Explosion when starting?

[supahamster]

Scared the bejesus out of me a few times, but on rare occasions my bike shoots out an explosion upon starting (like a gunshot... no joke). Any idea what might be causing this to happen? On both occasions, it happened on a cold start. The bike runs perfectly with no funny performance/mechanical issues. Any ideas what might be causing this to happen?

I have a california bike (with the Kleen system). The only mods I have on my bike is a Yoshimura exhaust. Thanks in advance!

[sofo]

I've gotten this a couple of times. Curious to know what it is myself.

[Cuongism]

Wow, this actually happened to me too today! I believe the two types of backfire are intake and exhaust. Causes are generally dirty gas, dirty carbs or bike running too rich. Mine was from the exhaust and it was from my bike running rich. Some jerk put my choke on about halfway so I didn't notice until I got home which is about 8 miles mostly highway. My idle was at 1700 which is too high especially since I never used the choke. I guess I have to add checking the choke as part of my pre-ride routine.
Does your bike backfire when riding or only when starting?

[supahamster]

Originally Posted by sofo

I've gotten this a couple of times. Curious to know what it is myself.

i'm assuming you don't have a california bike?

i always warm up the bike to at least 120-130F before riding w/ the choke on cold starts. the bike backfires pretty frequently when i let off the throttle slowly - from what i hear, it's the "kleen" system that causes this.

[Cuongism]

You can always remove the "Kleen" system.
http://www.ninjette.org/forums/showthread.php?t=9948
If you have a yoshi full system, you should probably remove it since you wont have any cat converters to deal with.

[sofo]

Originally Posted by supahamster

i'm assuming you don't have a california bike?

i always warm up the bike to at least 120-130F before riding w/ the choke on cold starts. the bike backfires pretty frequently when i let off the throttle slowly - from what i hear, it's the "kleen" system that causes this.

It is a Canadian market bike. No kleen system on mine, and I still have stock exhaust, intake, and jetting.

[lockie]

Happens to most of us.
Check out http://www.ninjette.org/forums/showt...light=backfire

[g21-30]

Originally Posted by supahamster

Scared the bejesus out of me a few times, but on rare occasions my bike shoots out an explosion upon starting (like a gunshot... no joke). Any idea what might be causing this to happen? On both occasions, it happened on a cold start. The bike runs perfectly with no funny performance/mechanical issues. Any ideas what might be causing this to happen?

I have a california bike (with the Kleen system). The only mods I have on my bike is a Yoshimura exhaust. Thanks in advance!

It's just glad to see you! Kind of like the gas tank singing, after you've been riding a while.

[dubojr1]

Originally Posted by drsketch

it's called a backfire, did it once loud at startup when I didnt ride it for 3 days to due severe storms(I think it was mad at me), and it has little popswhen I am slowing down but thats normal

Little pops when slowing is not normal...

If you have added exhaust, the pops can be elimanated by removing the Kleen air system.

[dubojr1]

Originally Posted by drsketch

maybe pops is exaggerating, maybe little rumbles, hard to explain, not backfire pops though

and I am not in california so not sure if I have that

All the 250's have them. Both of my bikes had them stock.

Yeah I know the sound your trying to describe. Little rumbles is a good way to put it. My stopped after removing the KAS.

[dubojr1]

Originally Posted by drsketch

PA is an inspection state, will it pass inspection with this removed? Also do you have the pros and cons to keeping/removing this?

This might explain my gas mileage if that thing is putting that much of a damper on air flow.

Hmmm.... I'm really not sure if it will pass inspection...

It doesn't have anything to do with air flow. Have a read of this thread. Great information.

http://www.ninjette.org/forums/showthread.php?t=9948

[kkim]

Originally Posted by sofo

It is a Canadian market bike. No kleen system on mine, and I still have stock exhaust, intake, and jetting.

I believe all +08 250 ninjas sold in the North American market have the Kleen System.

[Alex]

http://www.ninjette.org/wiki/My_Bike_Backfires

[sofo]

Originally Posted by kkim

I believe all +08 250 ninjas sold in the North American market have the Kleen System.

Oh yeah? Hmm... I'll double check, you are usually (read: always) right Kelly.

I thought it was just a Governator state thing.

[00NissanNinja]

I think you guys are thinking about the evaporative emissions canister, that is CA specific.