FCS Thermal Creep Switch Issues
I've had the snap switch installed for about a week. It comes on at just under 240 when the bike is sitting still and switches off at 200 +or - 5 degrees. The ambient temps were between 45 & 70 during this time. I may try reinstalling the switch so it contacts the head wall instead of on the cooling fin.
Thread Starter
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Banned
Joined: Apr 2012
Posts: 648
Likes: 9
From: WV
I've got very little experience with these switches so far, other then ensuring they would function properly for the application. I've only shipped about 15 with feedback from 4. Unfortunately I had to leave the shop right after I got the batch I ordered, so no opportunity to play with them or create new install instructions. I personally have only tried two different calibrations on my bike, that both worked well. I did notice they seem to be more sensitive to install position and the amount of RTV used. I'll be back in the shop tomorrow, and soon as I catch up on fans I'll get back to work on the switches. I also noticed the snap switch operation temps fluctuate a little more than the creep. I've got some Ideas to improve the install that should also improve predictability of operation. Give me a little time to receive feedback and conduct my own experiments and I'll publish switch info as it develops. All the positive attributes of this new switch are encouraging, I just have to refine the install.
Advanced
Joined: Aug 2011
Posts: 63
Likes: 2
From: Pittsburgh
I too have new switch. Install was easy. Took small artist brush and dipped into RTV in tube. Painted switch bottom and back that goes up against head. Little extra dab or two for good measure. Not overloaded though.
Used switch wires to position switch in fin without touching until I got in spot I wanted which was all the way up against head. Then used chop stick (use them for mixing epoxies) to push switch down on fin and then back to head.
Didn't move when I pushed as I had it in right spot but the intent was to mate RTV to fin/head. Folded cardboard envelope switch came in to press in place overnight. Wedged it between switch and fin above. Pushed one last time to ensure it was tight against head but really didn't need that last push. Let dry for 24 hours per RTV instructions.
Old switch seemed to cycle on and off after shut off. Eventually it kept running longer and longer cycles until it didn't stop. New switch doesn't cycle. Just runs after shutdown and stops with no cycling.
Got stuck in hour and a half traffic jam due to wreck. Got off parkway but so did every body else. Rode 5 to 15 MPH whole time in 80 plus degrees. Bike without fan would have been pinging. No pinging with fan.
Got home and bike was hottest it ever was since I bought it in April. Fan ran a long time. I sat and watched it. Shut off once and that was it.
4 days later I was in mountains and woke up to 34 degrees with frost on bike. Coasted down 4 mile mountain. Fan stayed off. Going up other side two up fan came on and stayed on. Ok with me as it seems that once the motor heats up it stays that way. Even in colder temps.
Switched off quick though when I stopped to see truck that didn't make safety gravel and embedded itself into trees. Cops said driver ok but I bet that was a ride. It was way up the mountain side. I could still smell brakes and I came hours later. That's something you don't want to see coming at you in mirror.
The new switch just seems to be more stable during operation. I don't have a tool to read head temps but I can almost tell now when this one will come on and I can estimate how long it will run after shutdown based on heat being thrown off bike. Need to get rid of the cat soon.
This switch and fan combo is working great for me.
Used switch wires to position switch in fin without touching until I got in spot I wanted which was all the way up against head. Then used chop stick (use them for mixing epoxies) to push switch down on fin and then back to head.
Didn't move when I pushed as I had it in right spot but the intent was to mate RTV to fin/head. Folded cardboard envelope switch came in to press in place overnight. Wedged it between switch and fin above. Pushed one last time to ensure it was tight against head but really didn't need that last push. Let dry for 24 hours per RTV instructions.
Old switch seemed to cycle on and off after shut off. Eventually it kept running longer and longer cycles until it didn't stop. New switch doesn't cycle. Just runs after shutdown and stops with no cycling.
Got stuck in hour and a half traffic jam due to wreck. Got off parkway but so did every body else. Rode 5 to 15 MPH whole time in 80 plus degrees. Bike without fan would have been pinging. No pinging with fan.
Got home and bike was hottest it ever was since I bought it in April. Fan ran a long time. I sat and watched it. Shut off once and that was it.
4 days later I was in mountains and woke up to 34 degrees with frost on bike. Coasted down 4 mile mountain. Fan stayed off. Going up other side two up fan came on and stayed on. Ok with me as it seems that once the motor heats up it stays that way. Even in colder temps.
Switched off quick though when I stopped to see truck that didn't make safety gravel and embedded itself into trees. Cops said driver ok but I bet that was a ride. It was way up the mountain side. I could still smell brakes and I came hours later. That's something you don't want to see coming at you in mirror.
The new switch just seems to be more stable during operation. I don't have a tool to read head temps but I can almost tell now when this one will come on and I can estimate how long it will run after shutdown based on heat being thrown off bike. Need to get rid of the cat soon.
This switch and fan combo is working great for me.
Thread Starter
|
Banned
Joined: Apr 2012
Posts: 648
Likes: 9
From: WV
Sorry about that, I'll admit I need to do some site maintenance, +$20.00 for the switch.
Tourer
Joined: Mar 2009
Posts: 413
Likes: 16
From: Killeen, Tx
I've had the snap switch installed for about a week. It comes on at just under 240 when the bike is sitting still and switches off at 200 +or - 5 degrees. The ambient temps were between 45 & 70 during this time. I may try reinstalling the switch so it contacts the head wall instead of on the cooling fin.
Ambient temp 74
Fans come on at 235 and shut off around 208-210
This is at idle in the garage.
Road Warrior
Joined: May 2009
Posts: 1,537
Likes: 4
From: The Great River Road, Wisconsin
Ride My Seesaws bypass cap fix sounds perfectly legit, if indeed it is a spike that is causing the welding. I didn't read all of the threads but this would resolve the arc.
Road Warrior
Joined: Dec 2012
Posts: 1,335
Likes: 5
From: CT
Just installed Snap switch yesterday. Let the high temp rtv set up and started tonight. Neighbor wasn't happy with bike running. Could hear him bitching across the street. Wouldn't come over and tell me he had a problem with noise. 7:45 in the evening so f'em.
Switch cut on around 235 and went off 190 or so. Looks good so far.
Switch cut on around 235 and went off 190 or so. Looks good so far.
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Seasoned HDF Member
Joined: Apr 2013
Posts: 32,851
Likes: 17,888
From: Newcastle, OK
So the down and dirty is I don't have an answer for why some folks have experienced problems with the creep switch. Most users have no problems withit, some have tens of thousands of trouble free miles, and some have craped out within a few days. I thought I was onto something with the member who swapped out his voltage regulator, but his replacement switch has malfunctioned also. I cant explain it because it is beyond my scope of understanding, and Im not tryingto feed anyone BS about it. Up to this point I have responded with the info supplied to me by the MFRs engineers based on their analysis of a good sampling of failed switches from customers. They suggest the erosion and transfer of contact material is evidence of a charging system issue, but it is lacking any in-depthexplanation of the condition, so Im moving forward looking for a different switch that will not exhibit this problem.
Im currently testing some new switches but their function is different. One customer already declined to try it because its functional characteristics are different from the original creep switch; he was accustomed to the fans coming on at 190F with the creep and didnt want the fans switching on at 250F with the snap, he just felt it was too high. I would like some more feedback from users; Im concerned there may be a potential psychological barrier since I have already established the normal operation with the creep switch, so anything new and different may seem wrong. The creep switch is a slow action device with a narrow on/off differential, it turns the fans on and off at about 190F, which really is a good calibration temp to maximize cooling potential. For the benefit of those not familiar with this subject, the creep switch does not maintain a head temp of 190F, that is simply where it comes on, then the fan system slows the climb to the stabilized temp, depending upon conditions. The snap action switches I am testing have a wide reset differential between on and off temperature, which raises some new considerations; the fans come on at about 250F,which is still acceptable in my opinion because that is just a little higher than the average where most bikes normalize with the fans running, under moderate operating conditions. With this new switch on my bike, the fans come on at 250F and then drop back down to about 235F, then depending on duration and intensity of the ride, the temp may hover at 235F or slowly creep back up to 250F. The fans go off at about 160F, which is lower than the creep switch, so the fans run a little longer during post operation cool down, but they dontcycle on and off as the engine heat sinks. Because of the wider differential, I had to compromise with the on/off temperature, I could go with a lower calibration and have them turn on at say 190F, similar to the creep switch, but the off temp would be like 100F so the fans would run much longer, or even continuous in hot climates. I could go with a higher calibration so the off temp would be 190F, similar to the creep switch, but they wouldnt come on until about 280F. The functional characteristics of the snap type switch may prevent ideal operation temperatures, but it should provide a much more durableand reliable automatic switch solution for this application.
Another observation was short trip operation, if I just ride a few miles or minutes, about 5 or less, the fans may not come on and the CHT can be almost 250F at shutdown, this probably wont happen too often so Im not sure its a major concern but, it warrants mention.
The positive attributes of this new switch are, sealed construction, housing is nonconductive so no more Mylar sheath to deal with like the creep switch, much higher amperage rating, it is also smaller at about ˝ the size of the current creep switch. The downside, the install is a little more involved and cant be rushed, overnight cure for the RTV is absolutely necessary, no more stuffit in there and go. Also the snap switch has light colored wires; once installed it is hidden behind the fans and not really visible unless you arelooking for it, but they can be covered with a black sheath so not a big deal.Custom configuration with black wires/housing and/or a narrower reset differential requires a 10,000 pc order so that probably isnt happening, Ill go with a standard configuration.
Mounting a different type of switch is the major stumbling block, there are all kinds of thermal switches available, but mounting them to the cylinder head is another thing. Robust thread-in type surface mount switches are available, but they require a threaded hole in the head, which most people will not be able or willing to drill and tap their head to add a thermal switch. I want to stay with a simple thermo-mechanical contact type switch on the cylinder head for a couple reasons; simplicity and function, when you move the switch to the rocker cover, or any other lateral component, too much heat and transfer time is lost when the probe is not placed directly on the head; the result is inconsistent on/off temps.
As mentioned numerous times in the past, I will stay on it until I find a simple solution; Im not going to add diodes, capacitors or any other components to create a sub-system and force this to work. If I cant find a suitable trouble free switch for this simple application, I will default back to manual operation just like before I offered a thermal switch. Feedback is welcome; Im trying to establish if folks will be receptive to the characteristics of this new switch. I did purchase a small batch to start sending out as a replacement for failed creep switches, they should be in by early Oct. They are calibratedabout 10F lower than the samples I got, so they should bring the on temperature down to about 240F and the off temp to about 150F, I believe this is about the best compromise within the functional limits of the switch. I think the automatic function alone is more important than the actual temperature values of the on and off functions. Removing the human error of forgetting to turn them on, or waiting too long to turn them on is what really helps to maximize the performance of the system. Regardless of what type or temperature calibration, with a thermal switch in the system, as soon as the engine warms up, the fans come on every time, no waiting to be reminded by the EITMS thump to turn them on.
Thanks all
Jason
Im currently testing some new switches but their function is different. One customer already declined to try it because its functional characteristics are different from the original creep switch; he was accustomed to the fans coming on at 190F with the creep and didnt want the fans switching on at 250F with the snap, he just felt it was too high. I would like some more feedback from users; Im concerned there may be a potential psychological barrier since I have already established the normal operation with the creep switch, so anything new and different may seem wrong. The creep switch is a slow action device with a narrow on/off differential, it turns the fans on and off at about 190F, which really is a good calibration temp to maximize cooling potential. For the benefit of those not familiar with this subject, the creep switch does not maintain a head temp of 190F, that is simply where it comes on, then the fan system slows the climb to the stabilized temp, depending upon conditions. The snap action switches I am testing have a wide reset differential between on and off temperature, which raises some new considerations; the fans come on at about 250F,which is still acceptable in my opinion because that is just a little higher than the average where most bikes normalize with the fans running, under moderate operating conditions. With this new switch on my bike, the fans come on at 250F and then drop back down to about 235F, then depending on duration and intensity of the ride, the temp may hover at 235F or slowly creep back up to 250F. The fans go off at about 160F, which is lower than the creep switch, so the fans run a little longer during post operation cool down, but they dontcycle on and off as the engine heat sinks. Because of the wider differential, I had to compromise with the on/off temperature, I could go with a lower calibration and have them turn on at say 190F, similar to the creep switch, but the off temp would be like 100F so the fans would run much longer, or even continuous in hot climates. I could go with a higher calibration so the off temp would be 190F, similar to the creep switch, but they wouldnt come on until about 280F. The functional characteristics of the snap type switch may prevent ideal operation temperatures, but it should provide a much more durableand reliable automatic switch solution for this application.
Another observation was short trip operation, if I just ride a few miles or minutes, about 5 or less, the fans may not come on and the CHT can be almost 250F at shutdown, this probably wont happen too often so Im not sure its a major concern but, it warrants mention.
The positive attributes of this new switch are, sealed construction, housing is nonconductive so no more Mylar sheath to deal with like the creep switch, much higher amperage rating, it is also smaller at about ˝ the size of the current creep switch. The downside, the install is a little more involved and cant be rushed, overnight cure for the RTV is absolutely necessary, no more stuffit in there and go. Also the snap switch has light colored wires; once installed it is hidden behind the fans and not really visible unless you arelooking for it, but they can be covered with a black sheath so not a big deal.Custom configuration with black wires/housing and/or a narrower reset differential requires a 10,000 pc order so that probably isnt happening, Ill go with a standard configuration.
Mounting a different type of switch is the major stumbling block, there are all kinds of thermal switches available, but mounting them to the cylinder head is another thing. Robust thread-in type surface mount switches are available, but they require a threaded hole in the head, which most people will not be able or willing to drill and tap their head to add a thermal switch. I want to stay with a simple thermo-mechanical contact type switch on the cylinder head for a couple reasons; simplicity and function, when you move the switch to the rocker cover, or any other lateral component, too much heat and transfer time is lost when the probe is not placed directly on the head; the result is inconsistent on/off temps.
As mentioned numerous times in the past, I will stay on it until I find a simple solution; Im not going to add diodes, capacitors or any other components to create a sub-system and force this to work. If I cant find a suitable trouble free switch for this simple application, I will default back to manual operation just like before I offered a thermal switch. Feedback is welcome; Im trying to establish if folks will be receptive to the characteristics of this new switch. I did purchase a small batch to start sending out as a replacement for failed creep switches, they should be in by early Oct. They are calibratedabout 10F lower than the samples I got, so they should bring the on temperature down to about 240F and the off temp to about 150F, I believe this is about the best compromise within the functional limits of the switch. I think the automatic function alone is more important than the actual temperature values of the on and off functions. Removing the human error of forgetting to turn them on, or waiting too long to turn them on is what really helps to maximize the performance of the system. Regardless of what type or temperature calibration, with a thermal switch in the system, as soon as the engine warms up, the fans come on every time, no waiting to be reminded by the EITMS thump to turn them on.
Thanks all
Jason
I`m retired from the HVAC industry, and the snap action switches I`ve been around have as little as 20* differential for start/stop. Most are 30* to 60* differential, with the "high limit" type for heaters shutting off in a hundred degree range from 300* degrees and lower. Are you sure you tried the companies that make these? (FASCO, ICP, MARS, etc.)