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A thread for us DCT owners, please use these posts ONLY for helping others understand the way our bikes operate. NOT for complaining on how they work. Hopefully we can share information and help those new to the DCT..
Also please include the year/ model of the bike’s DCT you are posting about.
Thanks!
 

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Discussion Starter #2
My 2018 ATAS
Using “D” mode and the short shift issue:

For most parts “D” mode shifts more like “normal” at or above 2500 RPM,
It is optimized for fuel economy and more open area riding.
 

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Discussion Starter #3
My 2018 ATAS

Found slight differences in the TC control when in different modes of “S”1 ,2,3
Found I could skim the front wheel of the ground ( small wheelie’s) in “S”-3 but not in
S-1 when the TC was set at 1 in both cases.
Lol it actually took me a bit by surprise.
The only time I can recall TC-1 kicking on was roosting in deep mud. And usually I’m in S-3 for around town driving.
 

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So far the only DCT "issue" I have experienced so far is something along the lines of:

Although Drive Mode works well, I have found that if you accelerate really hard (e.g. after completing a turn), the DCT tends to "stick" in first gear on its own for too long. This is annoying, but fixable instantly by (+) upshifting. If you accelerate hard, but somewhat gradually, this does not appear to happen in Drive Mode. As a note, I do have the Torque Mode set to "6" and Power set to "1" or "2".

I am still determining if this is "rider-related" in regards to how the DCT behaves under this condition, or something else.

I will add that I was in "Tour" mode each time.

2019 Model.
 

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The DCT D mode on my 2017 bike was just slightly dull and so I would often slip it into s2 mode for overtaking. However, my 2018 ridebywire model with the engine power set to level 1 (fastest takeup) is a joy to ride in D mode with enough acceleration for all normal overtakes then it slips back into relaxed touring mode. I have set this up as my custom map (power 1, engine braking minimum, TC maximum). If the roads are greasy or it's near freezing I put the bike in Gravel mode. As long as I leave the screen selector cursor on the riding mode line, it means I can change between these two modes (custom and gravel) with just an up or a down on the rocker switch.
Mike
 

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The DCT D mode on my 2017 bike was just slightly dull and so I would often slip it into s2 mode for overtaking. However, my 2018 ridebywire model with the engine power set to level 1 (fastest takeup) is a joy to ride in D mode with enough acceleration for all normal overtakes then it slips back into relaxed touring mode. I have set this up as my custom map (power 1, engine braking minimum, TC maximum). If the roads are greasy or it's near freezing I put the bike in Gravel mode. As long as I leave the screen selector cursor on the riding mode line, it means I can change between these two modes (custom and gravel) with just an up or a down on the rocker switch.
Mike
Since this is a technical discussion thread and I got no pressing matter, here's my 2¢:
...
Also please include the year/ model of the bike’s DCT you are posting about.
Thanks!
Good to make this distinction as 2016=2017 and 2018=2019 with 2020 being evaluated by early adopters aka "guinea pigs";)
IMO, there needs to be a distinction between [ Power Modes ] and [ AT Modes] in this discussion to prevent some confusion.
AT Mode has been described in the 2016/7 manual as the familiar D, S1, S2, S3.
Power Modes are described in the new manual as Riding Modes.
Yes. I find the nomenclature confusing but that is not new from Honda.


So far the only DCT "issue" I have experienced so far is something along the lines of:

Although Drive Mode works well, I have found that if you accelerate really hard (e.g. after completing a turn), the DCT tends to "stick" in first gear on its own for too long. This is annoying, but fixable instantly by (+) upshifting. If you accelerate hard, but somewhat gradually, this does not appear to happen in Drive Mode. As a note, I do have the Torque Mode set to "6" and Power set to "1" or "2".

I am still determining if this is "rider-related" in regards to how the DCT behaves under this condition, or something else.

I will add that I was in "Tour" mode each time.

2019 Model.
The Throttle-By-Wire changed some of the earlier DCT behavior but
what remains the same is that DCT shifting is determined by the "AT modes" (D, S1, S2, S3).
AT modes as Honda called it previously, only change how the bike shifts.
 

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Discussion Starter #7 (Edited)
Since this is a technical discussion thread and I got no pressing matter, here's my 2¢:

Good to make this distinction as 2016=2017 and 2018=2019 with 2020 being evaluated by early adopters aka "guinea pigs";)
IMO, there needs to be a distinction between [ Power Modes ] and [ AT Modes] in this discussion to prevent some confusion.
AT Mode has been described in the 2016/7 manual as the familiar D, S1, S2, S3.
Power Modes are described in the new manual as Riding Modes.
Yes. I find the nomenclature confusing but that is not new from Honda.




The Throttle-By-Wire changed some of the earlier DCT behavior but
what remains the same is that DCT shifting is determined by the "AT modes" (D, S1, S2, S3).
AT modes as Honda called it previously, only change how the bike shifts.
Thanks good points.
Also I will add (just to state the obvious) as DCTFAN pointed out about D,S1,S2,S3 being the one thing that changes the shift patterns/timing, all the “ride modes” Touring”,”Urban”,”User” ONLY are are presets for the “P”,”EB”,”T”. The user one of course being one where you can set your own presets.

18ATAS:

All 4 “drive modes”have a set different minimum RPM shift points, but, that point will change in reference to where the throttle is. So if in ‘D” mode and you take off at a higher RPM then it’s programmed point, which in “D” is pretty low, but let’s say you throttle up to 3000 RPM the DCT will then use that as it’s shift point, shifting to 2nd,3rd,4th,5th,and then 6th all at 3000RPM. It will do this in all drive modes, but of course in each of the modes you can’t shift earlier than the set point. That said, at certain points when you are already real close to a shif point you can go up one gear, but, it will eventually shift back down.
Now “EB” and down shifting have its own set of rules. In general, the “S” modes of course have a more aggressive set down shifting pattern. These of course are all set so that the bike can’t over rev. if or when you manually paddle down a gear. These down shift points will very on the “EB’ setting but generally will mirror the set “up shift” points. So if the mode the bike is in currently will shift at say 4000rpm, when the bike gets to a certain point below 4000rpm, let’s just say 3000rpm it will down shift and will spike back to 4000rpm. The “EB” will move these set points. Example:a lower “EB” setting will will down shift at 2500rpm and spike out at 3500rpm. In all this the bike will NOT downshift and cause the RPM’s to go past the highest set ship point in the system. Now in all this I’ll add; the down shift points in “D” mode are... Well really low, so much so it makes you wonder if it is ever going to go down a gear when decelerating. But it does have the same “rules” as the “S” mode.
These are the basic rules and have a LOT of other variables that will act upon and influence or change those rules, like for example the decent feature that will hold the lower gear while going down a slope and bike speed to RPM ratio...
 

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Hmmmm ... are we sure that the EB mode setting is not changing something in the way the engine behaves rather than just the gearbox. I drive in D mode almost all the time and I love to have as little engine braking as possible. I can notice a difference between EB 1 and EB3 and it does not feel like gear change points. I thought someone said it was something to do with the butterflies?
Mike
 

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AFAIK, both engine braking and throttle action will alter shift points.
Specific to AT/DCT is designed to shift according to what the sensors feed back to ECU.
 

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Discussion Starter #10
Hmmmm ... are we sure that the EB mode setting is not changing something in the way the engine behaves rather than just the gearbox. I drive in D mode almost all the time and I love to have as little engine braking as possible. I can notice a difference between EB 1 and EB3 and it does not feel like gear change points. I thought someone said it was something to do with the butterflies?
Mike
18ATAS.
You are right.
In down shifts the gear box is changing the way the engine reacts.
But
In up shifts the engine is changing the way the gear box reacts..
Also
There is a difference in them (EB1-3) in D mode.
And between S-1 EB1-3
And between S-2 EB1-3
And between S-3 EB1-3

basically the more aggressive the up shift mode the more aggressive the down shifts .
And you can adjust the degree in each case.
 

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And a picture is worth- about a thousand words :)
shift mode vs throttle.jpg

The above graph was published with the 2016 release and shows the baseline differences in shifting among different modes.
The introduction of TBW creates an additional such graph per EP and EB mode combinations- so eight (nine-1) additional shifting behavior.
As mentioned above, other factors such as uphill/downhill and "curvy roads" will dynamically alter shifts also.
Conceptually it is as simple as it gets but the execution appears fairly complex or vice versa.
 

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AFAIK, both engine braking and throttle action will alter shift points.
Specific to AT/DCT is designed to shift according to what the sensors feed back to ECU.
I don't think that the EB and EP settings are implemented through gear shift change points (if that's what you guys still seem to be saying). It seems to me that Honda HAVE done something that produces less resistance to the pistons going up and down when engine braking is set to minimum. And this forum has said that the high power EP setting is accomplished by the ecu telling the throttle bodies to open faster for a given turn at the grip than they would if the EP was set on low. Some have called this a change in the 'ramp'. I'm not totally convinced by this, but in neither case is the effect due to changes in the DCT gear change points.
If that was what was happening with EP and EB, then those modes would have no effect for a manual bike.
Mike
 

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I don't think that the EB and EP settings are implemented through gear shift change points (if that's what you guys still seem to be saying). It seems to me that Honda HAVE done something that produces less resistance to the pistons going up and down when engine braking is set to minimum. And this forum has said that the high power EP setting is accomplished by the ecu telling the throttle bodies to open faster for a given turn at the grip than they would if the EP was set on low. Some have called this a change in the 'ramp'. I'm not totally convinced by this, but in neither case is the effect due to changes in the DCT gear change points.
If that was what was happening with EP and EB, then those modes would have no effect for a manual bike.
Mike
"I don't think that the EB and EP settings are implemented through gear shift change points..."

I think it's the other way around.
Different shift points are effected by different EP and EB levels.
You are correct in how different levels of EB and EP is accomplished- via control of the throttle opening angle (TBW).
In 2016 models without TBW all you got was 100% all the time. So as I posted above, one shift mapping for all the AT modes (D, S1, S2, S3).
TBW takes over and gives a percentage of the maximum for both EP and EB- now we have nine different shift maps.
.
For newer 2020 models with IMU (inertial measurement unit) the is another level of DCT integration that is quite exceptional, I would think.
Can't wait for a test ride on 2020 model.
 

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Discussion Starter #14 (Edited)
I don't think that the EB and EP settings are implemented through gear shift change points (if that's what you guys still seem to be saying). It seems to me that Honda HAVE done something that produces less resistance to the pistons going up and down when engine braking is set to minimum. And this forum has said that the high power EP setting is accomplished by the ecu telling the throttle bodies to open faster for a given turn at the grip than they would if the EP was set on low. Some have called this a change in the 'ramp'. I'm not totally convinced by this, but in neither case is the effect due to changes in the DCT gear change points.
If that was what was happening with EP and EB, then those modes would have no effect for a manual bike.
Mike
18ATAS:
The only way on a combustion engine to actually limit compression (less resistance to the pistons) is electronic valve control or compression bypass.
What you are feeling is basically the ECU more closely syncing the speed of the wheels, the speed of the gear box and the RPM’s of the engine. So when it drops down a gear there is less resistance.
Ramp effect is totally possible in throttle by wire and it is on our bikes, AKA blipping, when the ECU senses the rpm of down shift is a lot faster then the rpm of the engine it will “gas “ the engine for a second to help sync the gears to the speed of the engine. It only does this on the most aggressive EB setting’s. Or brothers on their manual’s do this by releasing the throttle, pulling in the clutch, dropping a gear, tapping the throttle up (blip) and at the same time they release the throttle, they let out the clutch, hence the term blipping...
BTW yes you can sort of get kind of a same effect of compression release by ramping and it will produce a less aggressive EB, but if you actually watch the timing of when the ECU shifts you’ll see that this is not the case in our AT’s.
Example;
Doing 50mph in 6th at high EB in “S” mode and release the throttle and at about 45mph it will start to shift down to 5th and so on..
Doing 50mph in 6th at a low EB in “D” mode and release the throttle and at about 30mph it will start to shift down to 5th and so on.
If the ECU was ramping to adjust the EB the shift timing would be constant (there would be no reason to have different timing)..

I will add you are correct in ramping limiting the engine power, that is how it works. Technically it doesn’t really limit the actual horsepower it limits the reaction speed at which it can be attained, so it is less aggressive and to that end feels like less horsepower,
it’s one of the strange quirks of HP & torque...

.
 

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well it feels the opposite on my bike. I had a 2017 bike (with no possibility of EB or EP adjustment). The 2018 bike was transformed and took off like a rocket when run with engine power1 (ie max ramping?). I think your argument above would have implied that the 2018 bike would have behaved exactly like the 17 bike in max power mode and altering EP to any of the other settings would have just made it gentler. That's not my experience.
And my experience with the engine braking is somewhat similar - minimum engine braking on the 2018 model seems to be different and softer than was possible with the 2017 bike. Although I admit that this effect is more difficult to evaluate as the difference was not as noticeable as for the extra surge in engine power
Mike
 

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well it feels the opposite on my bike. I had a 2017 bike (with no possibility of EB or EP adjustment). The 2018 bike was transformed and took off like a rocket when run with engine power1 (ie max ramping?). I think your argument above would have implied that the 2018 bike would have behaved exactly like the 17 bike in max power mode and altering EP to any of the other settings would have just made it gentler. That's not my experience.
And my experience with the engine braking is somewhat similar - minimum engine braking on the 2018 model seems to be different and softer than was possible with the 2017 bike. Although I admit that this effect is more difficult to evaluate as the difference was not as noticeable as for the extra surge in engine power
Mike
You're exactly right. I have noticed the differences btwn 2016 vs 2019.
I think there was a lot of 'tweaking' the algorithms enabled by TBW and the programmers took advantage, as they should.
It is a bit frustrating we cannot be certain of things in the absence of published information from Honda but the proof is in the pudding.
As you stated, the improvements are subtle but nevertheless can be felt when riding.
 

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18ATAS:
The only way on a combustion engine to actually limit compression (less resistance to the pistons) is electronic valve control or compression bypass.
What you are feeling is basically the ECU more closely syncing the speed of the wheels, the speed of the gear box and the RPM’s of the engine. So when it drops down a gear there is less resistance.
Ramp effect is totally possible in throttle by wire and it is on our bikes, AKA blipping, when the ECU senses the rpm of down shift is a lot faster then the rpm of the engine it will “gas “ the engine for a second to help sync the gears to the speed of the engine. It only does this on the most aggressive EB setting’s. Or brothers on their manual’s do this by releasing the throttle, pulling in the clutch, dropping a gear, tapping the throttle up (blip) and at the same time they release the throttle, they let out the clutch, hence the term blipping...
BTW yes you can sort of get kind of a same effect of compression release by ramping and it will produce a less aggressive EB, but if you actually watch the timing of when the ECU shifts you’ll see that this is not the case in our AT’s.
Example;
Doing 50mph in 6th at high EB in “S” mode and release the throttle and at about 45mph it will start to shift down to 5th and so on..
Doing 50mph in 6th at a low EB in “D” mode and release the throttle and at about 30mph it will start to shift down to 5th and so on.
If the ECU was ramping to adjust the EB the shift timing would be constant (there would be no reason to have different timing)..

I will add you are correct in ramping limiting the engine power, that is how it works. Technically it doesn’t really limit the actual horsepower it limits the reaction speed at which it can be attained, so it is less aggressive and to that end feels like less horsepower,
it’s one of the strange quirks of HP & torque...

.
I don't think the 'blipping' on downshifts in 2018+ DCT models were put in for the reasons necessary as in manual transmissions.
The basic workings of the DCT (with respective odd&even gear shafts)
negates the need to rev-match- the next gear is always preselected

.
 

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Discussion Starter #18
I don't think the 'blipping' on downshifts in 2018+ DCT models were put in for the reasons necessary as in manual transmissions.
The basic workings of the DCT (with respective odd&even gear shafts)
negates the need to rev-match- the next gear is always preselected

.
Agreed, I personally think that Honda added it purely for aesthetics. With dual clutches it is not helpful at all, because there is no “gap” between gears..
 

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Discussion Starter #19
I just assumed ramping simply because it is the quickest and easiest way to limit power.
 
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