Loss of power prior to stalling. Suggestions?

[s2kenny]

Hey guys. I'm having some trouble with my bike recently and I want to get your opinion on what might be wrong.

2008 Ninja 250r
3 #4 washers under each shim
UNI air filter - Removed snorkle
Full Area P replica exhaust
Kleen air system plugged

3 times my bike stalled on me. This was after removing the Kleen air system, Putting washers in, and removing the gas tank for a paint job.

I will be riding along and the usually smooth exhaust sound starts to burble. It goes from a smooth vrooooooommm to a vroomroomromroom and I start to lose power. I find myself putting more throttle just to stay at the same speed, and then in about 15 seconds after the loss of power starts my bike stalls completely.

I pull over, try to start it and it doesn't budge. After about 10x of 5 seconds bursts of holding the starter, it finally starts. Rev it a few times and it seems normal. Burble is gone. Power has returned.

Any Ideas of what could be wrong?

- Debris getting into the fuel?
- Bad shimming job?
- Messed up removing the Kleen air system?

Thank !!

[kkim]

next time that happens, try popping the gas cap open and see if the bike starts after that. could be a blocked air vent for the fuel tank.

[s2kenny]

Hmm that's a good idea. I spray painted my gas cap so I could have maybe clogged it up.

Kkim don't you ever sleep?? Thanks for the help again.

[demp]

sounds just like when I ran outa gas that one time, I would expect he's right

[dubojr1]

Take a look at these. I don't think a solution has been determined yet. Both my 08 & 09 do this occasionaly. I believe it has something to do with the tank venting.

http://www.ninjette.org/forums/showt...&highlight=cdi

http://www.ninjette.org/forums/showt...&highlight=cdi

[bob706]

+1 for tank venting

[DAKINECHICk]

Does it sit outside in HEAT? The gas turning to vapor from the sitting in the heat can cause your bike to do exactly that. Just my 2 cents.

[CZroe]

Originally Posted by s2kenny

Hmm that's a good idea. I spray painted my gas cap so I could have maybe clogged it up.

Kkim don't you ever sleep?? Thanks for the help again.

Hawaii is two hours earlier and he's retired.

Anyway, I have had this happen numerous times on a completely stock bike. Usually, it happens when I run it hard after a cooling event (rain or 8-20 minute cool down after full warm up). We've been discussing it in other threads, but no solid confirmation/diagnosis yet. dubojr1 just recently had it happen on his with an in-line fuel filter and confirmed that the engine gets no gas when this occurs, so now we are getting somewhere.

[dubojr1]

Alex... Should we merge these?

[Alex]

I'm OK keeping these separate. If people are having problems with their bikes and there isn't a clear solution, it's not clear if the problems they are having are actually the same anyway. It might be linked to the other threads, but it may not as well.

I do think this one is related to tank venting, though...

[dubojr1]

Ok... I see your point and would have to agree.

[ztrack157]

The bike wouldn't roll after it stalled? If the rpms started to decrease even when applying more throttle. There is a chance your rear brake could have been dragging.

This is probably not the case but you never know.

[CZroe]

Originally Posted by Alex

I'm OK keeping these separate. If people are having problems with their bikes and there isn't a clear solution, it's not clear if the problems they are having are actually the same anyway. It might be linked to the other threads, but it may not as well.

I do think this one is related to tank venting, though...

Plus, most of the discussion has happened in a thread with a misleading title (still fingers the CDI, which we doubt).

[dubojr1]

Originally Posted by CZroe

Plus, most of the discussion has happened in a thread with a misleading title (still fingers the CDI, which we doubt).

That is true. Which thread SHOULD we post updates to? It is not the CDI, I have a new BRT TIS.

[CZroe]

Originally Posted by dubojr1

That is true. Which thread SHOULD we post updates to? It is not the CDI, I have a new BRT TIS.

Perhaps Alex should edit that one's title do be more descriptive... like, instead of "Strange Problem, Overheated CDI?," something more like "Strange stalling problem; CDI? Fuel delivery?"

[kkim]

merge the threads for what???

we haven't even figured out what the problem is with his bike yet and you guys are assuming you know the answer even before it's even fixed?

I agree with Alex, leave the thread alone so we can figure out what's wrong with the bike instead of confusing the issue with something that may not be his problem at all.

[dubojr1]

Originally Posted by kkim

merge the threads for what???

we haven't even figured out what the problem is with his bike yet and you guys are assuming you know the answer even before it's even fixed?

I agree with Alex, leave the thread alone so we can figure out what's wrong with the bike instead of confusing the issue with something that may not be his problem at all.

Well how about CZroe's idea. I don't want to continuing posting updates in the other thread when maybe the results should be here. I also don't want the people that may have been following the other thread to loose out on the information if it is posted here. I'm open for suggestions. HELP!

[CZroe]

Originally Posted by kkim

merge the threads for what???

we haven't even figured out what the problem is with his bike yet and you guys are assuming you know the answer even before it's even fixed?

I agree with Alex, leave the thread alone so we can figure out what's wrong with the bike instead of confusing the issue with something that may not be his problem at all.

We aren't talking about merging. Just editing the other thread's title to make it easier to find the relevant discussion for those with a similar or identical issue. The way it currently is, anyone searching for a thread related to their issue will likely dismiss it because A) It doesn't mention stalling when the OP WAS talking about a stall and B) It mentions the CDI, which was a premature accusation that most searchers are unlikely to have considered. My old "bad gas?" threads on a few forums have the same problems but the discussion never got as far.

[kkim]

Originally Posted by dubojr1

Alex... Should we merge these?

Originally Posted by CZroe

We aren't talking about merging. Just editing the other thread's title to make it easier to find the relevant discussion for those with a similar or identical issue. The way it currently is, anyone searching for a thread related to their issue will likely dismiss it because A) It doesn't mention stalling when the OP WAS talking about a stall and B) It mentions the CDI, which was a premature accusation that most searchers are unlikely to have considered. My old "bad gas?" threads on a few forums have the same problems but the discussion never got as far.

huh?? stopping hijacking the OP's thread.

[WindMeUp]

Don't forget about the small inline fuel filter at the inlet of the carb???

Part #49019 in this photo

http://images.powersportsnetwork.com...1527_E1611.jpg

[s2kenny]

I'll give the gas cap thing a try. Is there any chance I could have clogged it up when I spray painted the cap black? I never had this problem before I removed the tank for the paint job and painted the cap at the same time.

It rolled fine, rear brake isn't an issue.

[s2kenny]

Originally Posted by WindMeUp

Don't forget about the small inline fuel filter at the inlet of the carb???

Part #49019 in this photo

http://images.powersportsnetwork.com...1527_E1611.jpg

Never knew that was there, I'll try to clear it out next time I get my fairings off.

[s2kenny]

Originally Posted by DAKINECHICk

Does it sit outside in HEAT? The gas turning to vapor from the sitting in the heat can cause your bike to do exactly that. Just my 2 cents.

Not really, both times were at midnight. Thanks though

[CZroe]

Originally Posted by kkim

huh?? stopping hijacking the OP's thread.

It's not hijacking when it's relevant. Are we supposed to make ANOTHER thread in which to discuss this thread and compare it with the CDI one and any more that may pop up in the future? The ONLY difference in his description here is that it's not remotely stock and it doesn't seem to take as long for him to start it up again without opening the tank.

Originally Posted by s2kenny

I'll give the gas cap thing a try. Is there any chance I could have clogged it up when I spray painted the cap black? I never had this problem before I removed the tank for the paint job and painted the cap at the same time.

It rolled fine, rear brake isn't an issue.

Well, if it is the same problem, a few of us are having it without having painted anything. Of course, paint can clog holes like debris, and there may be dust or something clogging mine after many thousands of miles.

Originally Posted by s2kenny

Not really, both times were at midnight. Thanks though

It seems that operational heat is all that is required. Cooler external temps may, in fact, be what trigger it (sudden cooling from rain or short cool down before running hard again). When it cools, I think that the tank develops a vacume faster than it can vent and, thus, fuel delivery stops until pressure nearly equalizes again.

[kkim]

Originally Posted by CZroe

It's not hijacking when it's relevant. Are we supposed to make ANOTHER thread in which to discuss this thread and compare it with the CDI one and any more that may pop up in the future? The ONLY difference in his description here is that it's not remotely stock and it doesn't seem to take as long for him to start it up again without opening the tank.



Well, if it is the same problem, a few of us are having it without having painted anything. Of course, paint can clog holes like debris, and there may be dust or something clogging mine after many thousands of miles.

this...

Originally Posted by s2kenny

3 times my bike stalled on me. This was after removing the Kleen air system, Putting washers in, and removing the gas tank for a paint job.

My troubleshooting experience has led me to investigate the last thing that you did before a problem starts. Many times it's something that was done recently that causes the problem.

Sending him off to investigate a possible CDI problem, when it is most likely not, is just a waste of time at this point. While there is a very slim chance of it being the problem, there are easier, more productive, conclusive options he should be looking at before concluding a faulty CDI as his problem... a problem that you guys can't even confirm/fix even after months of head scratching.

If it does prove to be a CDI problem, then yes, I agree that a simple post in the other thread linking others here will help, but until it is proved to be a CDI problem, let the guy fix his bike.

[dubojr1]

Originally Posted by s2kenny

I will be riding along and the usually smooth exhaust sound starts to burble. It goes from a smooth vrooooooommm to a vroomroomromroom and I start to lose power. I find myself putting more throttle just to stay at the same speed, and then in about 15 seconds after the loss of power starts my bike stalls completely.

I pull over, try to start it and it doesn't budge. After about 10x of 5 seconds bursts of holding the starter, it finally starts. Rev it a few times and it seems normal. Burble is gone. Power has returned.

Any Ideas of what could be wrong?

But kkim his problem he is describing above IS identical to what is happening to us guys in the other thread.
We know now that it is NOT the CDI and are not trying to lead him in the wrong direction. The other thread is where the "trial and error" problem solving is happening with current updates. The 'Bad CDI" thread has developed itself into a fuel issue. The same fuel issue s2kenny is describing. Maybe the solution IS to start a completly new thread.

[Alex]

Settle down, kiddies. I edited the title of the other thread to "strange problem, bike losing power then stalling". Neither that thread nor this thread have a conclusive fix, and it's not clear that it's even the same problem, so they are fine on their own. Anyone searching for "stalling" will now find them both anyway.

If I search on CDI, there are a whole bunch of threads about it, as well as an entry in our wiki:

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

Largest CDI thread:

http://www.ninjette.org/forums/showthread.php?t=21043

[wyckedflesh]

It has been reported that some of the smaller magnetic tank bags that have a smooth rubber bottom are doing a great job of blocking the venting at the cap on a variety of carbed bikes. (Sportrider,Motorcyclist,Cycle World, not sure which in the tech question section, issues are at work so I don't have them here.)

I also had a problem when I did the carb work of pinching one of the vacuum lines from the carb to the pump/fuel tap. This reduced the amount of vacuum to work the diaphram enough that it would run out of enough fuel in the float bowls to keep the bike running.

[dubojr1]

Originally Posted by wyckedflesh

It has been reported that some of the smaller magnetic tank bags that have a smooth rubber bottom are doing a great job of blocking the venting at the cap on a variety of carbed bikes. (Sportrider,Motorcyclist,Cycle World, not sure which in the tech question section, issues are at work so I don't have them here.)

I also had a problem when I did the carb work of pinching one of the vacuum lines from the carb to the pump/fuel tap. This reduced the amount of vacuum to work the diaphram enough that it would run out of enough fuel in the float bowls to keep the bike running.

I don't have a tank bag yet and I'll make it a point to check my vacuum lines.

[CZroe]

Originally Posted by kkim

My troubleshooting experience has led me to investigate the last thing that you did before a problem starts. Many times it's something that was done recently that causes the problem.

Sending him off to investigate a possible CDI problem, when it is most likely not, is just a waste of time at this point. While there is a very slim chance of it being the problem, there are easier, more productive, conclusive options he should be looking at before concluding a faulty CDI as his problem... a problem that you guys can't even confirm/fix even after months of head scratching.

If it does prove to be a CDI problem, then yes, I agree that a simple post in the other thread linking others here will help, but until it is proved to be a CDI problem, let the guy fix his bike.

Even in that thread, no one suspects the CDI. The OP just never changed the title. That's what our issue with the title of that thread was. s2kenny is describing a stall that is exactly how I and others have experienced. We aren't going to get any closer if we can't identify the same issue where it exists so that we can put our heads together!

Yes, you are right about proper troubleshooting technique, but the conclusion here is that it is likely a venting problem which his recently painted cap may have exascerbated. That doesn't make it a different issue, per se. Same as my 15,000 miles of dusty debris and a tank bag are exascerbating factors in mine.

Originally Posted by Alex

Settle down, kiddies. I edited the title of the other thread to "strange problem, bike losing power then stalling". Neither that thread nor this thread have a conclusive fix, and it's not clear that it's even the same problem, so they are fine on their own. Anyone searching for "stalling" will now find them both anyway.

Thanks, Alex!

Originally Posted by Alex

If I search on CDI, there are a whole bunch of threads about it, as well as an entry in our wiki:

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

Largest CDI thread:

http://www.ninjette.org/forums/showthread.php?t=21043

Yeah, thanks, but we now know that it's not related to that. "CDI" was a red-herring that threw everyone off for a while, but it's not it and pointing out the other thread's misleading title is the only reason it's even being uttered. We just wanted to point to the thread, NOT the CDI.

Originally Posted by wyckedflesh

It has been reported that some of the smaller magnetic tank bags that have a smooth rubber bottom are doing a great job of blocking the venting at the cap on a variety of carbed bikes. (Sportrider,Motorcyclist,Cycle World, not sure which in the tech question section, issues are at work so I don't have them here.)

I also had a problem when I did the carb work of pinching one of the vacuum lines from the carb to the pump/fuel tap. This reduced the amount of vacuum to work the diaphram enough that it would run out of enough fuel in the float bowls to keep the bike running.

I almost always have a tank bag but I'm pretty sure that it has happened once or twice without. I haven't read my last two issues of Sport Rider. If anything is kinked on mine, the dealer is to blame. Good call. It's something to check out for the DIYers.

[s2kenny]

Thanks for everyone's responses.

I'm fairly certain it's a fuel related issue.

Here is a pattern I just realized.

Ride 1: 11pm at night.
-Started our ride and went for about 40 minutes riding fairly hard.
-Took a break for about 10 minutes at the end of a street and turned the bikes off.
-Started the bikes up again just fine and headed down the highway.
-5 minutes later the bike started bogging going uphill on the highway.
-Stalled, and restarted.

Ride 2: 12pm at night
-Started for a ride and went for about an hour
-Pulled over and took a break for 10 minutes
-Started right up and turned around to head back
-5 minutes later I started to bog
-Stalled and then restarted
-Rode for 30 minutes just fine
-Pulled over and took another 10 minutes break
-5 minutes later I started to bog
-Stalled and restarted


So it seems that whenever I go for a long ride, take a break, and start up again to push the engine. I get the stall condition.

[kkim]

have you tried popping gas cap to see if that fixed the problem? take your extra key, ride with it inserted in the gas cap and when the bike starts to stall, pop open the cap and see if that stops the stalling.

[ninjabadger]

I would like to add another data point in favor of a tank venting problem. This sounds identical to the problem I posted about two weeks ago and I believe I successfully narrowed it down to the rubber pad on my tank bag preventing the tank from venting which would cause me to stall out in the manner described in the original post after riding a while. Cracking the tank quickly got me back up and running, and periodically breaking the seal between the bag and the tank while riding also seemed to work, albeit with a bit more peril involved.

[s2kenny]

Originally Posted by kkim

have you tried popping gas cap to see if that fixed the problem? take your extra key, ride with it inserted in the gas cap and when the bike starts to stall, pop open the cap and see if that stops the stalling.

Haven't had the bike stall on me again yet. I'll leave the key in next time the conditions are setup again for a stall (Ride, break, ride)

[s2kenny]

Originally Posted by ninjabadger

I would like to add another data point in favor of a tank venting problem. This sounds identical to the problem I posted about two weeks ago and I believe I successfully narrowed it down to the rubber pad on my tank bag preventing the tank from venting which would cause me to stall out in the manner described in the original post after riding a while. Cracking the tank quickly got me back up and running, and periodically breaking the seal between the bag and the tank while riding also seemed to work, albeit with a bit more peril involved.

Sounds like another +1 for fuel cap venting. I don't have a tank bag but I do have that layer of paint.

[s2kenny]

So the verdict is... It's the GAS CAP!

I have taken a few more rides with situations setup for fuel starvation due to a vacuum in the fuel tank. And prior to riding I opened the gas cap to hear a rush of air suck into the tank. I haven't had a problem since I started opening the gas cap before riding.

I think I'm going to try to thin out my cap with paint thinner or just replace it with a stock one.

[demp]

Remind me to never paint my gas cap, glad you found the answer though

[dubojr1]

My cap is not painted on either of my bikes. Problem still remains.

[s2kenny]

Maybe you somehow have debris in the vent lines?

[CZroe]

Originally Posted by s2kenny

Maybe you somehow have debris in the vent lines?

Maybe I do too.