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Just got off the phone with a guy from "Two2cool". Here's some food for thought. The oil/coolant heat exchanger transfers heat from one to the other. Oil temps generally run hotter than coolant. Therefore the oil is heating the coolant, particularly in traffic and at rest. Could this be part of the problem? If I could find the space I would totally remove that exchanger and install a dedicated oil cooler. We also discussed the water pump situation. Speeding up the flow of coolant is not necessarily the best thing to do as there is a certain optimum "dwell" time of the coolant in the rad to extract the most heat vs not enough flow to cool the engine. Airflow vs coolant flow. Where's the optimum point?

I am going to add some of this two2cool to my oil and see what shakes out. It works or it doesn't. Either way no harm done. So chew on it boys.
 

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I always thought the "dwell time" was an important factor and the reason you should not completely remove the thermostat. I am also confused about the heat exchanger. Why wouldn't mv just make the bottom radiator an oil cooler if oil temps were a problem?
 

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lee said:
Just got off the phone with a guy from "Two2cool". Here's some food for thought. The oil/coolant heat exchanger transfers heat from one to the other. Oil temps generally run hotter than coolant. Therefore the oil is heating the coolant, particularly in traffic and at rest. Could this be part of the problem? If I could find the space I would totally remove that exchanger and install a dedicated oil cooler. We also discussed the water pump situation. Speeding up the flow of coolant is not necessarily the best thing to do as there is a certain optimum "dwell" time of the coolant in the rad to extract the most heat vs not enough flow to cool the engine. Airflow vs coolant flow. Where's the optimum point?

I am going to add some of this two2cool to my oil and see what shakes out. It works or it doesn't. Either way no harm done. So chew on it boys.
I don't think it is part of the "problem" since generally you want to maintain an optimum oil temperature. Oil viscocity is dependant on temperature so ideally you want to keep the temperature between a certain range. The oil/coolant heat exchanger is going to keep the viscosity right when its either too hot or too cold. I would not want to try to bypass this system without really studying the temperature ranges etc. since the journal bearings are designed with a specific viscocity in mind.
One thing I have considered (really more as a thought exercise since the temperatures don't really bother me that much) is the switch from the mechanical water pump to an electric pump. The benefit there is that you could remove the thermostat completely as well as operate the water pump at its optimal speed AND in steady state. The big benefit to operating the pump in steady state is that you are not continually accelerating and decelerating the mass of water; instead you are simply putting in enough energy to overcome the frictional losses. You can control the temperature of the system by turning the pump on and off. The only real question is can you purchase a pump that is compact enough to use and runs on 12 V.
 

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RobP said:
I don't think it is part of the "problem" since generally you want to maintain an optimum oil temperature. Oil viscocity is dependant on temperature so ideally you want to keep the temperature between a certain range. The oil/coolant heat exchanger is going to keep the viscosity right when its either too hot or too cold. I would not want to try to bypass this system without really studying the temperature ranges etc. since the journal bearings are designed with a specific viscocity in mind.
One thing I have considered (really more as a thought exercise since the temperatures don't really bother me that much) is the switch from the mechanical water pump to an electric pump. The benefit there is that you could remove the thermostat completely as well as operate the water pump at its optimal speed AND in steady state. The big benefit to operating the pump in steady state is that you are not continually accelerating and decelerating the mass of water; instead you are simply putting in enough energy to overcome the frictional losses. You can control the temperature of the system by turning the pump on and off. The only real question is can you purchase a pump that is compact enough to use and runs on 12 V.
I had the same thought a while back. Like you I haven't really had a problem with overheatting due to living in UK. Demon tweeks sell a couple of compact pumps that run on 12V systems.
http://www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=MCYCLE&pcode=DCP9001
Not sure if they would fit in place or not but maybe worth a look.
 

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Discussion Starter #6
Right-o about the oil temp/viscosity. I didn't mean to infer that something should be done about oil temp, which it is my understanding should be 220F +or- so as to maintain the vis and not "cook" things out of it. I was just rambling about the oil adding heat to the coolant and it's contribution to high coolant temps.
 

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I've tossed this electric water pump idea around for a while now, and whilst Craig Davies make a little pump that would fit the MV, I do wonder as to the fact that the quicker the motor turns the more heat it would make especially if under load, and hence the more water/greater flow it would require to lose this heat :)
 

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mikef4uk said:
I've tossed this electric water pump idea around for a while now, and whilst Craig Davies make a little pump that would fit the MV, I do wonder as to the fact that the quicker the motor turns the more heat it would make especially if under load, and hence the more water/greater flow it would require to lose this heat :)
I think if anything the heat from the electric motor would be trivial. If you remove the mechanical components of the water pump you dont have the parasitic drag of the impeller, gears seals and what not. You still need a certain amount of power from the engine to run it (you don't get something for nothing) so if it takes 3 HP to run the engine driven waterpump then electrical system needs to draw 3HP to run the electric pump. I think the losses and efficiencies would be a wash between both systems. But I think what really helps is the steady state operation where the work input only needs to be high enough to overcome the frictional losses. Couple that with the impeller operating at its most efficient range and I think you will have the most efficient system. As I said though, it is a bit of a mental exercise for me since I am not really bothered too much by the overheating.
 

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RobP said:
I think if anything the heat from the electric motor would be trivial. If you remove the mechanical components of the water pump you dont have the parasitic drag of the impeller, gears seals and what not. You still need a certain amount of power from the engine to run it (you don't get something for nothing) so if it takes 3 HP to run the engine driven waterpump then electrical system needs to draw 3HP to run the electric pump. I think the losses and efficiencies would be a wash between both systems. But I think what really helps is the steady state operation where the work input only needs to be high enough to overcome the frictional losses. Couple that with the impeller operating at its most efficient range and I think you will have the most efficient system. As I said though, it is a bit of a mental exercise for me since I am not really bothered too much by the overheating.
I think Mike was meaning that it makes sense that when the engine is running at higher rpm, it generates more heat, thereby requiring more coolant flow from the faster spinning of the water pump, rather than the constant speed of an electric, regardless of engine rpm?
 

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fazer6 said:
I think Mike was meaning that it makes sense that when the engine is running at higher rpm, it generates more heat, thereby requiring more coolant flow from the faster spinning of the water pump, rather than the constant speed of an electric, regardless of engine rpm?
If you size the pump appropriately it will meet the needs of the engine at maximum RPM giving you the colant flow you need at constant speed. If the engine speed drops you don't necessarily need maximum coolant flow but it won't hurt. It will just drop the temperature faster. If you use a thermistor switch you turn it off if the temp drops too low and turn it back on after the temperature rises again. Not a problem.
 

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MV-999R said:
That an interesting info, no doubt.

But what exactly is that two2cool ?
:ahhh: :ahhh: :ahhh:

http://mvagusta.net/forum/showthread.php?t=13266


With regards to the coolant flow I suggested that (in the impellar fix thread http://mvagusta.net/forum/showthread.php?t=12565&page=14&pp=10 ) that the 636 impellar may be slowing the coolant flow rather than speeding it up (which now another highly experienced race mechanic has said he used to do for race bikes...either way it appears that the coolant flow via the OEM impellar may not optimal...with the modded impellars soon to be on thier way we should have an answer.

I'm going to hold off putting the 2 cool in my bike as engine temps were not an issue for me until recently and it appears that they are a result of a thermostat on the way out so I'll change that and see what happens with the new impellar...I only want to make one change at a time anyway so I can keep track of whats doing what...and if temps remain an issue after repalcing the thermostat I will give the Two 2 Cool a go.

I have spoken to a couple more people regarding the 2 cool that use it in thier enduro bikes (they are racers that do a lot of riding) and they have said they have been using the product for over a year in their bikes and they have noticed no related wear or ill affects.
 

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lee said:
J........
I am going to add some of this two2cool to my oil and see what shakes out. It works or it doesn't. Either way no harm done. So chew on it boys.
Lee - let us know how it went down.

On my R, my observation is that it runs about 10-15F (5-8C) hotter than my other bikes (including the Brutale S).

The other day, I was cruising on the freeway at about 60mph (100kph) with about 60F (15C) ambient temperature and the bike was reading about 195F (90C) while cruising with all the cool wind ... I thought that was really high for a perfectly good bike, and particularly while I'm running the bike in and keeping the revvs low (well, at least trying really hard to :) )

I do wish there is a solution, as I'm worried about what kind of temps the bike will be showing (super high for sure) when the summer comes along.

PS--- what is your bike??
 

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fazer6 said:
I think Mike was meaning that it makes sense that when the engine is running at higher rpm, it generates more heat, thereby requiring more coolant flow from the faster spinning of the water pump, rather than the constant speed of an electric, regardless of engine rpm?
Yes, that is exactly what I meant-thanks. :)

Stopping a water pump with the engine still generating heat is not a good idea, the water still needs to circulate around the engine to allow the hot water to open the thermostat, Ducati's allow a flow past the stat and through the radaitor head tank (they have inlet and outlet on one side, so the rad is a 'double pass' affair, they allow the water to seep past the divider in the head tank until the stat opens which increases the flow causing the water to travel across the rad) all cars have a by-pass to allow the circulation of water. :)
 

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Discussion Starter #16
sig scuro,

My bike is Tambo # 136. Nothing like screwing around with a 43 K bike eh? But when you get right down to it it's just a fancy F4.

Re: the bypassing of coolant comment. Cag had a post about drilling holes in the thermostat to allow coolant to constantly pass through. I wonder if that would achieve the same effect as the Duc setup. I have a 1098 and in the heat of the summer the worst I've ever seen was 204-205 F in traffic and 180-185 at speed. Course it's a diff eng layout which I think makes a diff.
 

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mikef4uk said:
Yes, that is exactly what I meant-thanks. :)

Stopping a water pump with the engine still generating heat is not a good idea, the water still needs to circulate around the engine to allow the hot water to open the thermostat, Ducati's allow a flow past the stat and through the radaitor head tank (they have inlet and outlet on one side, so the rad is a 'double pass' affair, they allow the water to seep past the divider in the head tank until the stat opens which increases the flow causing the water to travel across the rad) all cars have a by-pass to allow the circulation of water. :)
Right, but if you are talking about a thermostat-less system you no longer need to circulate the coolant to open the thermostat. I would relocate the temperature sensor (thermistor) to the block so that you know when to turn the pump back on. Again, all a thought exercise since pretty much everybody uses a mechanical water pump and thermostat so there is probably something I missing.
 

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lee said:
Just got off the phone with a guy from "Two2cool". Here's some food for thought. The oil/coolant heat exchanger transfers heat from one to the other. Oil temps generally run hotter than coolant. Therefore the oil is heating the coolant, particularly in traffic and at rest. Could this be part of the problem? If I could find the space I would totally remove that exchanger and install a dedicated oil cooler. We also discussed the water pump situation. Speeding up the flow of coolant is not necessarily the best thing to do as there is a certain optimum "dwell" time of the coolant in the rad to extract the most heat vs not enough flow to cool the engine. Airflow vs coolant flow. Where's the optimum point?

I am going to add some of this two2cool to my oil and see what shakes out. It works or it doesn't. Either way no harm done. So chew on it boys.
I think what the guy at Two2cool is correct in what he is saying and I have no doubt if you were to install a dedicated oil cooler It would solve the excessive heat problem, :mad: and who knows, it may also solve the "big end" problem as well. :jsm: As for the flow rate of the coolant, there is a optimum flow rate however, rule of thumb is, if the water flow rate is too slow a radiator / engine can suffer from lamina flow rate, which greatly reduces the radiators efficiency. The flow rate must be great enough to create a turbulent flow rate, however this is not to say the greater the flow rate the better, there is a point were you can increase it all you want and it still won't make any difference. As long as you have created a turbulent flow, that's all you need. This could be one of the reasons that the new water pump impellor, some people have installed helps with the over heating problem, it just increases the coolant flow rate at low revs, which creates a better turbulent flow. :jsm:
 

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Rockethouse said:
:ahhh: :ahhh: :ahhh:

http://mvagusta.net/forum/showthread.php?t=13266


With regards to the coolant flow I suggested that (in the impellar fix thread http://mvagusta.net/forum/showthread.php?t=12565&page=14&pp=10 ) that the 636 impellar may be slowing the coolant flow rather than speeding it up (which now another highly experienced race mechanic has said he used to do for race bikes...either way it appears that the coolant flow via the OEM impellar may not optimal...with the modded impellars soon to be on thier way we should have an answer.

I'm going to hold off putting the 2 cool in my bike as engine temps were not an issue for me until recently and it appears that they are a result of a thermostat on the way out so I'll change that and see what happens with the new impellar...I only want to make one change at a time anyway so I can keep track of whats doing what...and if temps remain an issue after repalcing the thermostat I will give the Two 2 Cool a go.

I have spoken to a couple more people regarding the 2 cool that use it in thier enduro bikes (they are racers that do a lot of riding) and they have said they have been using the product for over a year in their bikes and they have noticed no related wear or ill affects.

Opppssss, sorry i had missed that thread :wtf:
 
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