheater is getting hotter or when I drive it in the mountains (up to 2000m).
More the air density is bigger, more there are backfires. So I think the Air Fuel Ratio around idle until 5000rpm is bad.

Gabro is our messiah !:angel:

RATMOUL
06-09-2016, 11:40 AM
I tried to tape the clutch micro-switch but no change for me...

Currently my bike has less backfires, more in winter or in cold weather. It seems to almost disappear when the wheater is getting hotter or when I drive it in the mountains (up to 2000m).
More the air density is bigger, more there are backfires. So I think the Air Fuel Ratio around idle until 5000rpm is bad.

Gabro is our messiah !:angel:

Hi Mike. Maybe a dumb question, but have you tried adjusting the Fatduc a bit towards the leaner side and see if this helps? T

Mike06
06-10-2016, 01:25 AM
Hi Mike. Maybe a dumb question, but have you tried adjusting the Fatduc a bit towards the leaner side and see if this helps? T

I tried all adjustments with the fatduc, from full clockwise to full counter flockwise...

Andrew Gill
12-25-2017, 02:26 PM
Has anyone ever sorted this problem out with the backfiring through the airbox..? I was going through the forum and decided to post to this thread as it seems there is sufficient build-up of information that someone may have found the solution..? My 2012 Dorsoduro 1200 has been intermittently doing the same since new..? It now has 22,000kms on the clock. Ive had it at Aprilia and they have run their P.A.D.S Diagnostics a number of times and still nothing..?�� The Diag. seems to correct or adjust something and then will run ok for a little while before going back to its old habits again. What I have noticed is that it seems to have something to do with the idle sensor.. or information or telemetry going to the throttle position at idle? As soon as the bike comes to a stop and the idling sometimes tends to be off target and seems to hunt for the right setting. The revs drop and it runs too low. Then, what I can only think is that it over supplies fuel to fix the problem - only to try afterwards and correct the 'too much' fuel by cutting the motor (or one cylinder) and then realises that 'nobody told it to completely cut the motor', and it resumes ignition and that causes the excess fuel now entering into the injector to ignite prematurely.. which finds its exit via the air-box?��

It would be good to know if anyone has been able to beat this problem..

RATMOUL
12-26-2017, 04:43 PM
I am not having this problem and my 2011 DD1200 is running very sweetly with the later program, a Fatduc, DNA filtre and GPR pipes.
It would seem that anyone having an ongoing problem with this might consider sending their ECU to Gabro for a custom reflash...... Tom

truck
01-15-2018, 07:10 AM
Hey guys. yet another DD owner with the same problem. just came across this thread and it is a slight comfort that I'm not the only one. But insanely frustrating that it is such a widely reported issue yet no one at Aprilia or polaris or whoever actually owns them care enough to fix the problem! what about AF1 racing guys? Haven't seen a single post about it from the people running the forum. Are you not allowed to comment on such issues due to contract reasons? Surely you have had customers bring their DD in for the same issue we are getting over quickly?

truck
01-15-2018, 07:13 AM
do we have confirmation or proof that gabro's reflash works?

maddevill
01-15-2018, 04:34 PM
Generally, backfiring into the airbox is a sign of an overly lean mixture. The fuel in the cylinder is still burning when the intake valve opens and it fires off the new charge. Check for air leaks anywhere in the intake system. The problem gets worse in winter due to the fact that cold air is more dense making the lean condition worse.

Mad