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Discussion Starter #1
So I've had my CBR300R from new about 6 months and just hit 4500km and so far its been faultless (one random cutout the exception).

Anyway, my bike is garaged every night and the other morning I come to fire it up for work after the weekend and it refuses to start. Goes through the fuel injection part (i think thats what it is, where the taco spins up) but when I try and fire it up, the bike cranks over but doesn't start. I thought fuel, but I'd only filled it up 2 days prior. It was cold that night (6c in the garage) but its been colder and not had issues so dont think it was that. I kept cranking it and giving more throttle but nothing after 15-20 secs. I give up, flustered and thinking of taking the bus, but give it another go and after another 20secs when I thinkt he battery is going to die, it starts to cough then fires up and ran fine.

4 days later leaving work in the afternoon, it struggled to start for 5secs then fired OK and then today it did the same. Not cold at this time, 18c and a different tank of gas.

Any suggestions what might cause it?
 

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Hey Puk, your sure clocking up some K's on that 300R.
Is it running normally once you get it started? Is it only on a cold start that it sometimes does this?
I'm wondering if the ECU is not metering the fuel/air mixture correctly on a cold start.
At least you have a 24 month warranty to fall back on. Could be a job for your dealer to look at.
 

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Hey Puk, your sure clocking up some K's on that 300R.
Is it running normally once you get it started? Is it only on a cold start that it sometimes does this?
I'm wondering if the ECU is not metering the fuel/air mixture correctly on a cold start.
At least you have a 24 month warranty to fall back on. Could be a job for your dealer to look at.
Ha sure am! Daily commuter for me replacing the bus. North Shore to CBD and back so 40km a day total.

yeah once its fired it runs fine. I think you nailed it with the ECU, that never crossed my mind actually as I was just thinking cold and fuel. When it does fire after the issues it sounded "rough" for a few seconds so yeah, could the ECU playing up. Will take it back to the dealer I think just to be sure.
 

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Someone posted a while ago about their 300 losing power and turning into a choking dog while they were riding it, and when they removed the seat so inspect, they found a small piece of an aftermarket part they had installed that had come loose and got sucked into the air filter. If there is leaves or other debris in there it could be confusing the ECU due to a lack of airflow.
 

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I suppose I've had some similar instances happen about a month ago... But it started up later, and the issue hasn't repeated and has started normally ever since (knock on wood).
 

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Hey guys, thought I would resurrect this one than starting another. Seems like I have been having something similar as of late. It's a '15 with only around 3600 miles, but the bike just cranks and cranks for about 10-15 seconds before firing. Riding it seems okay, not sluggish, no misfiring, nothing out of the usual. It is only starting.

I recently put fresh gas in, changed the oil, checked air filter, everything is new and in spec. Possibly an electrical problem? Though I'm the world's worst electrician. The battery, however, is still the original but still seems to hold charge just fine. I tried checking the spark plug but unfortunately it cannot be taken out without removing the fuel tank, there's just simply not enough room. Looking if anyone has any ideas before venturing down this path.
 

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Hey guys, thought I would resurrect this one than starting another. Seems like I have been having something similar as of late. It's a '15 with only around 3600 miles, but the bike just cranks and cranks for about 10-15 seconds before firing. Riding it seems okay, not sluggish, no misfiring, nothing out of the usual. It is only starting.

I recently put fresh gas in, changed the oil, checked air filter, everything is new and in spec. Possibly an electrical problem? Though I'm the world's worst electrician. The battery, however, is still the original but still seems to hold charge just fine. I tried checking the spark plug but unfortunately it cannot be taken out without removing the fuel tank, there's just simply not enough room. Looking if anyone has any ideas before venturing down this path.
Unfortunately you really do need to check the plug. Pain I know.
Another cause of poor starting can be valve adjustment out, but you would like to think that at 3600miles it wouldn't be this either.
What color is your pipe tip?
 

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aside from plug or valves etc, are you using throttle starting?
recommended routine includes no, throttle..
my 3 [one cbr250r] all started first touch
after, discovering and using the no throttle method..
including cold early morning starts [not freezing]..


a general starting hint ive used after leaving the key in
overnight was to clutch start her.. i have a nice sloping road
which makes it easier, but also clutch started her on almost
flat at the other end of my usual runs in those sequences..
as long as you can get a good runup [or someone to push]
i found second or even third on downslopes works well..


also a good idea to use the same petrol outlet if possible
esp one with good thru-put of cars, meaning regular
fills with fresh fuel and less opportunity to settle
in tanks [esp with ethanol blend fuels]..
 

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Unfortunately you really do need to check the plug. Pain I know.
Another cause of poor starting can be valve adjustment out, but you would like to think that at 3600miles it wouldn't be this either.
What color is your pipe tip?
I knew it was gonna have to be done, considering the checks are in most of the other boxes haha. As for the pipe tip color I'll have to get back to you. It's been chilling in the back of the garage for the past few days but I'll be working on it later today.

aside from plug or valves etc, are you using throttle starting?
recommended routine includes no, throttle..
my 3 [one cbr250r] all started first touch
after, discovering and using the no throttle method..
including cold early morning starts [not freezing]..


a general starting hint ive used after leaving the key in
overnight was to clutch start her.. i have a nice sloping road
which makes it easier, but also clutch started her on almost
flat at the other end of my usual runs in those sequences..
as long as you can get a good runup [or someone to push]
i found second or even third on downslopes works well..


also a good idea to use the same petrol outlet if possible
esp one with good thru-put of cars, meaning regular
fills with fresh fuel and less opportunity to settle
in tanks [esp with ethanol blend fuels]..
I've never done throttle starting as it always fires on either the first or second crank of the starter. I do always try to use the same fuel station, which is usually pretty busy, but maybe I'm choosing the wrong one! Considering draining the tank and starting over with brand new fresh gas from somewhere else.

As always, thank you gentlemen!
 

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We have a 17 CB300F with about 650 miles on it. If it sits for about 2-3 days, it will start, but it isnt happy about it. It's a rough start, and a rough idle for about 20 secs, sometimes it even stalls. But as it warms up, it smooths out, and everything is good. Warm/hot starts are fine, its just cold starts. It's been that way since day 1. We have a 14 CRF250L, and it could sit 2-4 weeks, but it starts great every time and the first time. I just assumed it was the nature of the beast since it was day 1. Our 06 goldwing is finicky, but its an 06, it doesnt get used often, so it's understandable. But the CRF, grom, and FJ09 never have cold starting issues.
 

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@kiwi rider, I checked the exhaust tip yesterday and it has no discoloration. I'm thinking dying battery, simplest solution is usually the right one
Agreed. I work in a mechanical maintenance workshop and time and time again issues come back to the battery despite perhaps initially not appearing to be the cause of the problem.
 

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My 2015 with about 3k miles generally cranks for about 5-10 seconds when cold. When warm it fires right up. I always run ethanol free with stabil. I never worry about mine. Cheers!
 
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