Skip the Red Unless You got nothing better to do:
So over 35 years i dealt with water cooled electrical equipment, primarily inverters for foundries. Really high energy, capable of vaporizing 1/4 by 4 inch copper buss, and yes even the copper buss was water cooled.
So the words water pressure and water flow are related, however you can have pressure and no or low flow. All crytical devices had elmwood temperature sensors after them on the return side of the water circuit. In my early years I would have repeat failures on some older equipment, primarily what I call now , "toy" inverters 125KW ( 125 HP roughly). I would have a SCR fail or a parallel diode fail, yes on the 125 KW about $1000 and $400. Combine my charge out fee and the down time, this became first a annoyance and then a embarrassment. My parents gave me a name that is not easily forgotten, so when things went South $#@* don't send _______ again, this is getting expensive.
It took me time , what I found was the hose length was engineered that 15 feet of 1/2 inch low conductivity hose and 15 Microsiemen water is equal to 1 million ohms. It took me months to find the why and another 3 months of waiting so I could re-hose the entire cabinet during summer shut down. What happened is the assemblers didn't follow the drawings, especially around the SCR / Parallel diodes, what was to be 15 feet was 3 feet, what was to be 20 feet in some cases was 4 feet. Electrolysis had taken place, ate away at some hose barbs and deposited on others. What should have been 5 gallons per minute was around 3 gallons. So a very hot day, we are running below the sensor for the SCR, they stop the inverter to measure the molten metal temperature. Then start it and run full power to raise maybe 20'C, that sudden full power was enough for the magic smoke to escape, eventually the circuit would trip the sensor, digging into it, I started cutting the hose, the very instant I found the deposit, I knew the why. I have installed roughly 50 miles of 1/2 inch non conductive hose in my lifetime.
Painting a picture here, my #4 T Bob and the original T Bob and last how the Versys was originally controlling engine temperature.
Starting with #4 T Bob, cold start flow is through the engine , through the T Bob housing and back to the water pump through a 3/8 bypass line. That wax cartridge is flooded with the engine glycol coming out of the motor. Next as the engine heats up and we approach 190'F , the stat starts to open, some heated glycol enters the rad , that water is cooled, & depending on air temperature it, comes into the engine , mixing with the bypass line hot water = giving a average of the two temperatures.
If I am at idle , the combined rad and bypass water will affect the engine temperature and in short order stability will occur. If I suddenly accelerate and maintain that energy input, that heat transfer within the engine is almost instantaneous , that heated water travels roughly 8 inches to reach the #4, that increased energy causes that stat to start opening to full open, again depending on air temp it will eventually stabilize . A typical heat exchange is 10'C , that is water going in at 90'C will come out at 80'C at the lower rad hose.
You return to idle, that water pump is moving less water, the energy input is much less, that T stat will probably be fully closed if it is below 10'C outside at idle
So now the original T Bob, we took the thermostat out of the discharge of the motor, installed a bypass line tapped into the upper rad hose and installed a external thermostat that controls water flow into the water pump on cold start up. What we had before was a small bleed hole in the OEM stat, so if you had a newbie that thought he could just start the bike and crank it immediately, well you might have come close to producing steam inside that motor, because you need the set point temperature and flow
to open that stat, look closely at the OEM stat, it is identical to the #4 as to the spring and water pressure assisting the spring.
So we don't do stupid things,we allow the motor to warm up. We have warm , becoming hot water going through the motor , through the bypass line, deflecting off the wax cartridge in the T Bob and returning to the water pump. So let us say, it is at 130'F, you want to get going, you are at 5000 RPM within 5 minutes, you are now producing some very hot water, that stream is going through the bypass line, hitting that wax cartridge and some water is coming through the rad. In this setup, we need to wait until the mixed water travels through the engine to the bypass line and also the effect of the cooled water at the T Bob that has come through the stat. In theory we could have 212 'F water coming through the bypass line and
the water going in at 150'F , depending on flow, we could still have 180'F plus coming through the bypass line . How it could be 100'F or cooler is beyond me. Unless it is like Dave said, the water pump is forcing the T stat open.
What Dave suggests about Tig welding could be very valid, in the location set out by Bill in his original design. I did notice that yesterday. I also looked at the original T stat made for Kawasaki, if you push in the opposite direction, things tend to fall out. It's design was meant to work with the spring not against it.
I think I will skip OEM. If it hadn't been because of the design change on the MK-3 , I would have installed the original T Bob in the same place as everyone else. Because I don't like buying something to replace a perfectly good device, I went at it. The harder I tried, the more frustrated I became. I have been covered in ethylene glycol, it is highly toxic and can be absorbed through the skin, when I say covered, roughly 100 gallons of 50/50 at 90 PSI when a 2 inch hose blows off, because some idiot at the factory forgot to swedge the fitting and never thought of using a proper 2 inch hose barb fitting. I can laugh about it now, it isn't funny then, blew my glasses off my face, I had glycol running out of my boots. Fortunately they had showers and a emergency eyewash station.
So somewhere on this forum I mentioned I drained my 2015 at least 8 times, probably much more than that, I am one determined SOB , when I get a idea, not much stopping me, at one point I came within minutes of taking my sabre saw and doing some surgery on the damn plastic.Well it has been a few years now with the number 4 T Bob, like the new flash it would take about 2 to 3 times the $$$ of what I paid for it to sell it, and I would have another on order, and it would need to be 3 feet of snow on the ground.
Just send a PM to me later Dave
, I can move these posts. For now it seemed like the best temporary location. And if you resolve this, keep the thought of posting some photos along the way. Your action may help 10 other people on this forum. It may also help Bill .