Stopping DCT equipped engine

[DCTFAN]

Owner's manual p39

To stop the engine, put gear to Neutral
(N indicator comes on).
>If you turn the ignition switch to the OFF
position when the motorcycle in gear, the
engine will shut off with the clutch
disengaged.

I can't figure out why the text includes the above tidbit??
Is this good or bad?
DCT owners, how do you turn off the engine?

PS. I also want to know, why the parking brake is necessary on the DCT?
When shutting off, why can't the DCT remain in gear with clutch engaged(like manual models)?

 

[DirtFlier]

Try this - Come to a stop, turn OFF the engine, now see if you can roll the bike (meaning it's in Neutral). It might automatically go to N when you turn it OFF?

I know for sure that it goes into Neutral when you turn the key ON but I'm not sure what happens when you turn it OFF.

 

[supertux1]

The DCT is supposed to put the transmission into neutral whenever you turn on the ignition, turn off the ignition or hit the kill switch. It's basically idiot proof, AS LONG AS you have a good battery. I say 'supposed to' because it is an electrical servo powered shifting mechanism (instead of your foot) working against a fairly standard gear box that can sometimes bind like a manual bike does.

Imagine this scenario: You're riding along in sixth gear, you hit a pothole and your battery connection falls off, say because you rushed that last farkle. You instinctively grab for the clutch lever that isn't there and step down on the non-existent shifter peg a few times as you slow down... crap. You're stopped along side of the road in sixth gear. When you restore power and turn the bike back on, the DCT will try to shift it back to Neutral. Since you stopped moving in gear, the gearbox will probably be bound up and the servos aren't going to be able to move the transmission all the way down to neutral. To get back to neutral, you'll have to rock the bike back and forth while turning the ignition on and off so the DCT can step it down one gear at a time.

Edit: The DCT will display a '-' on the dash and the starter button won't work until it gets to Neutral. This is so that you don't go flying away the second you hit the starter button, without having to press the S/D button first.

 

[kpinvt]

The shutdown procedure I always (usually) use follow is: Set the parking brake, hit the neutral button, turn off the key. I never use the kill switch.

 

[Matzergb]

If you use the kill-switch, you can hear the transmission click into neutral. after that you turn the ignition off with the key. If you just turn the key, the transmission will stay "in gear" and only go into real neutral upon starting the ignition again (clicking after the key is turned). At least that's how it works on the 750s.

 

[TigerDude]

The reason to use the kill switch is so you have muscle memory when the throttle sticks

 

[670cc]

The reason to use the kill switch is so you have muscle memory when the throttle sticks

How often does your throttle stick?

 

[dduelin]

The DCT is supposed to put the transmission into neutral whenever you turn on the ignition, turn off the ignition or hit the kill switch. It's basically idiot proof, AS LONG AS you have a good battery. I say 'supposed to' because it is an electrical servo powered shifting mechanism (instead of your foot) working against a fairly standard gear box that can sometimes bind like a manual bike does.

Imagine this scenario: You're riding along in sixth gear, you hit a pothole and your battery connection falls off, say because you rushed that last farkle. You instinctively grab for the clutch lever that isn't there and step down on the non-existent shifter peg a few times as you slow down... crap. You're stopped along side of the road in sixth gear. When you restore power and turn the bike back on, the DCT will try to shift it back to Neutral. Since you stopped moving in gear, the gearbox will probably be bound up and the servos aren't going to be able to move the transmission all the way down to neutral. To get back to neutral, you'll have to rock the bike back and forth while turning the ignition on and off so the DCT can step it down one gear at a time.

Edit: The DCT will display a '-' on the dash and the starter button won't work until it gets to Neutral. This is so that you don't go flying away the second you hit the starter button, without having to press the S/D button first.

What he said.

If we turn off the DCT bike with the key with the transmission in D or S "in gear" there is always a chance the transmission will have a difficult time shifting into neutral upon the next key-on starting sequence. By choosing neutral with the engine still running the shift to neutral is easier on the shift forks and gear dogs. I think that is why Honda suggests that.

The parking brake is necessary because the DCT doesn't leave any gears engaged or "in gear" with the clutch engaged when the key is off and the bike is free to roll downhill and fall over when the side stand retracts. Oil pressure from a running engine is necessary to engage the clutch(es). No pressure the clutch is disengaged. A manual bike can be left in gear and can't roll.

 

[kpinvt]

What he said.

If we turn off the DCT bike with the key with the transmission in D or S "in gear" there is always a chance the transmission will have a difficult time shifting into neutral upon the next key-on starting sequence. By choosing neutral with the engine still running the shift to neutral is easier on the shift forks and gear dogs. I think that is why Honda suggests that.

The parking brake is necessary because the DCT doesn't leave any gears engaged or "in gear" with the clutch engaged when the key is off and the bike is free to roll downhill and fall over when the side stand retracts. Oil pressure from a running engine is necessary to engage the clutch(es). No pressure the clutch is disengaged. A manual bike can be left in gear and can't roll.

^^^^What he said.

 

[GregC]

So if I'm reading this correctly, using the kill switch to turn off the engine before turning off the key guarantees the bike is in Neutral when stopped (and thus avoiding the possibility that the bike has to downshift manually before the next start) ... yes? I use the kill switch all the time (mainly because that's how they told us to do it in the BRC).

 

[ld_rider]

The DCT is supposed to put the transmission into neutral whenever you turn on the ignition, turn off the ignition or hit the kill switch.

I think what actually happens when you shut off a DCT motorcycle that is in gear with the ignition is that the bike remains in gear. At least mine does. That is why when you restart the bike you can hear it hunting for neutral and you have to wait for the green lamp before you can start it back up.

I've never used the kill switch, so I don't know if it handles an in gear kill switch shutdown the same way the ignition switch does. Seem strange that if the only time the bike would go to neutral "automatically" was with the kill switch and <not> the ignition switch. Some backwards engineering there for sure!

 

[ld_rider]

Try this - Come to a stop, turn OFF the engine, now see if you can roll the bike (meaning it's in Neutral).

Just because you can roll the bike doesn't mean it is in neutral. It could mean the clutch is simply disengaged (which is exactly what I think happens when using the ignition switch).

Put your 5.0 liter Mustang GT into first gear. Push down (disengage) the clutch. You can roll the car easily but it is still in gear.
That is similar as to how the DCT works. With the bike turned off (using the ignition switch) it will remain in gear. The clutch is simply not engaged (and the bike can roll).

Not sure if the kill switch would works the same way..

 

[Midnight Rider]

My procedure: neutral with the mode selector, key off, barking break set. Right to left.

 

[spets]

If you just turn off the bike in gear, it will switch to neutral when you turn it back on again. Since you're taxing the battery with startup and priming the fuel pump and all the other initial loads, it is recommended to put it in N before turning it off.

Also, bike is harder to roll when in gear with engine off than in neutral, but you can still move it. That's why there is a parking brake.

 

[DCTFAN]

What he said.

If we turn off the DCT bike with the key with the transmission in D or S "in gear" there is always a chance the transmission will have a difficult time shifting into neutral upon the next key-on starting sequence. By choosing neutral with the engine still running the shift to neutral is easier on the shift forks and gear dogs. I think that is why Honda suggests that.

The parking brake is necessary because the DCT doesn't leave any gears engaged or "in gear" with the clutch engaged when the key is off and the bike is free to roll downhill and fall over when the side stand retracts. Oil pressure from a running engine is necessary to engage the clutch(es). No pressure the clutch is disengaged. A manual bike can be left in gear and can't roll.

That makes sense to me.

Then is the statement below TRUE or FALSE?
The default state of the clutch in manual transmission is 'engaged' while in dual clutch transmissions it is 'not engaged'?

Default state meaning engine off and key off.

 

[dduelin]

That makes sense to me.

Then is the statement below TRUE or FALSE?
The default state of the clutch in manual transmission is 'engaged' while in dual clutch transmissions it is 'not engaged'?

Default state meaning engine off and key off.

The statement is TRUE.

 

[supertux1]

The DCT is a wet clutch, meaning there's no physical contact between discs in the clutch pack. Regular engine oil is pumped in and out via electric hydraulic pumps to increase or decrease each clutches grip. When there's no engine oil pressure, the clutches are free. The second oil filter in the DCT keeps your engine shavings out of the clutches. I believe this wet clutch is the reason why you shouldn't use synthetic oil in this particular DCT. It's good for the engine but too slippery for clutches that rely on some friction in the liquid. Honda cheaped out a bit by making the clutches share engine oil, the could have made it a secondary sealed system with its own transmission fluid spec. But I digress... (I wonder if the VFR or AT is like this too.)


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[dduelin]

The DCT is a wet clutch, meaning there's no physical contact between discs in the clutch pack. Regular engine oil is pumped in and out via electric hydraulic pumps to increase or decrease each clutches grip. When there's no engine oil pressure, the clutches are free. The second oil filter in the DCT keeps your engine shavings out of the clutches. I believe this wet clutch is the reason why you shouldn't use synthetic oil in this particular DCT. It's good for the engine but too slippery for clutches that rely on some friction in the liquid. Honda cheaped out a bit by making the clutches share engine oil, the could have made it a secondary sealed system with its own transmission fluid spec. But I digress... (I wonder if the VFR or AT is like this too.)


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It doesn't work quite like that. A wet clutch is simply defined as a clutch that lives and works in an oil bath. Old fashioned clutches disengage when a lever and a fork separate the clutch plates so no power is transmitted to the transmission. When the clutch is engaged a lever is released and the clutch plates are allowed to press together via the clutch springs and power is transmitted to the transmission. Honda typically installs the clutch in the transmission where it shares oil with the engine and transmission. Most motorcycle are like this, all Hondas I'm familar with, and I think most all Japanese bikes use a wet clutch. Dry clutches are the norm on cars and trucks but rare on motorcycles. BMW boxers use dry clutches except for the newest ones and they have since gone wet since 2014(??) and share oil with the engine/transmission. Moto Guzzi uses a dry clutch too I believe.

Instead of a manually operated lever the DCT uses oil pressure generated by the DCT clutch oil pump to engage and disengage the plates in two clutches via a set of electro-hydraulically operated valves that open and close to route oil under high pressure to the clutch packs. Oil pressure holds the clutch plates apart and disengaged, when the solenoid begins to reduce oil pressure the clutch plates are allowed to come together and the clutch engages.

A torque converter transmits engine power to the transmission via a viscous coupling where the driving and driven parts are physically separate and only connected via an oil bath. Honda uses a torque converter in all automatic transmissions in their cars and one type of automotive DCT but not in the DCT motorcycle 700s, VFRs, and Africa Twin. Honda used a TC in the Honda 750 HondaMatic 2 speed automatic about 40 years ago but not again since. Torque converters are heavy and difficult to integrate into a motorcycle design.

 

[670cc]

Instead of a manually operated lever the DCT uses oil pressure to engage and disengage the plates via a set of hydraulically operated valves that open and close to route oil under high pressure to the clutch packs. Oil pressure holds the clutch disengaged, when the solenoid begins to reduce oil pressure the clutch plates are allowed to come together.

So, if the bike had the key shut off while engaged in, say, third gear, would it be free to roll because high pressure remains in the clutch actuator to keep the plates disengaged?

I believe the question answered earlier implies that the clutches default to being disengaged. You have just described how high oil pressure holds the clutch plates disengaged. That suggests that when a bike is parked and powered off, there is still oil pressure holding the plates apart. So, does it bleed down over time, or hold the oil pressure indefinitely? Does it pose a problem when you disassemble a clutch?

 

[dduelin]

So, if the bike had the key shut off while engaged in, say, third gear, would it be free to roll because high pressure remains in the clutch actuator to keep the plates disengaged?

I believe the question answered earlier implies that the clutches default to being disengaged. You have just described how high oil pressure holds the clutch plates disengaged. That suggests that when a bike is parked and powered off, there is still oil pressure holding the plates apart. So, does it bleed down over time, or hold the oil pressure indefinitely? Does it pose a problem when you disassemble a clutch?

I got it backwards. Oil pressure keeps the clutches engaged. The clutch packs aren't under pressure with the engine off. Replacement is simple as the packs are removed and installed as a unit.