NC30 getting far too hot

[oliherst]

Some of you may recall my thread on the old boards, the one when I cracked the sump

Well, since getting all that fixed and putting some miles on the bike, I noticed it was getting very very hot. Last summer when I got the bike I'm pretty sure the temp needle would sit around the middle of the guage, and when turning off the bike the fan would only come on if I had ridden for more than maybe an hour in the full summer heat.

Now, I have ridden the bike on the really nice days this year and there is definately something wrong. The needle is way up the high end of the guage and after almost every ride the fan kicks in.

I asked some bike friends who suggested maybe a fluid leak or a dodgy thermostat. Eitherway, as the bike is my first and I'm keen to learn, and as I haven't done anything about the cooling since I had it, I have jumped right in at the deep end

I drained the fluid (well most of it, still have one bolt I haven't managed to get out) and have now removed the rads...infact I'll get some pictures up after dinner.

And finally to the point - What am I looking for? How do I know if the rads/hoses are ok? Do I need to get the water pump out and check that? etc etc. Also, I noticed with the rads off, its very easy to get to the plugs and exhausts (both of which I have done in the last 6 months anyway) but is there anything else I should do whilst I have access with them off?

Thanks all

[wullvfr]

you can do the usual checks....leaks,check the level!!!!the fan works and so does the thermo switch so i would double check the thermostat is working..is the engine definately overheating?maybe double check the temperature switch which is on the thermostat,it could be playing up!!!probably not though as the thermo switch works by the temp so i doubt the both of them being dodgy.the thermostat is maybe not opening up so the coolant is not flowing through the rads!!!!! :D :D

[oliherst]

Right, here are the pictures I have just taken (NOTE - Lots of pics!!):
Top rad front:

Top rad back and close up:


Bottom rad:



Water pump:


The bolt that is currently stuck:

[Sligeach]

due the size of the radiator and the compactness of the engine MR Honda designed it to very fine spreificatitons. i have found that i have soaked my rad for a day twice all ready this year.
due to it low low it gets full of crap and really does effect the cooling capacity of the rad.
by the looks of things you have it off already so stick it mucky side down in a tray of water, then give it a very gentle rub and genlte stream of water to shift thee muck.
you should be able to see through to sunlight on the otherside of most of the rad

[TonyB]

+1 on soaking the lower rad and gentle cleaning of the fins.
It will make a huge difference if done carefully and not damaging the fins.

[fastdruid]

You can straighten out the fins on the upper radiator in those flatened area. I use a very small flat bladed screw driver to (very carefully) do it. Takes an age but if you've got large flattened patches is worth while IMO.

Basically you should be able to see though all of it and if you cant then it should either be cleaned or have the fins straightened.

Druid

[oliherst]

Thanks for your input guys. I'm currently sitting in the kitchen wathcing my thermostat boil. Just got a thermometer from Robert Dyas to test it. I'll let you know the results in a few mins :)

I'll be giving the rads a clean and tidy up shortly as well. I get some pictures once thats done :D

[Sir Choice]

Cheers guys, i Think when ive got some time ill try remove the radiator, it could probly do with flushing and de-bending as i cant see a thing through it lol.

im starting to wish id gone for a cbr 600, this bike just needs alot of tlc it seems to get it working nice

[katana]

What did you guys soak the radiators in to get the gunk out of the fins?

[fastdruid]

I just use warm water and some washing up liquid.

Druid