Cooling system problem

[hurricane_r]

hey i just did engine conversion into my bike and engine runs fine,
i just did up cooling system but its a bit weird
the temp gauge is going up down when bike is warm by just moving bike from upright/peg lean

and so its not really giving acurate temp, also how long leave radiator cap off to bleed system

thanks im not know alot about cooling system, anyhelp appreciated

[TLDV8]

Did you bleed the air out of the system ?...The TL has bleed bolts on the waterpump so it is not just a matter of leaving the cap off sometimes.

Where's your Workshop manual.

[hurricane_r]

didnt have one

[TLDV8]

didnt have one

A manual or a bleed screw/bolt

Take a look though the Lotsa manuals online... thread at the top of the page.There might be a CBR250 manual online.

I would think if the gauge is doing what its doing then there is air and lots of it... depending on the temp sensor location,thermostat housing or radiator end tank.

[hurricane_r]

ok i got it, doesnt say anything about how to get air out, only says use pressure tester to check pressure, now i cant get radiator cap off lol

[Tim 39]

sounds to me like the temp gauge is changing when you lean it over, becasue its in the water like it meant to be and when it stands up its not, where's you temp sensor, radiator or head? RS's have an air bleed bolt but just leanin it from side to side and then starting it up gets all the air out, so yours may be the same

[hXc]

You've gone from a CBR250R engine to a CBR250RR right? Did you just change the engine, or the radiator as well? Because if you just changed the engine, then the 250R radiator, probably won't cope with the 250RR engine.

Don't take the above as the truth, as it is only a wild stab in the dark at what might be the problem.

[Sketchy_Racer]

the rads should be the same are they not?

[hXc]

the rads should be the same are they not?

I'm not too sure, that's why I said don't take it as truth.

[Sketchy_Racer]

Even if they aren't. The engines are exactly the same..... So the MC-19 rad should be able to cope no problem.

[F5 Dave]

Yeah but what about that extra 'R'?

I mean, I wouldn't take the risk.

[Sketchy_Racer]

The extra 'R' fell off in the conversion!

[imdying]

They're the same motor making the same power and thus creating the same amount of heat to dissipate. No problem using the single R radiator is what I'd put my money on.

[F5 Dave]

The sarcasm is so thick you could spread it with a knife, however your grammar is worthy so I won't rip any piss.

The temp gauge is a simple ammeter measuring a temperature variable resistor, there is a constant voltage & the thermistor (temp resistor) is the small sensor in the front of the radiator (the big one is the fan switch).

These thermistors take a little time to change temperature so the leaning the bike over change; is likely the gauge has very poor damping, I wouldn't worry about it as long as there is water in the system it should be fine. Most roadbikes are self bleeding, never seen a bleed screw on a multi before.

You may just want to check the connection plug to the thermistor isn't dicky. Perhaps if this was bad it could be moving.