Bike running too cool

[gavvers]

Hi! Currently working on getting my new (to me) '99 VTR up to where I want it. Currently have done manual CCTs, rebuilt the the forks, new tires. Rebuilt the clutch cylinders, chain, rebuilt the carbs, and probably a bunch of other small things I'm forgetting. The bike now running really nice and I'm liking where it's at, other than one thing; it seems to be running very cool.

If I'm stuck in heavy traffic, the coolant will get right up the halfway mark on the gauge and if it goes much above that, the fan kicks right on and cools it off nicely, so it's not an issue in massively worried about since it's definitely not overheating. And I'm fairly sure the gauge and sensor are working correctly since from what I can tell, the fan is kicking in right where it's supposed to.

Since I got the bike, if I'm under normal riding or standard cruise conditions, the needle on the temp gauge only barely gets to the ¼ mark. If it's particularly cold outside, it's even worse and will hover around ⅛ instead. I figured it sounded like a thermostat which was stuck open, but I just replaced the thermostat with a new 75° OEM unit and the temp is still running at the same place on the gauge. The old thermostat also doesn't appear to be stuck open at all.

Should I be worried or concerned? Is there something I'm missing that I can test which might improve the temps? I'd like to get it up to operating temp if at all possible, since it's not like it's an easy bike on fuel!

Thanks in advance!

[sirch345]

Hi! Currently working on getting my new (to me) '99 VTR up to where I want it. Currently have done manual CCTs, rebuilt the the forks, new tires. Rebuilt the clutch cylinders, chain, rebuilt the carbs, and probably a bunch of other small things I'm forgetting. The bike now running really nice and I'm liking where it's at, other than one thing; it seems to be running very cool.

If I'm stuck in heavy traffic, the coolant will get right up the halfway mark on the gauge and if it goes much above that, the fan kicks right on and cools it off nicely, so it's not an issue in massively worried about since it's definitely not overheating. And I'm fairly sure the gauge and sensor are working correctly since from what I can tell, the fan is kicking in right where it's supposed to.

Since I got the bike, if I'm under normal riding or standard cruise conditions, the needle on the temp gauge only barely gets to the ¼ mark. If it's particularly cold outside, it's even worse and will hover around ⅛ instead. I figured it sounded like a thermostat which was stuck open, but I just replaced the thermostat with a new 75° OEM unit and the temp is still running at the same place on the gauge. The old thermostat also doesn't appear to be stuck open at all.

Should I be worried or concerned? Is there something I'm missing that I can test which might improve the temps? I'd like to get it up to operating temp if at all possible, since it's not like it's an easy bike on fuel!

Thanks in advance!

That is more or less exactly when the fan cuts-in on my '99 VTR and has been for the last 24 years. I have always thought that was normal, and nothing has made me think the engine is running over cool,

Chris.

PS. Welcome aboard

[gavvers]

PS. Welcome aboard

Thanks!

I definitely don't think it's over cooling in traffic, but when I'm cruising on the highway it struggles to ever get above the first quarter mark up, which is why I think it's too cool. Feels like it should be closer to the middle even under cruise, with the fan kicking in if it gets above that.

[MacV2]

When you did all the bits to refresh the bike, did you change the coolant ?

If not best to drain, flush & replace with new.

Any brand is fine as long as it's for aluminium engines.

Check the manual for the correct procedure, apart from popping the lower hose off there is a drain bolt on the front head.

[gavvers]

I'll give that a shot.

[sirch345]

PS. Welcome aboard

Thanks!

I definitely don't think it's over cooling in traffic, but when I'm cruising on the highway it struggles to ever get above the first quarter mark up, which is why I think it's too cool. Feels like it should be closer to the middle even under cruise, with the fan kicking in if it gets above that.

I understand what you are getting at, it'll be interesting to see if you come up with anything that changes the way the temperature works atm

Chris.

[SlingVTR]

Mine runs about the same, when running 60/90 mph never gets above a quarter up the gauge but does get hot when sat or not moving.