New 97 Vfr Owner, Getting Hot While Idling?

Hi guys, I just bought a 97 VFR750 with 21k on the clock two days ago. Ive only rode it about 8 miles total so far so im not sure if it will get hot when riding bc those miles are on two separate occasions. I pulled it in the garage last night and let it idle for about 10-15 minutes in order to see if the cooling fan will come on. Well the temp gauge kept climbing until I shut it off when it hit the last white line before the red/overheat area of the gauge. The cooling fan did come on bc when I turned off the engine it was still running. Unfortunately I dont know when it kicked in bc the bike has a micron pipe on it and its too loud to hear the fan when running. From what ive been able to find out the fan should come on just slightly past the half way point...is that correct? Is it normal for these bikes to get hot at a standstill? Any common problems you guys can share with me? I dont suspect blown head gaskets as it runs great, idles good (although at 1500 rpm instead of 1100-1200 like Haynes recommends), and no white smoke out of the tailpipe. The haynes manual really doesnt help and just recommends to test the thermo switch which I would assume is working since the fan came on. Any help would be appreciated as im a newbie to water-cooled bikes. Hope i didnt buy a lemon and got screwed. Thanks!

Hello Esco,

Welcome to VFRD from across the pond.

My '97 4th gen's fan kicks in only when the needle is well beyond the half way point.

In very hot weather like today (34 celcius) and spirited riding, the fan occasionally comes on at a traffic light.

I have yet to hear of a 4th gen engine going kaput.....

I recommend you check the wiring from the stator to the voltage regulator to the 30A fuse next to the starter relay for any signs of melting discoloration.

Mine never had any issue, but other have had. I pre-emptive fitted a "VFRness" (use the search function).

Other ttat that, check state/age of tires and chain/sprocket.

Oh yeah...

WE NEED A PICTURE!!!! 

Thanks for the reply Dutchy! Ill have to try to listen for the fan more closely to see when it kicks on. Im still concerned about the temp gauge climbing when its just idling. Im going to take it for a ride today and see if it overheats when riding. Maybe its a radiator flow issue or too many bugs in the fins. If anyone else can give me a suggestion id appreciate it. And yes, ill get a pic posted today or tomorrow once I wash it....its supposed to rain today here in western mass. Thanks again!

I think my fan comes on when the needle is very close to the top of the scale, one quick way to test the fan is unplug it put 12volts to it & verify it works then check the thermo switch....

Good Luck

Thanks V-fore. Do your guy's temp gauge ever reach the upper white line? Whether idling or driving?

Never on mine. I think the highest I've seen is about 3/4. Not sure when the fan comes on though. I don't do much city or stop-and-go riding these days.

The radiator fan on my 95 comes on somewhere between the half way and three quarters of the way on the temperature gauge.....
I never saw it go any higher than that. Having it come up all the way to just under the critical zone on the gauge is certainly not normal, as all the years I owned my 95, it generally ran towards the cold side, especially on the highways even at high speeds.
In addition to checking/replacing the thermoswitch, I'd check the whole cooling system for any air cavitation or blockage. And if you haven't changed the coolant in a long time, this will be a good excuse to do so....
BTW, IIRC, 1275 RPM is the idle spec indicated on the service manual for the 4th Gen....

First off thanks for all the replies. Secondly, just an update, I rode the bike for 28 miles today and found the temp gauge reading either right at the midway point or around 1/4 gauge when really cruising at a good speeed. When stopped at lights it would creep up to 3/4 or just a hair under that but would go back down as soon as I started moving. Im thinking too mucn debis in the radiator fins so im going to pull it out next weekend and clean it as well as flush it and the entire cooling system. I am alsogoing to replace the t-stat and rad cap just for peace of mind.

Another thing to check is the fins on the rad itself, especially the back side toward the engine. You can buy a 'fin straitener' from Harbor Freight for a few bucks, well worth the time to increase the efficiency of the radiator itself. The fins get buggered up when folks do plug changes.

once you have done the above and realize the bikes just run hot in start and stop traffic.

unplug the black wire from the fan to the thermo switch..

splice in another black wire to a switch, located at the place of your choosing.

 add a ground wire from the switch :comp13:

 live happy ever after. :wheel:

[image: IMG_20140404_004922_zps2b485cd4.jpg]

check to see how much anti freeze is in the system as well.

I need to correct my earlier post;  the fan comes/came on yesterday when the gauge was "half way"...

This was after a spirited ride, cruising in my home street...

My VFR (1997) can run a little hot but not that much. It'll not go above half-way on the temperature guage and the fan comes on then. Or else some riding at speeds above 40mph will get air moving and ge tthe needle back down.

Is it worth putting on a fan switch? Anything over 20mph would be quicker than the fan would it?