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I'm leaning towards the neutral switch first (in the first group of codes before clearing), bad connection or internal fault when hot sending a false reading, then TR sensor, then shift control motor overheating in stop and go traffic. If it was the shift pin or TR sensor I think I would be seeing problems in up/down and all gears.
The codes are being thrown at the time of the motor failure and may just be at what point the PCM is at in that moment. But the sound I heard when turning to "run" was the motor cycling, trying to find neutral (I assume). The problem with trying to figure it out in my head is not knowing the initialization logic. Need to test until complete failure to properly troubleshoot intermittent/heat related troubles.
 

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Do you think the issue lies within the reduction gears itself or just the shift control motor? I think just swapping out the shift control motor might be the easiest thing to try first. I don't think you have to pull out the reduction gears if you're just swapping out the motor, at least not on the nc700xd. That's what I'm going to try. But I do acknowledge that I may potentially be paying over $200 for a part that might not even solve the issue.

I just don't really know what to do at this point since the DTC codes are not helping and they tested my shift motor and it ran fine in both directions. But the issue is it needs to be tested under heavy and hard load when it's very hot. The service tech also idled my bike and rode it around for several minutes and was unable to replicate the issue. This is such a pain in the ass.
I'm not so sure we are having a mechanical related failure. Something is getting hot in both our bikes. Since you are out of warranty, go through all your connections by reseating them. Pull them off, look at the wiring going into the back of the connector heads with a bright light, sometimes a bad crimp to a pin can get weak. Bad connections can cause high resistance opens, work when cool, open when hot.
 

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Got off the phone with service. They took apart the crankcase and checked everything related to the shift drum assembly and the dreaded "shift drum center bolt" aka the "shifter pin" that is known to come loose. Everything was perfectly fine and tightened. Everything looked clean and there was no visible wear or damage. So that is ruled out. The DTC codes that were stored were 24-1 and 57-1. 24-1 is related to the shift control motor drive circuit and 57-1 is "gear shift mechanism malfunction", and/or TR sensor malfunction. They tested the TR sensor so it wasn't that, and the shift motor tested fine as well but it wasn't tested under heavy load and high heat. The next step in accordance to Honda/service manual is to replace the ECU/PCM unit.

They also called Honda and Honda told them to check for that shifter pin and also check the shift control motor, which they already did but they're going to do it again. The Honda support tech told the service tech that the slightly low oil could have been a factor as well, though I am skeptical.

I already have an order for a replacement shift motor which I ordered from Partzilla with expedited shipping. So I'll be swapping that out first before I authorize them to replace the ECU.
 

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I'm not so sure we are having a mechanical related failure. Something is getting hot in both our bikes. Since you are out of warranty, go through all your connections by reseating them. Pull them off, look at the wiring going into the back of the connector heads with a bright light, sometimes a bad crimp to a pin can get weak. Bad connections can cause high resistance opens, work when cool, open when hot.
Yes I had them check the connections and sensors and they appeared to be in optimal condition. I am almost positive I am dealing with a faulty shift control motor that starts to malfunction when it gets too hot, which is why it wasn't able to be replicated when tested (per the service manual). I have one ordered but it's gonna be a week or so before it arrives.
 

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Either since I don't think they they have any moving parts.

The shift motor and loose shift drum bolt seem to be the majority of the failures of CTX and NC DCT models that I have seen posted.

The incidence of any kind of failure is pretty low, which is why there aren't many definitive "fixes" posted.

Disclaimer: I have about as much experience as the average Honda tech when it comes to DCT problems. I am just saying what "I" would do if I were in your situation.

I am still hopeful that some kind soul will do a video of how to check/repair the loose shift drum bolt issue someday.

Good luck to you.
Indeed. And it's not just the CTX and NC's, I've also been reading about the shift motor failing on Africa Twins, NM4's, Goldwings, and VFR1200's. But it makes sense since they all share the same part.

BTW I did find a video of someone pulling out the "shifter pin" (called Shift Drum center bolt on service manual) on an NC750 (unclear what year, and if X or S version). There's no audio with the video but it appears in this instance that it was loose.

 

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Yes I had them check the connections and sensors and they appeared to be in optimal condition. I am almost positive I am dealing with a faulty shift control motor that starts to malfunction when it gets too hot, which is why it wasn't able to be replicated when tested (per the service manual). I have one ordered but it's gonna be a week or so before it arrives.
I haven't seen any instance where replacing the ECU fixed this issue.
Indeed. And it's not just the CTX and NC's, I've also been reading about the shift motor failing on Africa Twins, NM4's, Goldwings, and VFR1200's. But it makes sense since they all share the same part.

BTW I did find a video of someone pulling out the "shifter pin" (called Shift Drum center bolt on service manual) on an NC750 (unclear what year, and if X or S version). There's no audio with the video but it appears in this instance that it was loose.

I have seen that video. It looks like the bolt is sheared. It also looks like he puts a new bolt back with no thread locker. A little narration would have gone a long way...Definitely not an intermittent issue.

I hope the new motor works for you. Be sure and let us know.
 

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I haven't seen any instance where replacing the ECU fixed this issue.


I have seen that video. It looks like the bolt is sheared. It also looks like he puts a new bolt back with no thread locker. A little narration would have gone a long way...Definitely not an intermittent issue.

I hope the new motor works for you. Be sure and let us know.
Yeah I really hope that's the case. Thank you!
 

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Indeed. And it's not just the CTX and NC's, I've also been reading about the shift motor failing on Africa Twins, NM4's, Goldwings, and VFR1200's. But it makes sense since they all share the same part.
BTW I did find a video of someone pulling out the "shifter pin" (called Shift Drum center bolt on service manual) on an NC750 (unclear what year, and if X or S version). There's no audio with the video but it appears in this instance that it was loose.

Thanks for posting the video!! On page 12-73 the service manual says to remove the gearshift linkage to access the center bolt you should remove the shift control/reduction gears and dual clutch. It appears he was able to access the bolt by just removing the crankcase cover. I wouldn’t hesitate to check it myself in the future if necessary. The shift motor vie the reduction gears must be able to exert a tremendous amount of force to snap the bolt off.
Hope the shift motor solves your problem. The PGM FI unit goes for $628.60 on Revzilla if I have the right part #; Partszilla sells it for $778.90. I am finding Revzilla to have better pricing, free shipping over $39.99, Zilla cash back and compares favorably against Partszilla.
Honda 38770-MKA-G52 PGM-FI UNIT - RevZilla
 

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Great video of the shift bolt. The bolt had the pin head sheared off of the nut head.
I think the manual test procedure is insufficient to properly test for heat failure, it seems more a go/no go test. The only way to really test the shift control motor is to pull it and run a bench test on it until it gets hot. That would entail using a battery as per the test procedure but one would have to try to mimic the polarity change constantly. I wouldn't recommend running it too long in one direction, not sure if it's meant for a long duty cycle. And not being under load may not be enough either.
Letting my dealer work this out under warranty, I imagine they will swap the shift motor and run their road test again. That's what I would do.
Since my failure is repeatable, they may just have to take SWAG's ( scientific wild ass guesses ). I think I would be also if it wasn't under an extended warranty
I won't be getting it back anytime soon though, they are busy like crazy this year with all the people escaping from New York. But I'm okay with that, I can ride all year. As long as it's fixed. Will post follow ups.
 

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I have not had any problems with DCT so far, but I drive very sporadically and almost not at all in the last 12 months. But from my observations, in the 9 or so years of owning DCT, my confidence in Honda's quality and design is quite shaken.
The Shift Control Motor on this DCT has no reason to be hot.
By design, there are no factors to cause overheating. Gear shifting occurs without load. You can only hear the mechanical impact. In principle, the gearshift mechanism does not differ much from the standard gearbox. Shift Control Motor makes an almost insignificant number of revolutions. There is no data for this, but I do not suppose that a gear change would require more than 2-3 turns of the Shift Control Motor. Even driving in heavy city traffic or a lot of traffic lights will not give you a reason to overheat. But if the Shift Motor does break down anyway, that means Honda has a problem with trusted component suppliers.
 

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Sorry to hear of your problems. The oil claim tells you they are not interested in you or your problem. Honda warranty probably wont pay due to they cannot reproduce the problem so its not broke. This is where a camera could document the issue as proof of warranty claim. You could use your cell phone when it happens again. Telecam on the NC 700 forum had a similar problem and is worth a read. I think in the end after a lot of grief and needless parts replacements they compared the shift motor to one off another bike and found that it was weak by comparison and a new shift motor cured the problem. Not saying this is your problem!!! On the video I think holding the brake while manipulating the shift buttons is the key to getting it back to neutral.

Notice when he first turns the key off then back on you can here a repetitive whine and click. I believe this is the shift motor trying and failing to reset the transmission back to the neutral position. Possibly after he gets the bike started and the motor spinning and clutch engaged with the brake on, it loosens up the gear box and allows the shift motor to do its job. When you get the flashing – it should store a DTC in the computer. Good luck!!

Dct Troubleshooting Information; Dct System Description - Honda CTX700N/ND Service Manual [Page 247] | ManualsLib
Almost sounds like the shift motor is beginning to fail and overheating. Although this the following is for an honda ATV shift motor, the problem sounds the same.
"I have a 2008 Honda Rancher 420 ES. A few years ago I had a problem with it not shifting or sounding sluggish when trying to shift. As well, the display would often flash a bar or flash the gear the machine was stuck in.

After checking the net and finding no real answer to the situation, I read that the problem may be a 'shift angle sensor' or 'bank angle sensor'. After purchasing a new shift angle sensor @$100. as well as cleaning the shift motor, the problem soon came back....today, two years later."

Also there has been problems with the "grease" used in the shift motor becoming sticky in some environments.
 

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I have not had any problems with DCT so far, but I drive very sporadically and almost not at all in the last 12 months. But from my observations, in the 9 or so years of owning DCT, my confidence in Honda's quality and design is quite shaken.
The Shift Control Motor on this DCT has no reason to be hot.
By design, there are no factors to cause overheating. Gear shifting occurs without load. You can only hear the mechanical impact. In principle, the gearshift mechanism does not differ much from the standard gearbox. Shift Control Motor makes an almost insignificant number of revolutions. There is no data for this, but I do not suppose that a gear change would require more than 2-3 turns of the Shift Control Motor. Even driving in heavy city traffic or a lot of traffic lights will not give you a reason to overheat. But if the Shift Motor does break down anyway, that means Honda has a problem with trusted component suppliers.
Direct heat or contact heat transfer could cause the shift motor to overheat. Also if there is resistance to shifting by the grease used in the motor having thickened could cause overheating.
 

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Direct heat or contact heat transfer could cause the shift motor to overheat. Also if there is resistance to shifting by the grease used in the motor having thickened could cause overheating.
First, what internal temperature in this electric shift control motor is considered by the designers to be overheating? DCT, in conjunction with the motorcycle's engine is a liquid-cooled, i.e. internal temperatures in the DCT do not exceed approximately 98 degrees Celsius. The shift motor housing is made of aluminum alloy (very good heat conductor) and is attached to a reduction gear cover also made of aluminum alloy. So the conduction heat is distributed and cooled fairly quickly. On the outside, this shift motor is air-cooled, which even in Arizona does not often exceed 40 degrees Celsius. And while riding, there is a cooling effect of a moving motorcycle.
And the second thing. Who packs the grease inside the electric motor? A ball bearings with a sealed lubricant is probably used - statistically indestructible given the minimal movement of the motor's shaft.
 

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First, what internal temperature in this electric shift control motor is considered by the designers to be overheating? DCT, in conjunction with the motorcycle's engine is a liquid-cooled, i.e. internal temperatures in the DCT do not exceed approximately 98 degrees Celsius. The shift motor housing is made of aluminum alloy (very good heat conductor) and is attached to a reduction gear cover also made of aluminum alloy. So the conduction heat is distributed and cooled fairly quickly. On the outside, this shift motor is air-cooled, which even in Arizona does not often exceed 40 degrees Celsius. And while riding, there is a cooling effect of a moving motorcycle.
And the second thing. Who packs the grease inside the electric motor? A ball bearings with a sealed lubricant is probably used - statistically indestructible given the minimal movement of the motor's shaft.
Could it potentially be dried up grease from the reduction gears that makes its way to the shift motor's shaft that could cause any trouble? The reason I ask is because when I pulled out my shift motor to inspect it I saw some white crud/residue that was stuck to the shift motor's shaft. Then I saw on the service manual that the reduction gears requires 2-4 grams of "Unirex N3 grease (Exxon Mobil)" on the journals and teeth, which the shift motor's shaft rests against.
 

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I think there may be a winding failure within the motor. This can cause intermittent problems as the insulation of a winding breaks down and causes a short or open within the motor. It can also cause a high resistance open ( also known as a series resistance). A high open can be tested when the resistance across a wire is known and the device measures a higher resistance. You can use a "breakdown" box to push a higher voltage than normal voltage across the wire, it will go open when stressed. A short in the windings can be measured/tested the same way. But if it's heat related it becomes more difficult.

I used to work for AT&T as a facilities technician. High opens are a nightmare to troubleshoot since there can be several splice locations in a cable. We used a Longitudinal Balance test to measure the wire pairs ability to shunt out unwanted AC. The twists in phone wires accomplish that. If there is an open, the ability to shunt unwanted AC is diminished . If the balance was less than 60db it indicated a problem. Once a high open was indicated, we shorted the wire pair at one end to each other and to ground and tested the short and each side to ground to find which of the 2 wires measured a higher resistance. Each wire to ground should measure half the total resistance of the short, even a 5 ohm difference would cause a problem. The higher resistance side was the bad one.
Breakdown boxes were not allowed to be used because much telephone wire is 26 gauge and you would burn it before breaking the open. Our standard "opens" test could not be used to find high opens since it only measured wire length, a high open will show continuity until it fails. The use of a Time Domain Reflectometer would tell us where the open was and show a bad reflection waveform of a high open. Much of our cable was above ground in the hot Florida sun, customers with high opens would report problems later in the day as the cables heated up. Causes were bad/corroded splices, or nicks caused by squirrels or tree damage into the cable.

Can't do all that with a small motor so I would just shotgun the motor and test ride to replicate failure. The sensors are probably piezo transducers and they can go bad but really hard to test for heat.
 

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Could it potentially be dried up grease from the reduction gears that makes its way to the shift motor's shaft that could cause any trouble? The reason I ask is because when I pulled out my shift motor to inspect it I saw some white crud/residue that was stuck to the shift motor's shaft. Then I saw on the service manual that the reduction gears requires 2-4 grams of "Unirex N3 grease (Exxon Mobil)" on the journals and teeth, which the shift motor's shaft rests against.
You ask about the basics of mechanical devices. This electric motor is sealed, i.e. a wheel seal or a grease seal or whatever is called in use today. Proven and highly effective for sealing rotating parts.
It's good that you mentioned the grease recommended by Honda for use on reduction gear journals and teeth. This is "lithium-complex products suitable for high-temperature service". And the recommended amount is 2 - 4 g. This is about as much as you put toothpaste on a toothbrush - a very minimal amount. It practically does not dry out and is effective at temperatures well over 212 F.
 

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First, what internal temperature in this electric shift control motor is considered by the designers to be overheating? DCT, in conjunction with the motorcycle's engine is a liquid-cooled, i.e. internal temperatures in the DCT do not exceed approximately 98 degrees Celsius. The shift motor housing is made of aluminum alloy (very good heat conductor) and is attached to a reduction gear cover also made of aluminum alloy. So the conduction heat is distributed and cooled fairly quickly. On the outside, this shift motor is air-cooled, which even in Arizona does not often exceed 40 degrees Celsius. And while riding, there is a cooling effect of a moving motorcycle.
And the second thing. Who packs the grease inside the electric motor? A ball bearings with a sealed lubricant is probably used - statistically indestructible given the minimal movement of the motor's shaft.
Just assuming that Honda may use the same procedures on the MCs as they do on the ATVs. Since the exact same problem has been noted on ATVs and a solution found.
 

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Just assuming that Honda may use the same procedures on the MCs as they do on the ATVs. Since the exact same problem has been noted on ATVs and a solution found.
What I want to say, I doubt that overheating or dried grease would be the cause of this electric motor breaking down. Poor production quality can be a factor. Choosing a supplier for price, not quality. This DC electric motor is not much different from the one commonly used in cordless power drills, which are often used in quite harsh environments and perform well. I think Honda wants to save too much.
 

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What I want to say, I doubt that overheating or dried grease would be the cause of this electric motor breaking down. Poor production quality can be a factor. Choosing a supplier for price, not quality. This DC electric motor is not much different from the one commonly used in cordless power drills, which are often used in quite harsh environments and perform well. I think Honda wants to save too much.
You may be right, although I have had power drills fail as well. Too bad we cannot find out production lots. This problem seems to be fairly new in the CTX but somewhat common on the ATV apparently.
 

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Got off the phone with service. They took apart the crankcase and checked everything related to the shift drum assembly and the dreaded "shift drum center bolt" aka the "shifter pin" that is known to come loose. Everything was perfectly fine and tightened. Everything looked clean and there was no visible wear or damage. So that is ruled out. The DTC codes that were stored were 24-1 and 57-1. 24-1 is related to the shift control motor drive circuit and 57-1 is "gear shift mechanism malfunction", and/or TR sensor malfunction. They tested the TR sensor so it wasn't that, and the shift motor tested fine as well but it wasn't tested under heavy load and high heat. The next step in accordance to Honda/service manual is to replace the ECU/PCM unit.

They also called Honda and Honda told them to check for that shifter pin and also check the shift control motor, which they already did but they're going to do it again. The Honda support tech told the service tech that the slightly low oil could have been a factor as well, though I am skeptical.

I already have an order for a replacement shift motor which I ordered from Partzilla with expedited shipping. So I'll be swapping that out first before I authorize them to replace the ECU.
Here is a report on Shifter problem in the NC700. I believe the same parts are used. "
On 9/14/19 I related a DCT problem on my 2016 NC700XD with 36,000 miles. It was stuck in 2nd gear and wouldn’t start. I finally got it back in neutral and functioning normally after lots of fiddling but my concern at that time was that I didn’t know for sure what had caused the problem and how to avoid it in the future.

On 12/26/19 at 38,500 miles it happened again with me limping home in who knows what gear (none displayed) and once again finally getting it back in what looked like normal function again. The next day I took another ride and everything worked fine until I stopped after about a one hour ride. Upon restarting and riding ~100’ gear position showed no gear but “-“ fast blinking. Thinking I could fix that using the same procedures as before I stopped and turned it off. Bad decision. It wouldn’t do anything at all. Called my roadside assistance and was towed to the Honda dealer.

Since this dealer has zero experience with the NC700XD they called Honda Tech and were told that they are seeing high mileage bikes with a loose Star Bolt causing similar problems (as mentioned in other posts). They were told to remove and replace the bolt after applying locktite. My shop manual says it’s supposed to be locktited but for some reason Honda didn’t do that on some or all, I don’t know which. Mine was not loose and did not have locktite on it, but it does now. So that wasn’t the problem. While in there, I asked them to check the clutch pack for wear and they reported all looked very good.

Dealer was then told by Honda to replace the shift motor which they did. They buttoned it up and it still displayed D+S but it functioned like normal and I could switch between D & S so I went through the calibration process with the side stand up and starting while holding the brake to finally get it back to normal function. I’ve now ridden it about 350 miles and hope the problem is solved since I’ve had no malfunctions.

Feedback from the Honda Dealer was that the shift motor had an open short. They said the motor over heats causing the motor to fail. Why the motor overheated was not explained. Often I do ride in D using frequent downshifts with the paddle shifter while exiting a curve or going up an incline. Other times I’ll be in S2 and let it do all the shifting, but I don’t think I do anything to overtax the shift motor.

So, I do admit to having my confidence in the DCT shaken but it does seem to be fixed and I hope to ride many more miles on this bike. I’m now 79 and really like the ability of not having to use a clutch/foot shift and I particularly like the different modes to change the character of the bike.
 
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