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cbr250rr running hot.faulty gage or possibly water pump ?

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by deanfoldi, Dec 7, 2007.

  1. hey there guys just a question.....im a new rider and i have a cbr250rr and it seems to run pretty hot at the coolest it is around half way..... now if i stiop at traffic lights the temp gauge can go any where from 1 mm off the red and some times even into the red.
    but if i give any kind of throttle it seems to instantly bring the temp back to around half way as long as i keep the throttle on.
    i have checked my fluids there all ok. but when i start the bike and look in the radiator there is no movement does not look like the coolent is flowing. i had one machenic say it may be the water pump then another say it might be electrical.... has any one else had this problem ?
    thanks for ur time guys .

  2. from a mechanical point of veiw i would say thermstat may not be opening properly if it has one or check if the wire is not earthing out or faulty sender
  3. LOL this gives me a good excuse to buy a infra-red tempature sensor :grin:
  4. thanks

    im not sure bout either im only new to the bike scene ill order a manuel online some where so i can try and check those things . thanks for ur help :)
  5. thermo fan, buddy, thermo fan.
    it is not coming on, busted switch/dodgy connection/buggered fan.
    you wont really see "flow" in the radiator.
    edit- the thermofan comes on when the temperature rises due to insufficient airflow through the radiator. when you are pulled up and its rising, you should hear it kick in (sounds like a, well, fan humming) see if you hear this, if not, there's your problem.
    take it to your nearest bike doctor and tell him to fix it.
    also, it is common for older bikes to have a switch hard-wired so you can decide when to turn it on, eg. any time you know you are going to be in heavy traffic. this will avoid it getting to critical temperatures.
  6. ok cool. well i checked that the other day it seems to come on but u cant hear anything could that mean its not workin as well as it should be ?
  7. I think there is a few faults there. With my bike it wou;d run at about 1/3 the scale in light traffic/cruising. If I'm starting to go in a few lights and some traffic it would be about 2/3 and the highest ever only 3/4 of the gauge since the fan would switch on..

    I think that first it's the fan. It doesnt seem to be working properly and also check the thermostat. I think it's not letting enough water through.

    As for the flow of coolant in the radiator. you can see the coolant level in the radiator drop a few mm when you rev the engine.

    Hoped I helped....