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Left Fan install on 2014 R1200RT-LC

chrismiii

R1100RT,K75,Burgman650
For anyone interested on a 2014 R1200RT-LC I recently installed a radiator fan on my left radiator. It’s just one I located on EBay off a GS. The part numbers are same for the RT and GS. The fan mates right up to the left radiator as it does same on the right side –only need to shave off the left radiator cowling a few millimeters. The electrical bus cannot accept the additional fan – unless one installs a relay in the circuit –simple do if you wish them both to cycle on and off together. I didn’t want mine wired that way primarily because I wished a manual waterproof switch. I wanted control over the additional fan to keep the heavy work off the primary stock fan in hot weather, traffic, etc. This last UT MOA made me worry. I went south to the Grand Canyon and the other parks in 100 heat what if the ONLY fan quits? So now no more worries – got some level of redundancy like the Boeing 878 I fly! Anyone interested I’ll post some pictures – again easy project and I feel very worth while myself.

Link to your address bar:

https://photos.google.com/share/AF1...?key=Qlk2OGFiMzdhcWVoZ0E1dG1WWXQ1bVhqeDZfbzZR

https://photos.google.com/share/AF1QipNzAQAjMfQPQzjUl4moWrquNTug7--rxIrsSQl-hgu4B3WomdkNVAHLJkcD2YV-hw?key=Qlk2OGFiMzdhcWVoZ0E1dG1WWXQ1bVhqeDZfbzZR
 
Well, I live in southern AZ and I have yet to see, or hear of, any model of water cooled BMW having overheating issues (including mine). Me thinks your mod is "belt-and-suspenders" but if it keeps you happy, good for you!
 
For anyone interested on a 2014 R1200RT-LC I recently installed a radiator fan on my left radiator. It’s just one I located on EBay off a GS. The part numbers are same for the RT and GS. The fan mates right up to the left radiator as it does same on the right side –only need to shave off the left radiator cowling a few millimeters. The electrical bus cannot accept the additional fan – unless one installs a relay in the circuit –simple do if you wish them both to cycle on and off together. I didn’t want mine wired that way primarily because I wished a manual waterproof switch. I wanted control over the additional fan to keep the heavy work off the primary stock fan in hot weather, traffic, etc. This last UT MOA made me worry. I went south to the Grand Canyon and the other parks in 100 heat what if the ONLY fan quits? So now no more worries – got some level of redundancy like the Boeing 878 I fly! Anyone interested I’ll post some pictures – again easy project and I feel very worth while myself.

Link to your address bar:

https://photos.google.com/share/AF1...?key=Qlk2OGFiMzdhcWVoZ0E1dG1WWXQ1bVhqeDZfbzZR

https://photos.google.com/share/AF1QipNzAQAjMfQPQzjUl4moWrquNTug7--rxIrsSQl-hgu4B3WomdkNVAHLJkcD2YV-hw?key=Qlk2OGFiMzdhcWVoZ0E1dG1WWXQ1bVhqeDZfbzZR

Smart thinking!

I had a fan installed on my '05 R1200RT, to address heating issues on hot days in thick traffic.

With Global Climate Change rolling the dice these days, a little extra protection is prudent. :thumb
 
I think you have a great idea, always wondered if the Police spec bikes have a second fan
Will be looking for parts this winter
 
My concern would be that by adding a second fan you reduce the air flow over the radiators at speed. That might result in your bike actually running warmer at speed until you trip the fans. I think your fans will run more frequently and for a shorter period of time.

I used to work aircraft and I totally get the redundancy thing, especially when I happen to be flying. But if your single fan quits on your motorcycle, you won’t fall out of the sky. But losing a fan could be inconvenient.

Thanks for the write up.
 
My concern would be that by adding a second fan you reduce the air flow over the radiators at speed. That might result in your bike actually running warmer at speed until you trip the fans...
That is absolutely the case.
It is my understanding that even the the addition of radiator stone guards such as the Touratech, etc., type, restrict airflow slightly and have been demonstrated to raise the coolant temperature quicker than without that restriction. These are fairly small rads afterall and the entire system has been designed to work properly. That doesn't mean that BMW hasn't made engineering mistakes in the past and won't in the future, but these systems are now 3-4 years old with some riders having already racked up 100,000~ miles in all kinds of conditions including the desert and this has not been raised as an issue that I'm aware of.

What the pictures of the second fan suggest to me is that you have introduced a problem to fix an issue that does not exist. All while reducing airflow over the radiator which will absolutely push the bike to need the fan(s) more than stock. This also introduces another electrical circuit, therefore another potential failure point, for no demonstrable benefit.

The first rule of reliability is to make as much/many of your systems a) simple and b) passive. The second fan will definitely reduce unaided airflow through the left radiator. Introducing needless strain on a system is never good.

... I used to work aircraft and I totally get the redundancy thing, especially when I happen to be flying. But if your single fan quits on your motorcycle, you won’t fall out of the sky...
Redundancy is a necessity for safe operato of an aircraft, but like you say, not really an issue for this bike that I've heard of or experienced. I used to carry spare spark-plugs and other gear when I was riding bikes in the 70's but carry very little now as I feel it is a complete waste of time. Outside a tire inflator, tubeless repair kit, some top-up oil, and a few other items, the rest is needless.

No bike is completley bullett-proof, but these are pretty good and any failure is likely going to be too hard to predict to actually be prepared with redundencies, spares, etc.

Ride it and don't fix things that aren't broken. Enjoy the ride and relax.

... I think the bike is only like 20% water cooled ...
It seems that it is a bit closer to 35%. The press releases stated that air cooling had been reduced to 65% with the remainder handled by water-cooling.

... If the fan died you still have coolant running through the head ..., if you loose a water pump then you may have a issue ...
Absolutely. Losing a water-pump would be very serious.

Losing your rad fan simply means you would have to avoid extended preiods of riding below 20-30~ mph. I rode across the Continental Divide on my way to the SLC MOA Rally last year in 100-F + weather at close to and into triple-digit speeds a lot of the time with only stopping twice for gas (fuel-economy suffers at high speeds) and one 25-minute stop for lunch on the last day, without any issue. After the Rally, I took the bike to the Bonneville Slat Flats and ran at tripe-digit speeds for extended periods without any issue.
 
Air flows through a radiator. Restricting flow could happen either on the front or the rear of one.
 
I agree with lFarling, with the fan on the back side it wouldn't restrict much if any airflow. I believe the authority bikes have a second fan. If the fan was restrictive without benefit why have a fan in the first place? I personally have no need for a second fan. My riding is 100% pleasure, living in the country it's rare that I ever deal with traffic. I have about 25k on the bike I may of hit 7 bars, but that didn't last but a minute.

The bikes cooling ability's are good, if you have ridden an airhead, oilhead, hexhead, camhead you'd agree it's far better. It also keeps the bike at a more consent temperature, and I think that helps keep the valves from needing adjustment.

Jay
 
Well the fan is on the back side of the radiator so I see know way it could impede air flow at all so not an issue...
I agree with lFarling, with the fan on the back side it wouldn't restrict much if any airflow...
Please do not take this the wrong way, but, unfortunately, you are both making assumptions without appearing to know enough about cooling systems to do so. This is how mis-information spreads and it does no one a service. Figures I have seen suggest that there is about a 15%-20% improvement in having the fan behind (a puller) versus in front (a pusher), so it generates 80%-85% of the restriction in behind vs in-front.

As "azgman" correctly pointed out, it does not matter whether the fan is in front of or behind the rad, it does impede air-flow and cooling. I was not quantifying the exact amount of restriction. The shroud is even more so. There are many systems with the fan in front of the rad (pusher-fan) mostly for packaging issues. The fan is best placed behind the rad (puller-fan) where possible because the thermal exchange is more efficient if the air is drawn through the rad versus being pushed through. The fan shroud plays a significant role here as well, but it is always a compromise between having the most efficient fan operation (a completley enclosed fan shroud) and the desire to have a cooling system that does not rely on the fan for most of it's operating life.

... As far as another problem if you put a switch on it and run it from a fuze block just not an issue as far as causing another issue or introducing a reliability issue.

The idea is sound with no drawback except for the cost of implementing it. And of course you need to remove another fan to flush and clean the radiator from the rear...
Please explain to me how introducing putting "a switch on it and run it from a fuze block" could ever be considered "not an issue as far as causing another issue or introducing a reliability issue". You are suggesting that switches never fail and that connections never fail. Both of these assertions have absolutely no basis in fact and are incorrect on every front. Anything that is added to a system such as another electrical connection or another switch absolutely introduces an additional "potential" failure point. This is so basic that it defies logic that anyone would suggest otherwise.

... You mention rad guards on the out side of the radiator. With a heat gun one on and one off I found no difference. I ran them took them off, installed one and ran it for awhile and found no difference on the back side on the water hoses in temp with a throttle chop and pull over on the road to check, and then installed the second one on the fan side. My gauge shows the same bars with or without...
This is apples-to-oranges.

First, from what you've already mentioned, I will presume you are using a run-of-the-mill infrared pyrometer and not a probe-type pyrometer and obviously not a sensor (the only real way to measure coolant temperature with any accuracy). There is no way for you to get accurate readings from that. A pyrometer that displays "bars" and not actual degress is absolutely useless for this application. First, you have bars which identify a range of temperature, not an actual temperature. Second, a pyrometer that does not display an actual temperature is unlikely to provide in it's documentation, a figure for the "dampening" value of it's readout, therefore, you have two significant factors that will only identify that the air outside the rad is roughly the same. Well, I would have guessed that they would be very close, because it is the coolant temperature, that we are talking about, not the outside air next to the rad.
Even the coolant temperatures should be very close with or without the rad protector. I only said that the guards "restrict airflow slightly and have been demonstrated to raise the coolant temperature quicker than without that restriction". All of your "testing" does nothing to counter that, nor could it without proper sensors and intrusmentation or data-logging. It is very easy to demonstrate what I have mentioned with a short sesson of proper data-logging using the right software. The water-cooled R-bikes have all the sensors needed and collect all of that data already in an accurate and relaible manner. You were measuring the ambient air surrounding the rad after it had stopped (differences would be significantly reduced) with a very blunt and imprecise instrument (differences would be difficult to identify).

As for using a heat-gun, I don't think that will tell you much at all.

Yes, they can generate a heat of 1,000-F~ but that is at their tip not what is hitting the radiator 4"-6" away. The vast majority of these guns run 20-25 cfm tops (IIRC, my body-work grade professional one is 28 or 32 cfm), they all generate far less than that 4"-6" away from the tip. Haven't worked the math but that might be something like eqal to 2-10 mph so the effect is minimal. Just as it seems I need to be riding at something above 10-15 mph with unobstructed air for the fans to shut-off (take heat out of the system) you would need to do somewhat similar speeds to push any amount of heat into the system.

It appears you are likely using this as a pusher without a shroud, not a shrouded puller. So the actual cfm, temperature, and heat transfer is going to be far, far less. The very minimum your typically look at for an auxillary 4" cooling fan is 120-150 cfm which is likely 10x the effective heat-gun cfm. So the heating effect of the gun on a system already up to temperature with the water-pump running should be negligible unless we are talking about a prolonged period.

Remember, the entire cooling system is designed to remove heat, not to put it back in, so it is far, far harder to add heat to the engine with a fully operational cooling system than it is to remove it. The heat-gun demonstrates absolutely nothing other than what affect a heat-gun will have.

... I believe the authority bikes have a second fan...
The "Authority" bikes do not have a second fan. There is no need for one. The existing cooling system works fine, even in stop and go traffic. Yes, the fan comes on and in traffic jams will run virtually continously, but that happens with virtually every vehicle, you just don't hear it in a car. It is doing what it was designed to do, and within it's design parameters.

... If the fan was restrictive without benefit why have a fan in the first place? ...

Sorry Jay, I might not have been as clear as I should have been. I wasn't meaning to say that the existing OE-fan (right-side) was without benefit, just that the addition of a left-side fan provided "no demonstrable benefit". What I mean by that is that if the existing system (one fan on the right rad) is sufficient to avoid overheating in all "practical" applications, including the police bikes which idle for extended periods of time and have the exact same 1-fan system, than adding a second, un-needed fan provides "no demonstrable benefit".

The OP added a second fan as an insurance policy against:
  • overheating in traffic with high outside temps - I've not heard of any CHPs bikes having overheating issues, but perhaps they have
  • the first fan failing - not heard of any of these fans failing and in well over 1 million miles of driving and several years of racing cars and trucks, I have had many failures, including 3 BMW engines, but never an electric fan failure.
Adding failure points to protect against something that has not been shown to exist, is not good policy. Especially when the OE-fan failure would only limit your ability to run the bike in traffic-jams but you'd still be able to ride it fine to a dealership or home, in 100-F weather outside that one limitation.
 
<snip>

[*]the first fan failing - not heard of any of these fans failing and in well over 1 million miles of driving and several years of racing cars and trucks, I have had many failures, including 3 BMW engines, but never an electric fan failure.

Alan must have never owned a BMW K75 or K100. These cooling fans failed with predictable regularity. Hopefully the new models have better fan motors.
 
Alan must have never owned a BMW K75 or K100. These cooling fans failed with predictable regularity. Hopefully the new models have better fan motors.
You're correct Paul, I didn't. I have had water-pumps fail on me (one Ford and one BMW). I have cracked cylinder heads, dropped valves, put holes in pistons, had rads leak, had cars with too weak a cooling system, etc., but have never had an electric rad fan die on me. I have had a rad fan expand so much from the heat that it was hitting the fan-shroud, and a clutch fan fail (but they fail in the on-position which is fine), but that's it.

BMW like other manufacturers is known to have made many engineering mistakes over the years. We all know about the FDs of some models, and their cars have also had many issues but I did say that we are now 4-5 years into this engine with plenty running good mileage (more than enough time/mileage for weaknesses to be seen) and no indication of any issue that I'm aware of. Is anyone aware of an issue with these?


LFarling, I don't believe that I said (didn't mean to) that a second fan would hurt anything, just that it would put more load on the system, and that it was fixing a problem that there was no evidence existed.

Again, one has to be careful in making sure conclusions are drawn from the correct areas. The OE fan does restrict flow, however, it is necessary and, when operating, increases airflow far more than it restricts it. A second fan would only be needed if the OE-fan did not have the capacity to remove sufficient thermal-load from the rad, or if the OE-fan had shown any suggestion of being suseptible to failure. AFAIK, neither of these two criteria exist, so a second fan is of no practical benefit.

All the laser does is give you placement so that it is repeatable. It doesn't change the fact that what is being used to measure the differences is not capable of doing so from outside the system in the manner you described. As simple example is that many after-market oil temperature sensors placed inside the engine are quite worthless because they are placed in the wrong spot internally and therefore cannot measure what needs to be measured due to the cooling and merging effects of the system. Using something outside the system is even less meaningful and an infared pyrometer (laser or not) will tell very little if anything, so I'm not surprised that there was little or no difference in the readings. I would not expect there to be under those conditions.

Like you say, to each their own. I do things that some think aren't necessary and I don't do things that some swear must be done. Ride safe.
 
You're correct Paul, I didn't. I have had water-pumps fail on me (one Ford and one BMW). I have cracked cylinder heads, dropped valves, put holes in pistons, had rads leak, had cars with too weak a cooling system, etc., but have never had an electric rad fan die on me. I have had a rad fan expand so much from the heat that it was hitting the fan-shroud, and a clutch fan fail (but they fail in the on-position which is fine), but that's it.

BMW like other manufacturers is known to have made many engineering mistakes over the years. We all know about the FDs of some models, and their cars have also had many issues but I did say that we are now 4-5 years into this engine with plenty running good mileage (more than enough time/mileage for weaknesses to be seen) and no indication of any issue that I'm aware of. Is anyone aware of an issue with these?


LFarling, I don't believe that I said (didn't mean to) that a second fan would hurt anything, just that it would put more load on the system, and that it was fixing a problem that there was no evidence existed.

Again, one has to be careful in making sure conclusions are drawn from the correct areas. The OE fan does restrict flow, however, it is necessary and, when operating, increases airflow far more than it restricts it. A second fan would only be needed if the OE-fan did not have the capacity to remove sufficient thermal-load from the rad, or if the OE-fan had shown any suggestion of being suseptible to failure. AFAIK, neither of these two criteria exist, so a second fan is of no practical benefit.

All the laser does is give you placement so that it is repeatable. It doesn't change the fact that what is being used to measure the differences is not capable of doing so from outside the system in the manner you described. As simple example is that many after-market oil temperature sensors placed inside the engine are quite worthless because they are placed in the wrong spot internally and therefore cannot measure what needs to be measured due to the cooling and merging effects of the system. Using something outside the system is even less meaningful and an infared pyrometer (laser or not) will tell very little if anything, so I'm not surprised that there was little or no difference in the readings. I would not expect there to be under those conditions.

Like you say, to each their own. I do things that some think aren't necessary and I don't do things that some swear must be done. Ride safe.


I appreciate all the chatter and options expressed on what I did by my additional fan install. Look it's just me thinking I wated a backup, simple, not a huge deal. If you think otherwise fine, however my bike my deal. I've owned 3 RT's now and I still have my wonderful 1995 k75 ABS. I have always done all my own work on all my bikes from my benelli 50 on up to this RT. I purchased the waterproof switch from twister t and isolated the circut fir before said reason. Ride your own ride and I guess that can be said for other stuff as well. I simply wated to take my time and show you how it's done IF ANYONE CARES.
Enjoy your ride gets and ladies 🏍😀
 
I appreciate all the chatter and options expressed on what I did by my additional fan install. I simply wated to take my time and show you how it's done IF ANYONE CARES.
Enjoy your ride gents and ladies 🏍😀
I'm originally from TN. I appreciate you sticking the ole neck out! Hooray for sharing.
 
Losing your rad fan simply means you would have to avoid extended preiods of riding below 20-30~ mph.

I had an '86 K75C that I bought used. I rode it for years before one day I found out the radiator fan didn't work. I had got caught in a big-city traffic jam. The small town I live in never has a traffic jam, and within 5 minutes you are out in the country.

The day the bike overheated, and I realized the radiator fan did not work, I lane-split out of the traffic jam and rode home 70 miles without a problem.

I did replace that radiator fan.
 
Last edited:
Yes, most can manage without the existing fan. Doesn't mean they should be run that way, but it can be done.

I had a new vehicle about 20 years ago that I drove the entire length of the US and around Florida without any hint that they'd neglected to connect the wiring for its electric fan when it was being built at the factory, until it started to overheat while stuck for a prolonged period in construction. Drove it another 2,500 miles before connecting it with absolutely no issues.

On the other hand, I about 10 years prior to that I had another new car whose electric fan was needed if I spent too much time looking for a parking spot!!!

It is all a matter of design and thermal capacity.
 
...i appreciate all the chatter and options expressed on what i did by my additional fan install. Look it's just me thinking i wated a backup, simple, not a huge deal. If you think otherwise fine, however my bike my deal. I've owned 3 rt's now and i still have my wonderful 1995 k75 abs. I have always done all my own work on all my bikes from my benelli 50 on up to this rt. I purchased the waterproof switch from twister t and isolated the circut fir before said reason. Ride your own ride and i guess that can be said for other stuff as well. I simply wated to take my time and show you how it's done if anyone cares.
Enjoy your ride gets and ladies ����

It is your ..."bike, and your deal," and I really appreciate your bringing up the subject matter. The replies pro and con are also appreciated. Let's continue to keep it polite and curtious.

I would like to hear comments from a peace officer, if we have one on the site, who currently rides an authority R1200RTLC in heavy traffic. I got a 2018 R1200RT LC a month ago so I don't have much experience in this area. In fact, until you mentioned it a while ago and I looked at my bike, I did not even realize that I had only one fan on the bike. I did have an oil cooled '96 R1100R that I rode in heavy Houston traffic on almost a weekly basis with no over heating issues.


E.
 
On a side note on fans, we have KTM 390 and 690 Dukes. The 390 produced in India like the BMW 310.

The fan on the 690 only comes on in stop-n-go traffic, but the 390 comes on a lot and early in my mind.
The answer/thoughts on the KTM forum is the thermostat is set up for the hotter conditions in the producing country...and the early models had some fan failures.At least ours runs, but is annoying to hear it as much. All fins are clear, coolant fresh, just H and her right wrist brings it to life after a fast run.

My only concern with the dual fans is where is the heat going when sitting in traffic. The F800GT comes to mind as it will warm a leg in a bad way!
 
I did a bit of an acid test on my '16 RT when we road from Bishop CA to St George UT on June 5, 2016. This entailed over 4h at over 109F, and the last 2.3h of that was between 112F and 113F going uphill all the way! The coolant temp never went over the midpoint where it gets to when it's 28F outside. A hyperkewl jacket kept me from needing to pull over every 30m for water/hydration at that ridiculous temp. And what's more, tire pressure stayed virtually unchanged the entire trip after the requisite 2m tire warm up--and bonus, PR4GT's maximum tire temp rating was...113F and the tire did not, I repeat, did not start melting! I imagine w/ ambient temps of 112.9F the road surface in direct sun must be 160F+.

Now if you really want to insure that extra edge of cooling on your RTW, why not do what I did w/ my old Chrysler station wagon that was suffering from poor cooling for probably several reasons: I re-routed the windshield washer hose/sprayer ends and had them aimed dead at the front of the radiator. I would hit the windshield washer to spritz the radiator when going up hills in hot weather and yes, it worked! You are taking advantage of the massive calorie consumption it takes to convert liquid water into water vapor: it takes only 1 calorie to raise the temperature of 1 gm of water 1 degree Celsius, but it takes 580 calories to convert 1 gm of water into steam. If you were doing lots of stop n go driving it might be worth having something this--hijack the parts that could work from an old car and go from there. 1 gallon of water converted to steam takes 2,192,400 calories--which is enough to meet the caloric needs of over 1000 RTW riders for 24h!
 
I did a bit of an acid test on my '16 RT when we road from Bishop CA to St George UT on June 5, 2016. This entailed over 4h at over 109F, and the last 2.3h of that was between 112F and 113F going uphill all the way! The coolant temp never went over the midpoint where it gets to when it's 28F outside. A hyperkewl jacket kept me from needing to pull over every 30m for water/hydration at that ridiculous temp. And what's more, tire pressure stayed virtually unchanged the entire trip after the requisite 2m tire warm up--and bonus, PR4GT's maximum tire temp rating was...113F and the tire did not, I repeat, did not start melting! I imagine w/ ambient temps of 112.9F the road surface in direct sun must be 160F+.

Now if you really want to insure that extra edge of cooling on your RTW, why not do what I did w/ my old Chrysler station wagon that was suffering from poor cooling for probably several reasons: I re-routed the windshield washer hose/sprayer ends and had them aimed dead at the front of the radiator. I would hit the windshield washer to spritz the radiator when going up hills in hot weather and yes, it worked! You are taking advantage of the massive calorie consumption it takes to convert liquid water into water vapor: it takes only 1 calorie to raise the temperature of 1 gm of water 1 degree Celsius, but it takes 580 calories to convert 1 gm of water into steam. If you were doing lots of stop n go driving it might be worth having something this--hijack the parts that could work from an old car and go from there. 1 gallon of water converted to steam takes 2,192,400 calories--which is enough to meet the caloric needs of over 1000 RTW riders for 24h!

Wow that's some heat! Can you tell us your speed?

Jay
 
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