Oil Cooler Effectiveness

[x01660]

So I'm planning on taking a camping trip out to Death Valley in April or May, which is right around the time daytime temps start to hit 100 +. Now I'm not worried about me (I lived in Sudan for 4 years, and I'm used to the heat), but I'm wondering how my air/oil cooled GS will do in that heat. So, how effective is the bike stock in that temperature range, or should I get an oil cooler? Or should I just avoid the desert altogether with an air/oil cooled bike?

Also, what recommendations do y'all have for keeping cool in the desert on a motorcycle? Or rather just being safer? Thanks.


-x01660

 

[CivilRock]

What kind of bike do you have?
What if any mods have you made?
Do you have a oil temp gauge on board?
Do you have a IR temp gauge?

Without knowing anything about you or your bike, I would say you'll be fine. There's millions of oil cooled bikes that operate just fine in hot weather.

Don't let the oil get over 250F and you'll be fine. Buy a $12 IR temp gauge from Harbor Freight and check it on your trip.

I bought a 1995 GSX600 Katana oil cooler from ebay for $29 and fitted it to my bike without too much hassle. But I plan on some heat producing modifications in the future, and I needed something to fill the oil ports in the motor anyway.

-Kevin

 

[x01660]

What kind of bike do you have?
What if any mods have you made?
Do you have a oil temp gauge on board?
Do you have a IR temp gauge?

Without knowing anything about you or your bike, I would say you'll be fine. There's millions of oil cooled bikes that operate just fine in hot weather.

Don't let the oil get over 250F and you'll be fine. Buy a $12 IR temp gauge from Harbor Freight and check it on your trip.

I bought a 1995 GSX600 Katana oil cooler from ebay for $29 and fitted it to my bike without too much hassle. But I plan on some heat producing modifications in the future, and I needed something to fill the oil ports in the motor anyway.

-Kevin

I've got a 84 GS 1150E, and I do have a temp gague on the cluster.


-x01660

 

[posplayr]

For big block bikes, you get a big benefit in operating temperature by going to a Series R/R.
Read about it here.

You should be able to find Chefs posts for which he just installed a Compufire on his 1229.

http://www.thegsresources.com/_forum/showthread.php?t=161397

 

[CivilRock]

Doesn't your bike already have an external remote oil cooler? Are you asking if you need a bigger one?

If you're running stock, the bike will be fine.

I don't do well in the heat at all. I prefer 35F to 90F. But I've ridden in 125F+ heat a ton racing supermoto and road racing (track temps of 140F). It gets amazingly hot in full leathers with a fire breathing beast under you while you're doing the equivalent of running a marathon. Also have done several cross country rides (OR to FL and back) in what I would call tremendous heat. TX in the summer is brutal. Best thing ever is just to soak down my T-shirt (and underwear) with water and carry a 2 liter camelback to keep hydrated. I bought some no-name backpack online with a 2 liter bladder for $14 years ago, and use it all the time. I remember one time taking a mouth full of water out of the camel back and just letting it dribble out of my mouth onto my chest it was so freaking hot.

In one answer: Lots of Water.

-Kevin

 

[rustybronco]

You might just be able to get away with a good synthetic oil. One that can handle the heat without breaking down.

Check bobistheoilguy.com

http://www.bobistheoilguy.com/motor-oil-101/

 

[x01660]

For big block bikes, you get a big benefit in operating temperature by going to a Series R/R.
Read about it here.

You should be able to find Chefs posts for which he just installed a Compufire on his 1229.

http://www.thegsresources.com/_forum/showthread.php?t=161397

I'll have to scope it out.

Oh, and it's Zak, BTW, Jim...


-x01660

 

[posplayr]

I'll have to scope it out.

Oh, and it's Zak, BTW, Jim...


-x01660

Ok Zak, did not jump out at me.

Then ask Bill about which comes first, cooler or Series R/R. :-\\\


If you are worried about it, there are small 550 cooler on ebay for cheap that will fit with a little bit of stretching. I might even have one complete one if I put the 1150 cooler on mine. You would just need banjo bolts and to plug the cover.

This is basically what is on my 1166. It used to run warm, but with the Series R/R it usually does not go above 210 DegF; 220DegF max.


http://www.ebay.com/itm/Suzuki-GS-G...Parts_Accessories&hash=item23357216fb&vxp=mtr

I'm just concerned about the Tucson Summer heat. It is beautiful 70-80's now, but ...........

 

[Guest]

They are effective
I showed you the cooler I was going to install on your engine.
Motor
83 GS1100E, 1150 crank, 1150 barrels, .5 over pistons and stock head with cut intake valves.

 

[x01660]

They are effective
I showed you the cooler I was going to install on your engine.
Motor
83 GS1100E, 1150 crank, 1150 barrels, .5 over pistons and stock head with cut intake valves.

You are so epically awesome, I can't even alliterate it with words.


-x01660

 

[ArttuH]

For big block bikes, you get a big benefit in operating temperature by going to a Series R/R.
Read about it here.

You should be able to find Chefs posts for which he just installed a Compufire on his 1229.

http://www.thegsresources.com/_forum/showthread.php?t=161397

I know this has been debated here earlier and there is also some empirical evidence but I still have hard time believing that the regulator could drop engine temp significantly.

Maximum power output of the generator is about 250W so I think in the worst case the stator can produce about 250-300W heat power. On the other hand at steady 60mph speed the engine probably produces about 10-20kW mechanical power. Rule of thumb says that one third of total energy of consumed fuel goes out with the exhaust gases, one goes to heat to the engine and the rest to the mechanical power. So then total heating power to loose through engine cooling would be around 10-20kW. Compared to this 300W from the stator is pretty much negligible.

Situation might be slightly different at low speed city traffic or when the engine is idling. Then total heat power produced by the engine is significantly lower and also cooling is less efficient due to slow air flow. In this case the stator heat power may have noticeable part in the engine thermal balance.

Any ways, this is quite interesting topic. Maybe I should experiment this by myself too. Do I recall correctly that there are some OEM series regulators available for reasonable money, made by Shindengen? That could be worth of trying.

 

[Guest]

I know this has been debated here earlier and there is also some empirical evidence but I still have hard time believing that the regulator could drop engine temp significantly.

Maximum power output of the generator is about 250W so I think in the worst case the stator can produce about 250-300W heat power. On the other hand at steady 60mph speed the engine probably produces about 10-20kW mechanical power. Rule of thumb says that one third of total energy of consumed fuel goes out with the exhaust gases, one goes to heat to the engine and the rest to the mechanical power. So then total heating power to loose through engine cooling would be around 10-20kW. Compared to this 300W from the stator is pretty much negligible.

Situation might be slightly different at low speed city traffic or when the engine is idling. Then total heat power produced by the engine is significantly lower and also cooling is less efficient due to slow air flow. In this case the stator heat power may have noticeable part in the engine thermal balance.

Any ways, this is quite interesting topic. Maybe I should experiment this by myself too. Do I recall correctly that there are some OEM series regulators available for reasonable money, made by Shindengen? That could be worth of trying.

I saw the difference when my temperature gauge stopped climbing to the spot with the shunting R/R.
I was pleased as punch since my bored out engine runs hot and I am very open to trying ways to keep it cool.
It worked!

 

[tkent02]

I'm so curious about this, just bought a series regulator for my 550, whats on there now is a big Shendigan shunt unit. I'm going to rig it so I can switch back and forth on the fly. Ride a while on the series one, then switch to the shunt to see what the oil temp does.

Still need to figure out what to use for a temp gauge… Any ideas?

 

[posplayr]

I know this has been debated here earlier [#1]and there is also some empirical evidence but I still have hard time believing that the regulator could drop engine temp significantly.

[#2]Maximum power output of the generator is about 250W so I think in the worst case the stator can produce about 250-300W heat power. On the other hand at steady 60mph speed the engine probably produces about 10-20kW mechanical power. Rule of thumb says that one third of total energy of consumed fuel goes out with the exhaust gases, one goes to heat to the engine and the rest to the mechanical power. [#3]So then total heating power to loose through engine cooling would be around 10-20kW. Compared to this 300W from the stator is pretty much negligible.

Situation might be slightly different at low speed city traffic or when the engine is idling. Then total heat power produced by the engine is significantly lower and also cooling is less efficient due to slow air flow. In this case the stator heat power may have noticeable part in the engine thermal balance.

Any ways, this is quite interesting topic. Maybe I should experiment this by myself too. Do I recall correctly that there are some OEM series regulators available for reasonable money, made by Shindengen? That could be worth of trying.

[1] "some empirical evidence" would be better characterized by "direct measurement" and "independent" verification. :|

[2]Firstly, your power analysis is somewhat simplified as it does not consider the hidden power dissipated in the stator, only the power being delivered to the load (how high of a temperature do you think an oil bathed stator needs to be to burn the thermal epoxy off of it???). It is stator power that heats the engine and not delivered power. As I have measured, calculated, plotted and posted. There is a big difference. A shunting R/R is dissipating more power in the stator than it is delivering. Based on that analysis, the SHUNT R/R dissipates about 350 watts in the stator while the Series only 125W. That is a total of 225W or a 1/3 of a hp.

[3]Second, despite how amazing it might be, the convective heat flow from the engine is proportional to the temperature differential between the engine and the ambient air. Air is not a particularly good conductor of heat and most of the heat is going out the tail pipe. So with what is left over and if there is any added heat to the engine you have to stretch the temperature differential between engine block and ambient to get rid of it. So in nominal numbers if ambient is 25degC and you are running at 135 degC that is a 110 degC difference. It only takes a 10% drop in heat dissipation to drop the temperature 10% of 110 or 11 degC (30 degF). That is what I saw on my CV 1166.

For a large cc motor, it really is much more of a thermal balancing act for what amounts to only relatively few therms. This conclusion is based on direct evidence of the temperature drops.

Put a Series R/R in and you will find out. I'm sure with your supercharger, you have a "super-charred" stator and elevated oil temps despite your northern clime.

 

[ArttuH]

[1] "some empirical evidence" would be better characterized by "direct measurement" and "independent" verification. :|

[2]Firstly, your power analysis is somewhat simplified as it does not consider the hidden power dissipated in the stator, only the power being delivered to the load (how high of a temperature do you think an oil bathed stator needs to be to burn the thermal epoxy off of it???). It is stator power that heats the engine and not delivered power. As I have measured, calculated, plotted and posted. There is a big difference. A shunting R/R is dissipating more power in the stator than it is delivering. Based on that analysis, the SHUNT R/R dissipates about 350 watts in the stator while the Series only 125W. That is a total of 225W or a 1/3 of a hp.

[3]Second, despite how amazing it might be, the convective heat flow from the engine is proportional to the temperature differential between the engine and the ambient air. Air is not a particularly good conductor of heat and most of the heat is going out the tail pipe. So with what is left over and if there is any added heat to the engine you have to stretch the temperature differential between engine block and ambient to get rid of it. So in nominal numbers if ambient is 25degC and you are running at 135 degC that is a 110 degC difference. It only takes a 10% drop in heat dissipation to drop the temperature 10% of 110 or 11 degC (30 degF). That is what I saw on my CV 1166.

For a large cc motor, it really is much more of a thermal balancing act for what amounts to only relatively few therms. This conclusion is based on direct evidence of the temperature drops.

Put a Series R/R in and you will find out. I'm sure with your supercharger, you have a "super-charred" stator and elevated oil temps despite your northern clime.

[2] Yes, it was simplified analysis since I was interested to get just a ballpark figure to estimate scale of heating power from the stator. So I can easily believe if you say it's 350W with a shunt regulator. However, this is a worst case situation when there is no load from the charging system and the regulator shunts everything to the stator, right? And when the load increases difference between the shunt and series regulators gets smaller.

[3] Correct. But based on my knowledge the total heat dissipation of the engine is approximately the same than the mechanical output power. So at 60mph cruising speed the heat dissipation would be about 10-20kW. Therefore that 10% reduction would be at least 1kW.

Actually I had a series R/R some years ago. I designed one when my original R/R went dead. I can't recall noticing any difference in oil temps with it though I wasn't specifically watching that. But I'm sure there wasn't 10?C drop, few degrees might have got away unnoticed. Later on when my series R/R broke and I changed to FET shunt R/R I also changed the whole engine at the same time so I couldn't compare temps.

But yes, it would be interesting to try again. I know very well that shunt regulators aren't too healthy for the stator so upgrade would make sense just because that. On the other hand my bike has quite a lot of electric load so probably difference wouldn't be that big.

 

[posplayr]

[2] Yes, it was simplified analysis since I was interested to get just a ballpark figure to estimate scale of heating power from the stator. So I can easily believe if you say it's 350W with a shunt regulator. However, this is a worst case situation when there is no load from the charging system and the regulator shunts everything to the stator, right? And when the load increases difference between the shunt and series regulators gets smaller.

[3] Correct. But based on my knowledge the total heat dissipation of the engine is approximately the same than the mechanical output power. So at 60mph cruising speed the heat dissipation would be about 10-20kW. Therefore that 10% reduction would be at least 1kW.

Actually I had a series R/R some years ago. I designed one when my original R/R went dead. I can't recall noticing any difference in oil temps with it though I wasn't specifically watching that. But I'm sure there wasn't 10?C drop, few degrees might have got away unnoticed. Later on when my series R/R broke and I changed to FET shunt R/R I also changed the whole engine at the same time so I couldn't compare temps.

But yes, it would be interesting to try again. I know very well that shunt regulators aren't too healthy for the stator so upgrade would make sense just because that. On the other hand my bike has quite a lot of electric load so probably difference wouldn't be that big.

[2a] I tried to be pretty specific; but here goes again 350 watts is what is dissipated in a stator using a shunt regulator when full load of 15 amps (220 watts) is delivered to the electrical system. With LED's it gets worse. With a fuel pump it goes lower.

[3] I am not offering a quantitative technical analysis of the heat flow, just showing that the apparent large disparity between engine power relative to stator power coupled with a drop in temperature is not as inconsistent as it might initially appear. Even your 1K watt estimate is only 4 times what I measured (250 watts). I'm sure if you sharpen your pencil, you will be able to figure out that the actual amount of convective heat flow from the engine (what heats the oil) is not nearly as much as one would suspect and that in fact the strata power can make more that just a perceptible difference, but make 20-30 degF difference.

The phenomena has been documented and confirmed by multiple sources. Off the top of my head, the people that I know who can independently confirm this are:
Katman, WheatDog , Chef1366 and myself.

All of these people have had sufficient experience riding their own big block GS1100 which have OEM fitted temp gauges (or other) to recognize when their temperature gauges drop after an install of the Series R/R. To my knowledge all of these have been with the Compufire and not the SH-775 but I would gather it does the same.

When you say you designed a Series R/R, I'm not sure if you mean an R/R that performs like these I mention or something else. I'm guessing not or else you would have seen a difference for your size motor.

 

[ArttuH]

The phenomena has been documented and confirmed by multiple sources. Off the top of my head, the people that I know who can independently confirm this are:
Katman, WheatDog , Chef1366 and myself.

All of these people have had sufficient experience riding their own big block GS1100 which have OEM fitted temp gauges (or other) to recognize when their temperature gauges drop after an install of the Series R/R. To my knowledge all of these have been with the Compufire and not the SH-775 but I would gather it does the same.

I'm not doubting your findings. I'm just wondering what is the actual mechanism of the temperature drop.

When you say you designed a Series R/R, I'm not sure if you mean an R/R that performs like these I mention or something else. I'm guessing not or else you would have seen a difference for your size motor.

I think it was equivalent in this sense. It was basically a controlled rectifier bridge and it wasn't doing any current shunting. The engine was stock when I installed it, if that matters anything.

Any ways, I think we have side railed this topic enough already If I can find a SH-775 for reasonable money I will try this during next summer. But if you have any proper reference about heating power of typical motorcycle engine it would be interesting to hear. I have seen just some rough values but usually they suggest that energy loss through cooling is at the same level with outputted mechanical power.

 

[posplayr]

I'm not doubting your findings. I'm just wondering what is the actual mechanism of the temperature drop.


I think it was equivalent in this sense. It was basically a controlled rectifier bridge and it wasn't doing any current shunting. The engine was stock when I installed it, if that matters anything.

Any ways, I think we have side railed this topic enough already If I can find a SH-775 for reasonable money I will try this during next summer. But if you have any proper reference about heating power of typical motorcycle engine it would be interesting to hear. I have seen just some rough values but usually they suggest that energy loss through cooling is at the same level with outputted mechanical power.

Sorry to be a little snippy but there have been several people questioning the results in fact wanting back to back testing. This is even after multple independent confirmations. Sorry after riding a bike for 10k miles I know how it runs and can clearly see the change and there is no reason to go back.



A firing angle controlled 3phase scr bridge would be what the sh775 and the cycle electric are. The compufire uses mostest to perform synchronous rectification. Transition in the cf seem to be at voltage/current zero crossing to minimize transients.

I did detailed stator currents measurements using current clamp and digital scope. I estimated power based on average current and known coil resistance. With some three phase calculation I derived total stator power.


These air cooled bikes have little reserve capacity for cooling, the relatively small stator power causes a surprising large temp differential to get the extra heat out.

 

[Nessism]

Count me as another with questions about how much effect the R/R has on oil temp. There is no direct oil flow onto the stator for one thing, so even if it's running hot, how much contact does it have with the sump oil? There is splash lubrication to the stator, but how much oil volume contacts it, and how much could that affect the sump oil temp? Also, lets not forget that in order to heat the oil the stator temp must be higher than the oil itself. So with a typical air cooled engine that's running at say 225F, the stator temp would have to be above this temp in order for heat to be added to the oil. Are you guys suggesting the stator is running upwards of 300F due to shunting current? On my 1000S the oil temp gets up into this range on a hot day. Having a hard time getting my mind around the stator contributing to this.

 

[posplayr]

Count me as another with questions about how much effect the R/R has on oil temp. There is no direct oil flow onto the stator for one thing, so even if it's running hot, how much contact does it have with the sump oil? There is splash lubrication to the stator, but how much oil volume contacts it, and how much could that affect the sump oil temp? Also, lets not forget that in order to heat the oil the stator temp must be higher than the oil itself. So with a typical air cooled engine that's running at say 225F, the stator temp would have to be above this temp in order for heat to be added to the oil. Are you guys suggesting the stator is running upwards of 300F due to shunting current? On my 1000S the oil temp gets up into this range on a hot day. Having a hard time getting my mind around the stator contributing to this.

Ed,
I'm baffled by this question.

How do you think stators turn into crispy critters?

Jim