Backfire at Startup!!!!!!

[shadow]

had mine before my second ride on the bike, but knew exactly what it was. happened with no helmet or ear protection, in an open indoors garage with the tail facing the inner wall. Sadly I can't say i was devirginized as I used to go shooting frequently, and didn't always wear protection. Guess it was more of an "Oh, well good morning to you too sweetie!"

[bostonmichelle]

As suggested in this or some other forum, I've been letting it idle for a minute before turning it off, and I haven't had a boom since. I'm not saying that this is the cure, but it's working for me so far.



***EDIT 9/15/09*** I JINXED MYSELF! Just this morning, the morning after I wrote the above note, it "backfired" again! Forget about idling it before turning it off. It doesn't work!! Sigh.

[g21-30]

Welcome to the "Club" Joe and Michelle! Mine hasn't done it, since I retrofitted the '88-94 CDI, but it probably will, now that I mentioned it!

My gas tank still whistles and my grand kids love that when they hear it.

[kkim]

Originally Posted by bostonmichelle

As suggested in this or some other forum, I've been letting it idle for a minute before turning it off, and I haven't had a boom since. I'm not saying that this is the cure, but it's working for me so far.



***EDIT 9/15/09*** I JINXED MYSELF! Just this morning, the morning after I wrote the above note, it "backfired" again! Forget about idling it before turning it off. It doesn't work!! Sigh.

lol

[bostonmichelle]

I just got saddle bags, tank bag, and tail bag for the Ninja as we're planning a big Christmas/New Years trip to San Fran from LA. I got the saddle bags on Saturday & promptly went out to try them on. I hadn't ridden the bike since Friday, but for some reason, while I was putting on the bags, my little girl started making little sighs! It was so funny that I started talking to her about the trip! I think she's excited!

Note to self: do not admit talking to motorcycle on public forums!

[g21-30]

You had me going there for a minute, when you said you were talking to your little girl! It's time for me to leave work...went right over my head.

[noche_caliente]

Originally Posted by bostonmichelle

I just got saddle bags, tank bag, and tail bag for the Ninja as we're planning a big Christmas/New Years trip to San Fran from LA. I got the saddle bags on Saturday & promptly went out to try them on. I hadn't ridden the bike since Friday, but for some reason, while I was putting on the bags, my little girl started making little sighs! It was so funny that I started talking to her about the trip! I think she's excited!

Note to self: do not admit talking to motorcycle on public forums!

Don't worry - I talk to mine too - she gets very excited when we get ready to go somewhere and very upset when she sees me getting in the cage... my son even asks "mommy, why your motorcycle crying? she want you to ride her?"

[bostonmichelle]

Originally Posted by noche_caliente

Don't worry - I talk to mine too - she gets very excited when we get ready to go somewhere and very upset when she sees me getting in the cage... my son even asks "mommy, why your motorcycle crying? she want you to ride her?"

That's so cute!! And, thank you for the support!

[jupiter1827]

I have about 7k miles on my ninja now, but I have had this problem pretty much since I got her almost a year ago. I ride it to work everyday, and though it is embarrassing when I start it up and it does this, I never really thought too much about it... until today. There was a couple walking right behind me when I reached to start it up. Luckily I thought twice and waited until they walked by. After I started her up, bang!!! The lady turned around, and the look on her face... I think she thought someone fired a gun - I had to reassure her that it was just my motorcycle. Wow, I felt so bad.

I live in Hawaii, so there's no crazy change in temperatures, but it does rain a lot. Pretty much every day it rained/misted, I could bet that I would get that loud backfire sound, so I thought maybe water vapor got inside, and when the engine started up, the vapor expanded, and pow! However, I don't remember it raining today. I did read on a Harley forum that it could have something to do with the fuel mixture etc. I guess I'll take it to a shop and see what they say.

Sorry for the novel, but I thought it was kind of a funny story - after the lady recovered that is.

[kkim]

It's normal for these bikes. Don't worry about it.

Welcome to ninjette.

[g21-30]

Jen,

It's not unique to rainy/misty areas. It's just that the bike likes to express its opinion via backfire and/or singing via the gas tank!

[g21-30]

Two weeks to the day! My bike had a healthy backfire at startup this afternoon. Lady a few houses down was working in her flower garden. It gave her a pretty good startle, So much for the thought that the CDI retrofit fixed it! I knew I shouldn't have mentioned it.

[Samer]

My Ninja is completely stock. I have about 200 miles on it and last week was the first and only time the BANG occurred for me so far. This was of the shotgun variety and it scared the S*HIT out of me. Mainly because I completely didn't expect it. As someone already commented, I also prefer the whistling tank sound since that one is kinda cute.

[killerkay3]

Originally Posted by Samer

My Ninja is completely stock. I have about 200 miles on it and last week was the first and only time the BANG occurred for me so far. This was of the shotgun variety and it scared the S*HIT out of me. Mainly because I completely didn't expect it. As someone already commented, I also prefer the whistling tank sound since that one is kinda cute.

haha

[g21-30]

Originally Posted by Samer

My Ninja is completely stock. I have about 200 miles on it and last week was the first and only time the BANG occurred for me so far. This was of the shotgun variety and it scared the S*HIT out of me. Mainly because I completely didn't expect it. As someone already commented, I also prefer the whistling tank sound since that one is kinda cute.

You have now been initiated! Welcome to the club of "Backfires and Whistles!"

[overload]

Does this only occur in the carburated models ? Do the FI models also backfire ?

[Cedilla]

Mine has only backfired once when starting it up, I think it was because it had been sitting for a week. Also I had trying to get it started for about 30sec before it happened, then BOOM!!!!, then it started but, was hard to keep idling for a couple of min. Also my gas tank whines almost constantly, but it usually does it as somebody is walking up to it, I have to explain it to someone almost daily, but I don't mind.

[g21-30]

Originally Posted by overload

Does this only occur in the carburated models ? Do the FI models also backfire ?

Sorry, I don't know. If you have it happen, please post and let us know.

[athimmel]

Well, mine just lulled me into a sense of security after not doing it for a while. Then, this morning...KABOOM!! Just about destroyed two sets of eardrums. (Wasn't pulled out of the garage far enough!) Mine is stock, and has about 1200 miles. Third time for a major after/backfire. At first, I thought it was because I used mid-grade gas, so I went back to regular. A month or two later...the return of the boom. This morning was the first day riding after 2 days of rain. I always end up idling a bit before turning off the bike, because I thought it might burn off last bits of fuel. Nope.

I think the neighbors thought there was a murder on the streets. Sound like that in a quiet subdivision causes a lot of attention.

[RedCromwell]

My stock 2010 backfired the day after I got the 600 mile service done. Freaked me out and made wonder wth the dealership did.

Didn't do it again for awhile so I figured it was just a fluke... maybe moisture in the exhaust... then it happened again.

So, far it's probably happened about three times in total each time at first startup in the morning with no rhyme or reason.

After hearing others with the same experience I'm not concerned about it.

[Hitman]

Consider me in the "club". Mine did its bang at about 8AM and about 70 degrees as I started it. It was at about 250miles.

I did rev the throttle before I turned it off the night before. Damn that is loud. Luckily I had a heavy backpack on so my movement from the shock was minimal after I heard it.

[bdavison]

My neighbors dog has a habit of bounding up to the fence and woofing a low "Im gonna getcha" bark. Im used to it and just ignore him...

So anyway, the other day I pull my bike out, and hop on it, and here comes that dog...woof wooooooof woooof......






KAPOW!!!!!!!!!!!!!!!!!!!!!!!!!



Arf Arf Arf Arf Arf.


I almost dropped my bike I was laughing so hard.

[Jibs]

a normal occurence or not, does anyone have a way of preventing it from happening. My 08 will do it EVERY first startup of the day

[kkim]

have you tried not turning the throttle at start up?

plus, do you play with the throttle while the bike is off and parked between startings?

[Jibs]

hey kkmin,
No i dont play with the throttle on startup, and the throttle is not used when the bike is off.
With or without choke on startup is still happens. I aslo tried letting the bike idle before i shut it down.

[kkim]

has it always done this or is this something recent? I notice you have an 08... how many miles on it?

[Jibs]

my mistake its a 09, happened once between 0-700miles, but now at 800 miles its been happening during every first startup of the day after not riding it for at least 1-3 days. The only thing diff that i did was change the oil, but i dont think that could be causing it. Bike is stock also.

[kkim]

I agree... the oil change should not affect what is happening w/ the backfiring and popping on every cold start of the day does seem a bit excessive.

[Jibs]

That what I was thinking, any suggestions? Is there anything done on the first inspection that could cause/fix this?

[kkim]

Sorry, I can't think of any. The starting backfire is mostly an isolated/infrequent incident and even at that, people have not been able to find the real cause. That yours is happening on a regular basis has me stumped.

[Cuongism]

Interesting, I've had my 250 for about 1500 miles, a little over 2 months (currently at 7300 miles). For my first 1300 miles, it's never done this. However, after I changed my oil and filter it backfired twice the past two weeks. The other change I made was I stopped using the killswitch to shut off my bike. Before, I would kill the engine and then roll to park. Now I park with the engine running in neutral and then shut off the bike with the key after I parked (so it'll idle for a bit while I park).

[fuzion]

I have a 2009 Ninja 250. The backfire started happening around 2500 miles and still happens at roughly 3500 miles. I've had all the regular owner's maintenance performed as per the manual. I have stock exhaust, air filter, etc.

Since I'm in Canada the weather here is already quite cold at 2 degrees Celsius in the morning (35.6 degrees Fahrenheit).

What really baffles me is that on Tuesday, Wednesday, Thursday, and Friday it starts up just fine with no backfire. Almost every Monday after it has been sitting for 2 days I am almost guaranteed to get a backfire.

I have a short ride to work so I found that taking the highway instead of the scenic route seems to slightly reduce the occurrence of backfires but it does not get rid of it. I suspect that driving at higher speeds or for a longer time keeps the battery better charged. I also let it idle for 10+ seconds before shutting it off. I used to shut it off with the key but had too many backfires. For some reason, using the kill switch seems to result in slightly less backfires (but they're still there). I always use the choke to start it cold (otherwise it wouldn't start with this weather). Before it got cold I had backfires with and without the choke. Also I don't play with the throttle at all, each start is identical. The only difference is the 2+ days of not riding it.

Does anyone have any idea why leaving it sit for 2+ days seems to drastically increase the odds of getting a backfire on a cold start?

I don't understand why leaving it sit in a garage for 48+ hours would cause a backfire whereas leaving it sit in a garage for 10 hours would not cause a back fire. i.e. could the engine really get any colder after sitting for 10 hours?

Also, I've confirmed that flames come out the exhaust when it occurs. I always stare at the exhaust when I turn it on in the morning and if I start it before sunrise I'm sure to see a 12" flame shoot out the exhaust. It's a lot of fun and I could care less if I lived in the country, but since I live in the city and am surrounding by pain in the ass neighbors, I would prefer not to have the backfire.

Also, my garage is not heated. I wonder if I would get this if I had a heated garage.

Based on what I read, it seems like unburnt fuel is getting into the exhaust and is later being ignited when in the exhaust. Could there be something like condensation building up in the exhaust over 2+ days that could be causing this?

I've thought about rejetting or shimming but I don't see how that could fix the problem.

Could it have something to do with the battery? Could the battery be weaker after sitting for 48+ hours in cold air that it is causing a backfire? Would getting new spark plugs help?

[scotty]

I would like to make a note..

My bike did this also, but after I installed a full exhaust and removed the Kleen air system, it has not done it. I think it may have something to do with the Kleen air system on the bike. Im not 100% sure on this, but like I said, it hasnt happen to me since then. Can anyone who has taken off there Kleen air system agree to this?

[g21-30]

Originally Posted by scotty

Can anyone who has taken off there Kleen air system agree to this?

Nope! Still backfires, just louder with the full exhaust!

[lux]

First one this past weekend. Had my earplugs and helmet on already. hehe

[fuzion]

g21-30, did you also do the kleen air mod?
scotty, how long has it been since you did the kleen air mod?

I haven't had any backfires for a few weeks now as long as I take it out at least once for a good ride during the weekend.

Can anyone explain how the kleen air mod would prevent unburnt fuel from entering the exhaust (and causing the backfire)?

[g21-30]

Originally Posted by fuzion

g21-30, did you also do the kleen air mod?

Yes!

[scotty]

It has been a few months now. I havent had any back fire since. So my guess has been ruled wrong lol

[fuzion]

Thinking about winter storage again I just checked the user's manual for a refresher.

"Tie plastic bags over the mufflers to prevent moisture from entering."

Moisture in the muffler couldn't cause this could it? Maybe I should start tying plastic bags over the muffler during the weekend or maybe I should start spraying water in the muffler to see if that is causing the problem.

[g21-30]

^^^Moisture (water) is a byproduct of combustion. It's not going to cause backfire or prevent same.