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CBR getting hot temp

Discussion in 'Bling and Appearance' started by TristanO, Nov 16, 2006.

  1. I've got a CBR250rr. When riding, if i have to stop and start alot the bike gets quite hot (approaching max heat) . Is this normal for these bikes in stop start conditions? I'm also told these bikes should always be ridden at very high revs to avoid build up, Is this true

  2. fan working? coolant?

    When my temp approaching the 1st quarter of the guage.. I could hear the fan goes off...
  3. Yep, hot-foot it (groan) to your mechanic and get the thermo fan looked at and /or fixed. It's not cutting in and you're cooking your tiny little pistons.....
  4. Make sure that the radiator is clean. Undo the drain plug and flush it out several times with a garden hose, you might be surprised at what comes out. If the cooling performance is still borderline, unbend/unblock all the radiator fins by inserting a small file or similar.

    9 times out of 10 this will solve your oveheating problems, at least it has for me.

    The fan usually cuts in at just over 100C, if your radiator is gunked up it will do little to help the water cool down.

    If the fan's working, you can hook up an override switch, which may be useful in traffic before the problems start.

    Most (older) bikes will get noticeable warmer in traffic conditions, the best way to cool the bike though is to get up to speed.
  5. Cammo, Are you sure it is 100 degree Celsius? It would be boiling if that's the case... I reckon it's something less than that.
  6. Cooling systems are pressurised, this raises teh boiling point of the coolant, and also allows a more efficient cooling system.
    First I'd have the temp gauge verified and as said above, the thermo fan switch.
    Shame, I did a bit of a write up a while ago here on cooling system diagnostics/fault finding...is the search still non functional?
    My bike wil run about 1/3rd off cool when travelling, but will go to 3/4 hot in heavy traffic. It's normal on some bikes for this to happen, it just means teh bike has a nice large radiator, and too small a thermo fan! :roll:
    Regards, Andrew.
  7. i think thats common on the 250cbr. my bro has the same problem. the fan will kick in when near hot but when he rides it cools back down. it doesnt ever touch the hot red line. maybe u can do something to make the fan kick in earlier.
  8. Thanks for the help. I will have a play around and see whats going on. To be honest I have never heard my thermo fan going, maybe it's broken. Wheich would explain it getting hot at a stand still
  9. On my little bike (same) I had the same concern. I took it to the mechanic and he checked the fan and said it was all good, despite me never hearing it. As he said, put your hand on the gap of the fairing on your left and you'll feel the heat being blasted out. Mine gets close to red line, but not on it. They told me to keep an eye on it, but these bikes can get hot. Mine will be serviced on Wed, so if they find anything wrong to do with heat, I'll let you know.