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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.
Ah ok then, I wasn't sure what that white crud was that was stuck to the shaft of the motor. It had the consistency of dried up glue and was crumbly.
 

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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.
Yeah I was actually able to talk to the guy who made that post (goes by Helix on NC700 forums). His post was one of the reasons why I immediately thought my shift motor might be going bad after it heats up. His bike was doing the exact same thing that mine does.
 

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Ah ok then, I wasn't sure what that white crud was that was stuck to the shaft of the motor. It had the consistency of dried up glue and was crumbly.
This could be Honda assembly markings on parts and components. I think I saw it in different places on the motorcycle.
 

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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.
I didn't know Honda used a shift control motor to shift the gears of their ATVs. The Honda Electric Shift Program (ESP) was used before DCT was used.
I found a Honda Rancher service manual and I see a major difference in the shift control motor operation between ESP program and DCT. In DCT, the shift motor only operates the shift drum with a very light load when shifting gears. In ATVs Electric Shifting, the shift motor operates the shift drum and the clutch, therefore the load for the shift motor is much larger and the possibility of overheating is increased. The possibility of overheating of the shift motor in the DCT is greatly minimized.

88064
 

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Thank you, that answered a question I had regarding the torque load on the DCT shift motor.
Will post the fix when finally done.
 

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So in theory the shift motor on a DCT should not really be getting any hotter than 'warm to the touch' right? If mine fails again I'll pop off the front sprocket cover and see how hot it is.
 

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So in theory the shift motor on a DCT should not really be getting any hotter than 'warm to the touch' right? If mine fails again I'll pop off the front sprocket cover and see how hot it is.
Don't do this. If you have, only use an IR thermometer to measure the temperature of the surface.
At this point, I honestly don't know how much you know how these things work.
The surface temperature of this shift motor may be 125 - 180 F (50 - 80 C) which does not mean the motor is overheated. For the most part it is temperature transmitted by thermal conduction and radiation. Of course, the electric motor also generates heat during operation, but in this case it is an incomparably smaller amount compared to the heat generated by the work of a motorcycle engine and gearbox.
 

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Ares301 is right, please don't touch hot surfaces. Surface temps are not a good indication of internal temps anyway due to the heatsink effect of an objects case and mounting.
Heard from the dealer today, replacing shift control motor. Got it to fail when load testing. Not sure what they mean by "load" testing but they were able to get it to fail in 10 mins. They probable noticed it it stuttering or failing to reverse immediately as it was heating up.
Thats a bad winding, not initially caused by heat but bad coating of the windings ( shorting) or the high resistance open I had mentioned earlier failing when hot. Both are manufacturing defects. The wire gauge for winding is tiny, almost hairlike.
When the bike is just cruising around in S mode, there is not very much action on the motor. That said I probably would have seen it worse in D mode as the shift points come quicker. My issue was in stop and go traffic, that would make the motor work more often hence just a bit hotter going between 2nd and 1st, back to 2nd so much.

It was covered under my extended warranty ($750). If not the total bill was about $580. So figuring the tow at $150 ( covered) and the bill, I paid it forward 5 years ago. I really expected them to take longer to get around to fully testing for repair. So now waiting on part.
 

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Yeah don't worry I'm not gonna touch it and burn my hand lol. I was thinking more along the lines of spraying it with a spray bottle and see if the motor is scathing hot to the point where it evaporates the water instantly.

But yeah my new shift motor arrived today and I just finished installing it so I'm about to go for a ride and see how it goes.
 

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... My issue was in stop and go traffic, that would make the motor work more often hence just a bit hotter going between 2nd and 1st, back to 2nd so much.
Do you realize that DCT does not shift from 1st to 2nd gear and back to 1st. So in this gear range the shift motor is not involved at all, i.e. it is turned off. The gear change in this range is done only by clutches No.1 and No.2. Only if you start accelerating in 2nd gear, the PCM signals to shift from 1st to 3rd gear. If you start to slow down in 2nd gear, it changes from 3rd to 1st gear, if there is already a gear change. So in the range of a few hundred feet, the shift motor will make a few turns in one direction and maybe a few turns in the opposite direction. So where can you find the reason for overheating of this motor?
I can only give one possible fault with this shift motor. If it is a brush motor, I see the possibility of brush wear to such an extent that there is occasional loss of good contact with the commutator and the motor refuses to change the direction of rotation. It is quite difficult to check it in tests.
 

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The new shift motor arrived today. I installed it and just came back from a roughly 2 hour ride putting 30 miles on the new motor. I made sure to do lots of stop and go traffic and tried to put as much strain on the shift motor as possible by staying in drive mode and doing hard braking when coming to a stop. It handled perfectly fine. Though, this doesn't exactly mean the problem is fixed since I was able to ride home with the old shift motor from the dealership on Tuesday without an issue. It will take a lot more testing to figure out if this solved the issue. I will be going for another ride tonight and see what happens.
 

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Here's my thread on the NC700 forums if anyone is interested in reading.
 

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I can only give one possible fault with this shift motor. If it is a brush motor, I see the possibility of brush wear to such an extent that there is occasional loss of good contact with the commutator and the motor refuses to change the direction of rotation. It is quite difficult to check it in tests.
I can confirm it's brushed motor. I opened mine up a while ago when I was first having this issue.

Another ride in the books with the new shift motor. 42 miles over the course of 2 hours. No signs of anything wrong. The DCT is shifting smooth as butter, but more testing will be needed.
 

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As I am not sure of exactly how the motor failed in bench testing, but a bad brush could be fault the also. I was focusing on the heat up issue since it occurred after riding a while, and didn't consider the brushes. I think if it was the brushes I would have seen the failure when changing through all the gears, up and down. Which brings me back to a question I posed earlier, although it may sound silly, are the reduction gears held in position by a constant voltage on the motor?

The advantage of a dc series motor is the high torque applied when activated. So whatever the fault, not enough umph, to move the reduction gears.
If I wasn't under a warranty, I would have replaced the motor myself and be done with it, since it's the most likely point of failure based on function. I don't think the codes help much on intermittent problems. It's not a difficult bike to work on if you don't have to drop the plastic shrouds. I had the dealer replace my air filter, but the brakes and battery I did myself. This motor replacement looked real easy too.
 

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...Which brings me back to a question I posed earlier, although it may sound silly, are the reduction gears held in position by a constant voltage on the motor?..
The reduction gears are held in position in exactly the same way as in a manual gearbox. The shift motor operates on the shift drum. What is done in the manual gearbox via the levers, in DCT the shift motor does.
 

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Just put another 62 miles on the new shift motor. The ride went flawlessly. This puts me at 134 miles in total w/ the new motor. Will wait until 250 miles until I can say with confidence that the issue has been fixed.
 

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Sounds great and thanks for keeping us up to date. I bought a used backup shift motor off EBay for $40.00 a few years ago. It is a Mitsuba AZ12. I checked their website but they don’t have any diagrams or data sheets on it for testing purposes. Attached are a couple pictures I have found of it disassembled. If you have a bad one, hold onto it. Worse case scenario if in the future when parts are scarce and you need one sometimes they can be rebuilt or reconditioned. Doesn’t look much different than a car starter that they reman all of the time. The issue could be as simple as a weak brush spring inside the motor or boogered up dirty commutator. Having a dirty commutator can cause a poor connection between the brushes resulting in the motor not functioning correctly . Interestingly the power shift control motors they are selling on EBay for $47.95 look exactly like the spare DCT motor I have.
I'm off: ATW by motorcycle | an AfricaTwin on the loose | Page 2
https://www.africatwinforum.com/att...6748313437938_599377658412793856_n-jpg.49341/
For 2007-2021 Honda Foreman 500 Rancher 420 Pioneer Shift Motor Control Assembly | eBay
 

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I wish I knew if it was the same. For $48 I'd buy one just to guarantee my original would never fail...
 

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I've since put over 600 miles on my new shift motor and have not ran into any problems whatsoever. So replacing the shift motor fixed my issue. It's a shame that a $225 part turned into 3 weeks in the shop only for them to not find a problem. I wasted a lot of money on the labor costs but at the end of the day i have a properly functioning motorcycle now so I'm happy.
 

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Just an update. Since the part was under warranty, Riva had to order it from Honda directly and not through a reseller. They ID'ed the problem on 4/22, and order was invoiced on 4/30. So another week or so for part.
 
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