PDA

View Full Version : Backfire and Engine Light



kalali
07-14-2008, 02:53 PM
While riding my '00 X1, the engine backfired a couple of times on separate occasions and each time the engine light came on momentarily. Otherwise the bike ran just fine. The bike is stock with the exception of a V&H slip-on exhaust. I was wondering what could be causing this...
Does the ECM require tweaking with a V&H slip-on? Not sure if the pevious owner did aanything with the ECM after he put the V&H on the bike.
Thanks in advance for your help.

LeFox
07-14-2008, 04:12 PM
since when does the bike have the problem?
does it occur when the engine is warm, cold, both?
any other mods except for the v&h?

kalali
07-15-2008, 02:32 PM
LeFox,
Thanks for the reply. The backfire/engine light combo only happened two or three times and all during a single ride and it wasn't a real loud backfire - just a louder then usual popping sound. The motor was warm at the time. I do get a little popping at decceleration when the motor is cold but it goes away once warmed up. That must be normal.
As for other engine related mods, I am not aware of any. I did put in a measured amount of Techron FI cleaner when I filled up after my ride (which had the backfire) and I rode it this morning. It runs perfectly now. As it does 99.9% of the time. My only concern is if the backfire could somehow result in the motor to stall and get stranded somewhere. Does changing to the V&H slip-on require ECM tweaking? Not sure if the revious owner did that. Thanks again.
May be I should just put the stock exhaust back on..
Just as an aside, does sthe V&H add anything other than the throaty note, i.e., perfornamce gain, etc.?

LeFox
07-15-2008, 08:31 PM
ok, now we're talking.

the backfire is most likely a result the ecm learning, ignition timing, which most likely resulted in a early burn or a bit of fuel pre-igniting in the intake.

aslong as you don't add an better airfilter you could get away with the slip-on, but you will be running a tad on the lean side.
i would recommend ecm tweaking...maybe browse ebay for an race ecm or remap your current. it not only gives you a richer mixture, it also gets your redline up to about 6800rpm
the x1 race ecm goes around 350€ new :o

without other tweaks, a slip-on will give you about a 2hp gain...nothing major, but the sound :D

kalali
07-16-2008, 03:22 PM
LeFox,

Thanks for taking the time to reply.
To be honest, the bike in stock form has more power/torque than I would ever fully use so I am really not after much performance improvements. I do like the V&H sound but if is going to make the bike "unhappy" I will put the stock exhaust back on. Before I do that, could the choice of the spark plug (or plug gap) help in making the mixture a little richer?
Thanks again.

LeFox
07-16-2008, 08:32 PM
well tweaking the engine is actually a look for performance, but it's letter your engine run smooth & healthy...added performance is a bonus result of that smoother, healthier engine ;)

no, the sparkplug isn't something that will make your mixture richer, it will make the 'explosion' better.

what i would suggest is leave the v&h on, go for a ecm reset (not expensive) and make sure you run in closed loop (http://en.wikipedia.org/wiki/Control_theory#An_example) for about 15 minutes @ about 3000rpm ;)

kalali
07-17-2008, 01:20 PM
Thanks again.
Is this ECM reset something done by the dealer?
So now if I switch back to stock exhaust will A/F go back to normal/factory settings and everything will be OK or the ECM has to "relearn" the factory settings?
Appreciate it.

FIDOSOL
07-17-2008, 01:38 PM
Just wanted to piggyback on your topic.

Okay, so today I was doing the no-no with a cbr600 and by no-no i mean rippin' it hard. Well going from 1st to 2nd my bike backfired through the airbox, startled me for sure, never had that happen before...any ideas? Oh and I ride 'aggressively' all the time, so the bike is used to it...

LeFox
07-17-2008, 01:48 PM
Thanks again.
Is this ECM reset something done by the dealer?
So now if I switch back to stock exhaust will A/F go back to normal/factory settings and everything will be OK or the ECM has to "relearn" the factory settings?
Appreciate it.
you, it's done by the dealer, or if you have direct-link or ecmspy, you can do it yourself.
settings are stored, so if you're just switch without a reset in between you should be fine. if you experience trouble, unsmooth accel, etc...that is when you're in need of a reset.


Just wanted to piggyback on your topic.

Okay, so today I was doing the no-no with a cbr600 and by no-no i mean rippin' it hard. Well going from 1st to 2nd my bike backfired through the airbox, startled me for sure, never had that happen before...any ideas? Oh and I ride 'aggressively' all the time, so the bike is used to it...
tuber-part of the forum, fido ;)
was the bike cold, warm, hot?
outside temp?
mileage?

FIDOSOL
07-18-2008, 12:24 AM
hmm....bike was already warmed up, it's like 90 degrees outside, and i have around 2300 miles on it.

LeFox
07-18-2008, 09:15 AM
any aftermarket parts on it?
has your tps been reset?
does your engine idle at variable rpm?
with that pop, do you lose power and then get it back resulting in a kick in the butt?

kalali
07-18-2008, 03:23 PM
Seems like FIDOSOL is in the wrong forum asking about Honda CBR600!
BTW, my backfire was from the exhaust not air box...

Anyway...

LeFox,

As for the ecmspy tool, unfortunately I am not really a "techy" person and while there appears to be a lot of information available about this software, I am afraid to dive in and possibly screw something up. At this point I just want to solve this specific issue and if switching back to the stock exhaust solves the problem, I will go that route. The V&H sound is actually a mixed blessing and I am sure my wife and neighbors will be happy is I switched the exhaust. Now, since I never rode the bike with the stock exhaust, will I really be diappointed with the performance loss if/when I switch to stock? A 2hp loss/gain does not sound that significant...
Thanks again for all your input.

LeFox
07-18-2008, 05:32 PM
Seems like FIDOSOL is in the wrong forum asking about Honda CBR600!
fido isn't asking about a crb600, he was talking about his experience vs. a cbr600.

for you, if the you don't experience the backfires and the bike runs smooth and is reacting good the the throttle...there should be no real problem.
if you're not going to do alot of tuning, i wouldn't go and get ecmspy and the cables just for that 1 reset.
if you don't want to risk anything, go back to the stock.

FIDOSOL
07-18-2008, 08:36 PM
I'm completely stock except for the white wire mod, and the breather re-route. So nothing major...hasn't happened since, and yea, little loss of power, and then a slight kick. Did I break it?

LeFox
07-18-2008, 09:02 PM
I'm completely stock except for the white wire mod, and the breather re-route. So nothing major...hasn't happened since, and yea, little loss of power, and then a slight kick. Did I break it?
nah, you didn't brake it...atleast not yet anyway :p
did you get a reset after the breather re-route?

you might want to get your AF checked, cause it could be a leaky inlet gasket. if that is the case, you would experience slight powerchanges during steady constant throttle position.

could also be your ignition, mainly the plugs.
i would say, upgrade your plugs...it's cheap and you can do it yourself.
no result => get your AF checked => value 100 => tps reset.

FIDOSOL
07-18-2008, 09:04 PM
hmm, is that necessary? only happened once, besides, I am not allowed to get anything for my bike right now...childcare is expensive..and the wife is scary...[sad]

LeFox
07-19-2008, 06:23 AM
hmm, is that necessary?
well i'm not placing a gun to your head [smirk]
you could have said before that it only happened once, though...could have just been a bit of dirt in the fuel line aswell :o

FIDOSOL
07-19-2008, 12:10 PM
Well going from 1st to 2nd my bike backfired through the airbox, startled me for sure, never had that happen before...any ideas?

I did say it only happened once.

Thank you LeFox for your advice.

LeFox
07-19-2008, 12:30 PM
nope, you said it never happend...never said it's not happening anymore :D

but anyway...if you're having no more backfires and the bike still puts a big grin on your face, i'm happy ;)

FIDOSOL
07-19-2008, 10:11 PM
Once again, like every other time on this forum (and your job too probably), you are correct, Oh and it hasn't done it since, and thank you.

kalali
07-21-2008, 04:44 PM
Lefox,

"....if you don't want to risk anything, go back to the stock...."

Well, I went ahead and put the stock muffler back on this weekend. I rode the bike yesterday and this morning to work and the decel popping and backfire all disappeared. Or may be I just can't hear them any longer!! The acceleration also feels more linear even with a semi cold motor. So, all in all, it looks like a good move except the bike does feel to have lost a little oomph, but not much. And needles to say, my wife and neighbors all seem to approve the switch! I will keep it this way until I find someone in the area who could help me with the tuning. My main issue now is a leak in the gasket between the starter and the primay. Looks like a lot of work to remove a lot of pieces to get to the gasket. Omce again, thanks for all your input.

LeFox
07-21-2008, 09:03 PM
no problem, kalali.

just on a sidenote, a little decel popping is normal with an open exhaust, but the backfire shouldn't be happening.

kalali
07-28-2008, 05:42 PM
Well, after riding with the stock exhaust for a week or so I have realized I really miss the V&H sound and the extra oomph.
So I opened the backplate of the V&H to see what is inside..Well, no baffle and no packing material, just a hollow can!
The previous owner must have thought removing the baffle/packing would help with performance but on the contrary (according to the V&H folks) it hurts the performance just makes the exhaust louder.
I went ahead and ordered the baffle and the packng from V&H and I am hoping that with the baffle and the packing the mixture will not be quite as lean and I should be able to "teach" the ECM to work and hopefully the occasional backfires will not happen again...
LeFox, what do you think?

teh Nub
07-28-2008, 08:07 PM
Back to FIDO's air box backfire, I have had a few airbox back fires occur on my XB12Ss when the bike is cold, usually when slowing down and and bliping the throttle. I first noticed this after resetting my TPS for the first time and leaving idle adjustment at 4.6 deg and 5.1% as the ecmspy states in the tuning manual (idle is right at 800 rpm give or take). The idle was probably a few hundred rpm above that when I took ownership of the bike. I have since done the white wire mod and crankcase/cylinder vent to airbox delete mod, fallowed by another TPS reset and AFV reset. Previous AFV was 105. Bike is stock with the exception of the previous mentioned items... Enough rambling for now....

LeFox
07-28-2008, 11:36 PM
LeFox, what do you think?
well, personally i would not add the baffle, but...it's your choice.

the packing is good though, that will deffinatly help with the backfires.
but about running to lean...except for remap, nothing will change the mixture like it should do.

but it will run...

kalali
07-29-2008, 01:33 PM
LeFox, as always thanks for the quick response.
My understanding was that the packing actually "wraps" around (or slides over) the baffle and without the baffle (which is essentially just a long tube) I wouldn't be able to use the packing. I will see when I recieve them in a couple of days...

LeFox
07-29-2008, 02:54 PM
oh ok...i thought you ment a baffle to have lesser noise (smaller insert), not the interior one :o

yea, you need to bigger punctured pipe for the interior.

BuellS1Culver
08-05-2008, 11:59 PM
I had the same problem with my bike when i first got it. (1996 S1). A backfire is when one of two things happens, 1: you have to much air in the air-fuel mix
2: you have an exhaust leak, ex. air is escaping before leaving the muffler.
The engine light on my bike did not go off, but being a first year model, it doesn't have a computer in it. Always remember to cheek the basics and !!ALWAYS!! but !!GOOD!! fuel in your bike!

kalali
08-06-2008, 06:41 PM
Quick update. I went ahead and ordered the baffle and the packing and put it all together abd back on the bike. After a couple of days of riding including the steady 3000+ RPM for 15-20 minutes to get the closed loop learning out of the way, it looks like the backfire issue has been resolved. I still do get a little decel pop but it is in the normal range. It looks like taking the baffle/packing out pushed the mixture too much into the lean zone for the ECM to compensate. I will see how it goes but so far I am a happy camper.

LeFox
08-06-2008, 08:33 PM
[up]

good for you!

now you can enjoy the buell symphony while riding :D