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Discussion Starter #1
So I've seen a few people with issues similar to mine, but not exactly the same. When I go out to my bike in the morning, it starts up no problem. Occasionally, it will randomly just die. I will then have to start it again and it's fine. Sometimes as well, it will start and idle fine (this is the majority of the time), but when I go to take off it hiccups and sometimes stalls. So now, I usually blip the throttle as soon as I get it started, and I can feel the initial desire to choke out, but then it revs fine after that initial throttle blip. This as I said is a cold start from sitting overnight, so it's not vapor lock. This thing is fuel injected and has an automatic choke. I'm wondering if the choke is not closing fully? This also didn't seem to be such an issue during the colder months, so I'm again wondering about the choke not fully enriching the mixture and coupled with the warmer, leaner temperatures, I'm getting a stall. I'm also running BP fuel, and have tried several different gas stations all to the same result, so it's not the gas. Has anyone else experienced this on their first cold starts and having to blip the throttle?
 

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Discussion Starter #3
Did the first service myself. Have 2200 miles on her now. The idle speed is fine, it sits right at 1500 and never waivers. This tank I'm running some B12 through. MPG seems to have picked up from it, and the bike idles smoother. It may have just been a little gunky from the crappy winter blend gas around here, but it just "feels" like an initial mixture issue...if that makes any sense.
 

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Out of interest do you wait for the fuel system to prime before starting the engine? You can hear it buzz/whine a little when you power up the bike.
 

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Discussion Starter #5
Yep, sure do. Never start the bike until the whine stops and the gauges are done with their tests.
 

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Yeah I've noticed this too, I generally give it about 10+ seconds before I touch the throttle. I've been told by a mechanic that a lot of CBRs (not sure if this is pre-11 models or jut the new ones) come in to get their spark plugs replaced more than anything else. I assumed this was the reason for the "wanting to die" sound, and yes, just like you I have had the engine cut out when I rev it too early.
 

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Discussion Starter #7
Good to know I'm not alone in this. It doesn't do this EVERY TIME, but enough to notice with some frequency. My spark plug looked fine 1,000 miles ago, and I cleaned it and checked the gap, so I'm pretty sure it's not the plug. It runs absolutely like a scalded dog all times except right after cold start. I think this bike is just set up so incredibly lean from the factory that until the throttle is cracked open without dying the venturi effect gives it an issue compensating for the needed rich air to fuel ratio at initial start up. I don't think there's anything wrong with our bikes, but I was just wondering if it was common for other people to experience this at first start. Thanks for the replies guys, it puts an obsessive compulsive rider's mind at ease!
 

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I had a similar issue that cleared itself up after my first service. Maybe you should get it looked at by a professional? Just a thought. And it happened to me with, what seemed to be, "cold" starts too.
 

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Discussion Starter #9
There are no professionals around here. I'm a mechanic by trade, and the dealership that's close here I wouldn't trust with a moped. I am running a 5w-40 oil, which is slightly thicker, but at cold temps I wouldn't think it would cause the issue, as it's 5 weight. Maybe with a few more miles things will break in a bit more, because I don't ride this bike very hard. I really think that it may just have a little gunk in the injector, as the guy who had it before me thought it was a good idea to run racing gas instead of regular. He didn't ride the bike for weeks at a time, so I have a feeling it's gunked up race fuel. Will post back with results from a tank or two of running some B12. It's already smoothed out just from 100 miles with a few ounces mixed in.
 

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Sounds like that's the problem. After I put a few more miles on mine and ran more tanks of gas through it the problem cleared up. Hopefully that'll be the case for you as well! Good luck! Don't you just hate when you have second thoughts about buying used stuff because some people treat things weirdly/poorly? Some people can't have nice things...
 

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Discussion Starter #11
Yes, it's terrible. People still think the higher the octane, the better it is. He said that's all he ran in it. All I know is, when I siphoned what was left in the tank out when I brought it home, I had some residual left in the clear can I had it in after running it through my mower (don't care about it). And after about a week, it had turned a sickly brown color. Much exposure to air, and that race gas breaks down into a soggy mess. Thing is, it's got plenty of pep and I'm averaging 85 mpg, so I didn't think anything of it. Now I can only imagine what it's going to do after a thorough cleaning! Luckily, the guy only had it for 500 miles before I bought it off him, so he couldn't have done too much damage...I hope...I deserve something nice! :(

I'll report back after another tankful with B12 supplement.
 

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Yep, sure do. Never start the bike until the whine stops and the gauges are done with their tests.
Are you giving it enough warm up time before you start blipping the throttle? I let mine idle a minute or two before I even touch the throttle. From a cold engine start, I wait to see two bars on the temp gauge before riding off.
 

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Discussion Starter #13
No I don't do that due to wasting fuel. I'm fairly eco-minded. But on a fuel injected bike, you shouldn't have to wait at all for warmup. It should automatically richen up the mixture for a cold start to help with running and warmup times. Should be able to automatically twist the throttle and go. Although, like I said, 90% of the time this is the case. It's just occasionally it wants to hiccup at immediate rev or takeoff. My old GZ250 didn't even cut out on 23 degree mornings in the winter, and it was carburated and always ran lean. Just cap on full choke, she'd start and go every time without issue.
 

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Weird, never had such an issue before.

Compared to my old carbed Ninja 250 this bike is a dream in the cold weather.

Starts right up and works fine even in 18F weather.(I bought it in December)

Even in warmer weather the auto choke engages for the first few seconds. The bike can take throttle right away.
 

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I let mine warm up a little so that the oil is warm and flowing...but I make up for it because I am saving the world by running proper tire pressure.
 

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Discussion Starter #17
Yea, it's a little weird. There's no driveability problems with the bike, even when it is freezing cold. The ONLY problem is that initial throttle crack right after initial start. I wonder if the auto choke is getting hung or something, but I think that would trigger a DTC. I guess it's either that or the gunked up injector I suspect. Like I said, with the B12 it seems to be running better. I'm going to try to remember and tally when it does it and when it doesn't; that is, if it still does after this flush!:)
 

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No I don't do that due to wasting fuel. I'm fairly eco-minded

Paradoxically, you're wasting fuel if you DON'T let it warm up before riding. Like a lot of "green" ideas, there are unintended consequences.

Like you said, the system enriches the mixture to run the cold engine. You end up turning more rpms at the rich mixture while riding and so more total fuel than warming up at low rpms while a tiny amount of fuel is flowing.
 

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No I don't do that due to wasting fuel. I'm fairly eco-minded

Paradoxically, you're wasting fuel if you DON'T let it warm up before riding. Like a lot of "green" ideas, there are unintended consequences.

Like you said, the system enriches the mixture to run the cold engine. You end up turning more rpms at the rich mixture while riding and so more total fuel than warming up at low rpms while a tiny amount of fuel is flowing.
Agreed... I'll add that any engine, whether air cooled or liquid cooled, carbureted or EFI, should ALWAYS be given a short warm up period to allow the internal parts to heat and expand, before the motor is subjected to loading at RPM. Short changing you engine warm up time, to pinch a few pennies worth of fuel is just plain dumb. Sorry, but I have to call it like I see it. Still its your engine, treat it as you see fit.

Would you think that Formula One team's just fire up one of those engines and head out onto the track, and immediately put down hot laps, just because it has EFI, liquid cooling and engine management computers? Not a chance. They have a very specific engine start up protocol, including heat cycles, and stepped RPM cycling prior to warm up laps. Only then is the engine deemed ready to unleash its 975 HP.
 

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This has happend to me only once, which is once too many on a fuel injected bike. Started the bike, let it idle for several seconds, then touched the throttle in neutral a small bit, and it died.
 
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