V-Max overheating?

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FWIW - I run a Borg-Warner fan switch - p/n TFS545
A Stant thermostat p/n 13758 180 degree
Hyperlube & water mix - no antifreeze
My bike now just barely runs over half-way on the temp gauge when the fan kicks in. I don't need antifreeze because I'm in central FL, but I don't recommend that for anybody north of here. The "snake-oils" like Hyperlube & Waterwetter & such work by breaking down the surface tension of water allowing it to flow into the microscopic nooks & crannys of the inside of the cooling jackets - it basically increases the surface area. Racers often don't run coolant because it's banned in many forms of racing - a wreck or blown hose would allow slippery coolant all over the place - hot water on the other hand will evaporate quite rapidly.
Just my 2 cents...
 
Never use water instead of cooland liquid. Water will make all the cooland system rust. I've been there i learned my lesson. Trust me. If you use water after one year when you want to change it you want see water but a brown shit which name is rust
 
I noticed that my temps go up in hot days and stop and go traffic too. Temp getting near the red.
I was worried about, so I started it at home and let it run till it heated up to the point the fan just came on and hit the rad and rad hoses with a infared temp gun and was surprised to find it was only running at 185 degrees. Not that worried anymore. See this link as I have one from being a caterer and always needed to check temps. Just point laser and get a reading.
http://www.princessauto.com/tools/auto-repair/diagnostic-tools/8223570-laser-thermometer

Grant
 
Man the thoughts on tthe water better/anti freeze better subject is all over the board.
I have always heard that Straight water cools the engine better than antifreeze. that antifreez is to keep from freezing and to lube in internals. don't know for sure tho.
I also am wondering about the thermostat question and about it opening at a certain temp?
I thought that the thermostat is for activating the fan at said temp? not opening up like in a car.
 
Water is the best conductor of heat. The water wetter improves the surface tension of the water to let it conduct the heat a little more efficiently. A/F as you noted helps prevent freezing as well as lubrication of the parts but it also helps raise boiling temp of the water. The radiator cap actually helps to raise the boiling temp of water by allowing for the pressure to increase. As water is pressurized the boiling temp is raised. That's how you can get water to go well over 212 degrees before it boils and steams out.

A hotter engine burns more efficiently which is why most manufacturers run the cars with 195-210 degree t-stats. A cooler engine makes more power (at least cooler combustion chamber anyway). But, the oil is a bit harder to push around so you have to be careful to not run it hard when it's cold. Some heat in the combustion chamber is actually good and easily seen on the dyno. It usually takes anywhere from 3-10 consective pulls to get the max HP reading. It's not unusual for the HP to climb 4-10hp by the time it quits making the power increase (note for you guys getting dyno runs done - have them keep pulling runs until the power has it's first drop).

Our T-Stat does the same thing as a car. It regulates the flow of water/coolant. Without anything the fluid flows too fast to both heat up and cool down effectively. So, it takes a very long time to get warmed up but then keeps going and won't cool down either and you end up overheating. I am not 100% sure where our stats open but want to say it's in the 210-220 degree range. I'm not sure if there is another lower temp stat that is available.

We usually run a fan override manual switch to turn the fan on earlier to help the radiator control the temp at low speeds. The aftermarket sending units available do this at an earlier temp but typically end up running all the time once warmed up instead of cycling on and off. Not sure how long it would take to wear out the fan motor but most of the time the fan doesn't need to run while you are cruising down the road (unless it's a really hot day).

We have multiple sending units on the Vmax. One (the two wire plug) runs the fan and is what most people swap out or tie into to make the fan work sooner (or come on manually). The other is the very small unit and is what drives the gauge. The t-stat is a mechanical device and if you want to see how it works then get a pot out and boil some water with it in there and watch it work. There is nothing to let you know when and if that stat is working. You will notice that the t-stat does not 100% seal off the flow when the engine is cold. This was done so fluid pressure from the pump (which does run all the time) can still move around and not cause too much back pressure.

We have got an experimental (modified) impeller we are trying out and waiting for good feedback from the 2 guys with them. I think idle temp may run higher with it but temp once underway should be lower. One of the real limiting factors is the radiator size. It is designed to be ideal for the stock engines HP (more HP generates more heat). So bigger bore engines put a little more stress on the system.

Of course the tune of the bike can also effect it. Too rich or lean can cause excessive heat (typically too lean is hotter running but does make more HP).

Some have noted that the OEM gauge is not necessarily very accurate.

Sean
 
I rode my Max in Yuma Az with temps in the high 90's and noticed that the bike was always close to the red zone. I ordered the fan switch replacement and water wetter from vmax outlaw. After I installed both, and a complete coolant flush, I did notice that the bike seemed to run a little cooler.
 
We usually run a fan override manual switch to turn the fan on earlier to help the radiator control the temp at low speeds. The aftermarket sending units available do this at an earlier temp but typically end up running all the time once warmed up instead of cycling on and off. Not sure how long it would take to wear out the fan motor but most of the time the fan doesn't need to run while you are cruising down the road (unless it's a really hot day).

I can attest to this problem - my max is fitted with a lower temp switch that turns the fan on earlier. As a result, the fan is *always* on once the bike is warmed up (I am in Florida). I fitted a manual fan switch, not to turn the fan on but to actually turn it off - as Sean said when cruising (even on a hot day) there is no need for it as the system copes admirably and keeps the gauge half-way up.
I also noted better mpg with the fan off at highway speeds - I went from 95 to 105 miles from full tank to reserve light after turning the fan off.

Now I wish I could wire up my override switch to the turn signal cancel circuitry, so it automatically comes back on when I'm stopped...
 
Hey Sean
We still havent had enough "hot" days for me to get a good feel for the modified impeller.

For a stock bike I think it will be fine, like we noted, idling temps will be higher due to the lower RPMs and the less number of impeller vanes.
Cruising around town slowly it performs a bit better but when stopped at a red light it creeps really fast toward the red line, the second red line.
Also going up hill it performs better than the stock impeller due to more flow.
For modified bikes like mine that have run hot from the beginning I think it might take a combo of Water Wetter, Manual Fan switch and your impeller to get the overheating under control.
 
I want to use a half vane modification next. Wondering about even getting with Jedi and having a custom impeller made that is "taller" and the using one of our modified covers to clear it.

Sean
 
I want to use a half vane modification next. Wondering about even getting with Jedi and having a custom impeller made that is "taller" and the using one of our modified covers to clear it.

Sean

Sean
Are you talking about half the height or half the length.
If it is the height it wont work. The vanes have to be tall enough or they wont grab any water. Same with the length. It wont throw any water towards the volute.

Try 6 vanes instead of 4. Just machine out 2 opposing vanes. Should be a good mix of pressure and flow and will still be balanced.
 
Your idea of a taller one will work as well. All 8 vanes, that will give us the pressure and taller vanes will move more volume. Not sure how it will affect HP. Moving more water will put more of a parasistic load but it shouldnt be too much.
 
Do you have some more details about this fan blades. Do they actually help keep the system cooler?

I put one of these on in less than 30 mins-
It took 1 week to get here from china.
It holds more fluids and has more cooling fins than the stock one.
Mine has never run above 1/2 way since and i have a custom built radiator cover on that lets little air in.
Another member on this site said he could not thank me enough.

http://www.ebay.com/itm/Aluminum-Ra...007-/121637309130?hash=item1c52260aca&vxp=mtr
 
Thanks for link. I'm a bit worried to spend money on the wrong thing though. I am still trying to figure out the overheating source. Already changed thermostat, radiator cap, fan switch, but the bike still gets close to red on traffic. There is a bit of oil in the coolant.

Sent from my HTC6525LVW using Tapatalk
 

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