Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

CBR250RR wont start!

Discussion in 'Technical and Troubleshooting Torque' started by ronin2010, May 13, 2007.

  1. ok so ive been looking around the forum but havent got any answers for my situation.

    Ive got a CBR250RR, when attempting to start it, the starter motor just keeps going. occasionally it kick over for a few second when the choke is on but dies straight after or when you give it any revs. now its possible that the idle has been played with aswell...

    it was running great not long ago, starting straight away. im not sure what happened.

    any help is much appreciated, i really just want to get it running so i can take it for a service! too bad mechanics dont do house calls lol

  2. maybe the colder weather? now i set the choke gradually while starting and seems to fix the issue.
  3. Try getting it started with the choke on but turn it off gradually (but still fairly quickly). You're engine is pbly finding it hard to start because its cold, then after a while its being drowned by fuel.

    I don't know about where you are, but we have some dial-a-mechanics here. They do house calls, if not rent a bike trailer for a day.
  4. Hey Nath, seems like I have the same problem like you with my cibby too! One minute its working without me even trying, next it just wont even start..... :shock:
  5. Try pumping the throttle once or twice before you push the starter button... can't hurt, can it?
  6. Motorcycle carbs don't have an accelerator pump or automatic choke to set, so pumping the accelerator achieves nothing.
    Full choke till it starts, then some throttle once it catches, and slowly reduce choke.
    Cold engines need a rich mixture, and teh choke provides it.

    Regards, Andrew.
  7. Full choke - no throttle (cant stress this enough).

    Once it starts to fireup (you'll hear it), apply tiny amount of throttle to bring the engine to life. This may take a few goes to get it. keep your throttle open and slowly reduce choke. Don't let the revs drop too low or it will might die.

    Once the engine is warmed up everything should be sweet.
  8. ok guys ill have another look at it tomorrow night...

    as it is, it sometimes starts (with the choke full on) but dies very quickly and even if i use the throttle even the slightest. worse case i think i can get a bike trailer and take it to my local honda dealer. but really id like to have it running and be able to ride it there and get it serviced!

    btw i havent had the bike running properly for over 3 weeks now

  9. start ya bugger
    battery charge or a good loong clutch start
  10. Maybe your flooding it? What happens if you use no choke and try and start it? Maybe the battery has gone flat and doesn't have the power to start it?
  11. May be fuel blockage, just dribeling enough fuel to catch and idle.
  12. hey ive tried it again.... still didnt start, i even tried getting it rolling and clutching it. but still didnt start the slightest, it even backfired!!

    i think im gonna need to get someone to look at it... :(
  13. like the guy said up there ^^^

    u've flooded your bike. after so many attempts at firing up, your cylinders will flood and foul your plugs.

    u'll have to clean them, or at least replace it. Try doing it yourself (it's a biatch) because u'll learn something new and save a bit of money in doing so.

    but before you do that, make sure you have fuel in your tank, and that your kill switch is not on the OFF position.
  14. I agree that it's plugs, but If you're going to pull the plugs, you might as well replace them... Last time I bought plugs, they were $6 each.
  15. The only other way to clear a flooded motor is to hold the throttle wide open and crank it over. This will allow a lot of air in and only a small amount of fuel. do not use the choke at this point as it will make it worse. The choke is designed to minimse the air supply so the engine will draw more fuel on start up, so leave it off. Bear in mind that if it does start, it will rev really high so you have to be quick and careful not to do any damage as the engine will be cold. If your not game take out the spark plugs and replace them. This is the best possible senario.

    P.S. In case you are wondering if I know what I am talking about I am a Mechanic/ Auto Electrician
  16. Hey Disco did when you said to open the throttle while cranking over did you mean to also have the fuel switch turned to off?
  17. No leave the fuel in the on postion. The bike will never start with it in the off postion, or it might, but will stall shortly afterwards leaving you more confused. Getting a motor started that is flooded takes a bit of practise but dont be too afraid to keep reving the motor 4 - 6 thousand RPM after it is started as it will need to remove a lot of crap that is in the combustion chamber. It may also miss and splutter a bit but with persistence will come good.
  18. ok i gave it a go this morning and got nothing.....

    i also gave it a try while the bike was rolling and let the clutch out at the same time, i got some spluttering but nothing more.

  19. I'm no mechanic but have you tried a fully charged battery, since you changed the plugs etc? I couldn't even roll start my bike when it had a flat battery.. It just coughed and spluttered..
  20. DODGY FUEL!!!! Drain fuel and get some fresh stuff.
    Check the spark plugs, carb/ fuel line blockage.