cooling system

[Sharky]

Had this info sent to me....looking for second opinions......

"Yeah, the radiator....as you prolly know, the Max runs pretty hot on a hot day, the rad capacity is right at the limit in the heat.Don’t know if you know this but one of the contributors to the ‘hot’ temps is the fact that the by-pass piping (from the RHS coolant manifold to the thermostat) does not go through the radiator. Even when the thermostat is fully opened the coolant still still flows from the heads to the manifold to the thermo to the pump, by-passing the rad completely.. What Yam should have done is to cool the bypass. The by pass flows around 20% of the pump’s circulation thru the 12mm diam hose, so 20% is uncooled coolant circulating back into the system. If I was getting a rad made I would have this factored into the design or look at increasing the rad capacity.*Todays rad materials have improved a bit from the original Vmax, 25 years ago so that might help.. FWIW. My present scoot is a XVZ 13TF Venture which still uses the same by-pass system but the rad capacity is about double the Vmaxes."

 

[maleko89]

I agree that hot coolant is allowed to bypass the radiator at operating temps but not sure how much of impact that is...but I'm sure there is some impact. I don't agree that the radiator is at the heart limit....guys with 1500 engines have used stock cooling with zero ill affects. The only reason I went to a cooler fan switch was because 200+ degrees doesn't feel too good at stop lights.

 

[naughtyG]

When I had a cooler fan switch in FL my fan ended up running too often (for example when cruising on the freeway at 80+ mph) and somehow that took 10 miles off my tank range. I ended up add a manual 'off' switch and all was well.

Here in Perth, I was riding - quite slow as I was pulling a trailer - all day today in very hot conditions (close to 40C / 111F) and the 2000 vmax with stock cooling and thermostat did run quite hot, but kept happily under red all arvo and back to middle of temp gauge whenever I got to go at a steady 60km/h.

Don't think there's anything wrong with the Max cooling - if one runs too hot it most prolly needs a good flush and fresh water/coolant. IMHO of course.

 

[MaxMidnight]

Tend to agree that in a properly functioning system there ain't much wrong.
The biggest impact will be in poorly maintained systems where lack of corrosion inhibitor over the years has allowed the radiator core to fur up and reduce coolant flow.