[Sutripta]

^^^
Once again, my comment is on 'harm to the gearbox', not riding techniques.
I would also assume that the rider has correctly chosen a gear consistent with his road speed, but even if not, not really relevant to my query.

Regards
Sutripta

PS - have consistently shifted down twice (and still do) on one clutch pull (on the RD and the baby CBR), essentially before an overtaking maneuver, with no harm to the gearbox.

[Rollin' Thunda]

Originally Posted by Sutripta

That sense eludes me!
What is 'wrong speed', and most importantly, how does it harm the gearbox. Remember the discussion is on not releasing the clutch in between multiple downshifts, and its harmful effects on the gearbox.

Regards
Sutripta

A simple thought experiment: You are travelling at 100 kmph on 6th gear, and then you hold down the clutch and shift down to 1st gear, say, where the same engine RPM gives a speed of 15 kmph. This means that, when you release the clutch, your bike would experience a terrific braking force to slow it down instantly from 100 kmph to 15 kmph. This braking force would not come from the brakes (which you may not have touched!) but from the gear teeth which will therefore have a tremendous impact load, which would certainly degrade, perhaps even break, them. ABS cannot help you, as it only works on the brakes, not on the gears, so you will get into a rear-wheel skid and fall. When you get up from your fall, and if unhurt, you will discover that your gear-box (or at least your first gear) is damaged beyond repair.

That is why it is not a good practice to shift down several gears at once, and why it is a good thing that KTM engineers made it impossible (if Cyrus is right) to do this on the Duke...

[ebonho]

Originally Posted by Sutripta

^^^
Once again, my comment is on 'harm to the gearbox', not riding techniques.
I would also assume that the rider has correctly chosen a gear consistent with his road speed, but even if not, not really relevant to my query.

Regards
Sutripta

I just told you how its going to harm your gearbox and components of your transmission chain. Best case you are going to have bad wear and tear and scalloping of sprocket teeth and premature lengthening (ovaling of roller pin holes) of your chain links. Worst case you are going to be breaking teeth.

Its impossible to match road speed and gear perfectly in correct decrements with multiple shifts - unless as I also said, you just empirically slow down and then labor up.

PS - have consistently shifted down twice (and still do) on one clutch pull (on the RD and the baby CBR), essentially before an overtaking maneuver, with no harm to the gearbox.

That explains it. Responding to your post add-on.

Depends on the spacing of gears in different bikes. Do the same in a 4 speed Bullet from 4th to 2nd and you will experience what I am talking about.

What Ashok was talking about on his Duke (I'm making an assumption here) was shifting down multiple gears (more than 2) from higher gears - say 6th to 3rd or even 2nd.

[Sutripta]

Guys,
You are taking it to the extremes of bad riding technique as an example of bad riding techniques!

Why is everyone assuming that there has to be a massive shock load? (Any rider who rides like that deserves what he gets.)
In a bike the weakest link will be the chain and sprockets. What about the gearbox? Which was my original query. (Lets leave RE gearboxes, actually any part of an RE out of this discussion!)

Regards
Sutripta

[ashkamath]

Originally Posted by Cyrus_the_virus

Both of you are doing it wrong. This is not a problem with the bike, any bike for that matter, please do not try to shift from top to bottom in a single clutch hold, it not only does not work in majority of the bikes, it is a bad practice and harmful for the gear box. The best way to quickly downshift through all the gears is to shift down, let go clutch, again shift down, let go clutch, all this in quick succession. This will not only slow down your bike faster due to engine braking but also protect the gears. If you are going to run on free clutch while downshift you actually end up going faster than slowing down due to zero engine braking. Please avoid this bad practice.

Always keep the right gear engaged for the speed you are doing even when slowing down. If it is an unavoidable emergency situation where you have to come to a complete stop immediately, please do not touch the clutch untill the last moment when you feel the engine is dying. then once you have stopped, shift down and move. Again, running on free clutch will just make you go faster instead of slowing down. Learn to use engine braking alongside your normal brakes.

Hmmm, been away for dinner. Okie. Let us be sensible.
Suppose I am riding at 80 Kmph at 6th Gear. My speed in 2nd gear is generally say 20 Kmph. So if at 80 Kmph speed I downshift rapidly to 2nd gear, then the rpm shoots up beyond the max as the 2nd gear max speed is what? about 80ish or less. and my bike and myself are totalled. Any rider with an iota of grey matter wouldn't do that. Of course I slow down guys.
Let me give a simple scenario. I am doing 80 in 6th gear. I come across a hump which needs the bike to be at say 20-25 Kmph speed. So I apply the brake when I am near the hump, I am not using the clutch, but I use my front brakes mostly than rear brakes up to say about 70-80 Kmph ( it is a habit) . so the bike slows down to say 25-30 Kmph as it touches the base of the hump and now I am still in 6th gear. as I negotiate the hump I start shifting down the gears. I have less than 3 seconds to pass over the hump and move on again. I have 4 shifts to make to come to the right gear that is 2nd gear. This is where I try to shift rapidly without declutching.

Another scenario. I am riding at 80-90 in 6th gear on the highway, I intend t overtake a truck infront of me. I see that a vehicle is approaching. I have to slow down for the vehicle to pass. I apply the brake behind the truck, and as the approaching vehicle passes simultaneously I down shift 4 gears ( remember by that time my bike has slowed down to say 25-30 Kmph because of cutting down the throttle and braking, I get 3 secs to again give throttle.

I can do the clutch-declutch for every gear, but some how that would add a few extra seconds at that period of time.

No guy sane would simply shift the gear from 6th to 2nd if he is doing 100 and I believe I still have my grey matter

and guys there would be another argument that one cannot ride at 20-25 Kmph in 6th gear and the engine starts knocking very badly which is true, so in that case how would I be doing that speed while approaching a hump but still in 6th gear?? I cut the throttle completely as I approach and brake very late almost at the hump (front brake mostly) and the rapid gear shift. It is like a perfect symphony done in a perfect rhythm. smooth..No knocking nothing.. Try it out and let me know

[ebonho]

Ashok I am surprised bro. You are riding the clutch basically. And there is a period of time in your riding where you are freewheeling with the clutch in and no engine control. A LOT longer than the cumulative clutch time making the downshifts towards the 20-25 kmph you need to reach in the first place.

[ashkamath]

Originally Posted by ebonho

Ashok I am surprised bro. You are riding the clutch basically.

Nope Doc. you are wrong. infact I use clutch as less as possible. I brake very late. so I would be maintaining a fair speed till end. and for the same reason that I use clutch minimal, and I throttle gradually and a host of other reasons, I used to get the best mileage on my bikes. Those days over a decade back, on my P-180, myself, venkat and others went on rides to practise some riding techniques and venkat used to always tell everyone- Ashok has some of the best riding practises.

Doc, tomorrow I will try to recreate the exact scenario on the road. will check the speed, the gear, when I use the clutch, brake and will provide some data. Even I will be clear if I am riding the clutch. If I am doing that then I need to change the bad habit asap. But I am the guy who spends minimum time on the clutch always. let me check it out anyway.

[man_of_steel]

Originally Posted by ashkamath

I am doing 80 in 6th gear. I come across a hump which needs the bike to be at say 20-25 Kmph speed. So I apply the brake when I am near the hump, I am not using the clutch, but I use my front brakes mostly than rear brakes up to say about 70-80 Kmph ( it is a habit) .

This was the exact scenario which I intended. Slowing down suddenly for a pothole or hump or let another car/pedestrian/chicken cross the road using the brakes and engine braking. But at the end of the slowing process we have to shift down to a 'suitable' lower gear! Never would have thought that someone here would assume that multiple downshifts are made without slowing down. Some times it will not be possible to release the clutch in between every shift-down.

[ebonho]

Originally Posted by ashkamath

Nope Doc. you are wrong. infact I use clutch as less as possible. I brake very late. so I would be maintaining a fair speed till end. and for the same reason that I use clutch minimal, and I throttle gradually and a host of other reasons, I used to get the best mileage on my bikes. Those days over a decade back, on my P-180, myself, venkat and others went on rides to practise some riding techniques and venkat used to always tell everyone- Ashok has some of the best riding practises.

Doc, tomorrow I will try to recreate the exact scenario on the road. will check the speed, the gear, when I use the clutch, brake and will provide some data. Even I will be clear if I am riding the clutch. If I am doing that then I need to change the bad habit asap. But I am the guy who spends minimum time on the clutch always. let me check it out anyway.

Thanks for clarifying bro. Its clearer what you are doing now, You are however losing out on engine braking as you are in a higher gear for a longer period of time. Because even if you brake late, it is a planned braking, and hence you are therefore going to be either chopping or easing off the throttle before you actually hit the brakes. You are also consequently not in the meat of the power bad for a significant point before you actually shift down ad de-clutch at the end of that. That's first.

Second is since you are finally clutching and dropping a number of gears in a hurry, you are for a period of time (much longer than the final downshift in individual progressive downshifts) actually freewheeling without any engine and still on the brakes (dangerous) at the exact final moment (either almost on the corner or bump or overtaking maneuver) when you actually need most to be in the right gear and in the middle of the meaty part of the powerband - with engine engaged.

Yes I do agree that you will get better mileage from your way of riding. Which is why I probably get a km or two lower than norm in all my vehicles - car or bike.

Hope this is clearer. There is no one correct way and I am merely sharing my take with an equally senior and tenured rider.

[ashkamath]

Originally Posted by ebonho

Thanks for clarifying bro. Its clearer what you are doing now, You are however losing out on engine braking as you are in a higher gear for a longer period of time. Because even if you brake late, it is a planned braking, and hence you are therefore going to be either chopping or easing off the throttle before you actually hit the brakes. You are also consequently not in the meat of the power bad for a significant point before you actually shift down ad de-clutch at the end of that. That's first.

Second is since you are finally clutching and dropping a number of gears in a hurry, you are for a period of time (much longer than the final downshift in individual progressive downshifts) actually freewheeling without any engine and still on the brakes (dangerous) at the exact final moment (either almost on the corner or bump or overtaking maneuver) when you actually need most to be in the right gear and in the middle of the meaty part of the powerband - with engine engaged.

Yes I do agree that you will get better mileage from your way of riding. Which is why I probably get a km or two lower than norm in all my vehicles - car or bike.

Hope this is clearer. There is no one correct way and I am merely sharing my take with an equally senior and tenured rider.

Doc, I agree fully what you said above, both the point 1 and 2. First I am losing on the power band and instead of doing it linearly and still retain all the juice within the power band I am kinda losing it out.. and the second,yup freewheeling for a longer period of time without engine engaged at that juncture is not advisable one. Gotta do it right bro as you said. have to unlearn something now. It helps to be an empty cup in matter of learning.. you can always learn better ways of doing things. Tnx man

[Cyrus_the_virus]

woot! I was away for dinner and 2 pages already

@ebonho, thanks for clarifying the points doc.

Like I and ebonho mentioned in the above posts, depending on scenario, the action would be different but the tumb of rule is avoid downshifting from top to bottom at one go because the clutch is not 'neutral'. Some of you might understand when I say that when you pull the clutch, the drivetrain is not fully disengaged, there is a slight amount of gear friction. This you can test by pushing your bike in gear while holding clutch and then pushing it on neutral. You will see the difference here. Now, when you do multishifts from the top on a single clutch pull, if you have not exactly slowed down to the powerband/wheel-to-engine speed of that gear before engaging it, you will hear essentially a big clunk/thud, basically the sound of two differential speed clogs coming together. Here is where you can cause gear teeth damage because the flywheel and that gear cog are running at differential speeds before it comes together even when you are holding the clutch. At the same time if you wait for too long in clutch before you change to the right gear, essentially there will not be enough momentum for the gear cogs to disengage and move down which is what essentially gives you the feeling of a ghost gear or the gear just refusing to click down. This is why it is essentially to move to each gear at it's designated powerband/engine-to-wheel speed.

@Ashok, the premise of the argument was to point out that the lack of multi dowshift on a single clutch pull is not a mechanical problem with the Duke and it isn't going to get any better if you change any oil or take to any mechanic to fix it. Now is your opportunity to dump the bad practice and get into the practice of the standard quick downshifts.

So more than the argument of whether anyone have the right to downshift whichever way they want, please understand that the Duke not allowing you to multishift in a single clutch pull is not the bikes fault.

Having said that, if you are overtaking a slow vehicle, stay behind it till you gradually shift to the right gear and then accelerate rather trying to shift down all at one go before you overtake because as mentioned from the above several post, this is not only a wrong practice but also unsafe in several degrees.

If you have to suddenly slow down for a speed bump from 6th gear, hit the brakes and pull the clutch just before you start to hear it stalling/tire locking, then once you have crossed the bump, as you decide to accelerate, downshift one, give a little bit of gas and let go of clutch very slightly and pull it back immediately, downshift one more, let go of clutch lightly and pull back, repeat till you get to the right gear. You may even try 2 gear at a time but not more than that. The whole point is you should avoid downshifting 6th to 2nd or 1st at one go while you are 'slowing down' rather you should do it while you are trying to 'accelerate' out of what ever reason you slowed down in the first place for because of the simple fact that no matter how good a driver you are, if you are trying to downshift multiple gears at one clutch go whilst trying to slow down, you are riding clutch and not slowing down rather going faster than your mind perceives you are and now you have already arrived at the point 30Kmph faster than you should be and you are in a phantom gear.

[Added_flavor]

Nice discussion this! My 2 cents.

1. You're doing it wrong if your shifting down thud thud instead of a click click. If you're in a situation where you're too fast for a lower gear, blip the throttle and shift down for a smoother or near perfect 'click' shift.

2. Shift down the way you shift up according to the vehicle speed. Be in neutral before you come to a complete halt.

Edit: Cyrus has written a more elaborate version of what I meant to say!

[ebonho]

Originally Posted by Added_flavor

1. You're doing it wrong if your shifting down thud thud instead of a click click.

This is the bottom line.

Wonder why you did not come earlier and save us from typing out such long posts!

P.S. Sound-wise though, I'd go with Cyrus's description of a clunk clunk over a thud thud.

[ashkamath]

Originally Posted by Cyrus_the_virus

@Ashok, the premise of the argument was to point out that the lack of multi dowshift on a single clutch pull is not a mechanical problem with the Duke and it isn't going to get any better if you change any oil or take to any mechanic to fix it. Now is your opportunity to dump the bad practice and get into the practice of the standard quick downshifts.

So more than the argument of whether anyone have the right to downshift whichever way they want, please understand that the Duke not allowing you to multishift in a single clutch pull is not the bikes fault.

Cyrus, I have done this multi gear down shift on almost all bikes I have ridden without any issue of sticky gear shift. ( I agree that it is not a good biking practise and outright unsafe, but the issue I am having is about sticky gear shift. Now I do not buy your point that duke is not allowing me to multi shift in a single clutch pull. My premises is simple, If I shift a gear to a lower gear, the lever should retract to it's normal position as soon as I am done with it. period. It is as simple as that. Even though I gave the example of multi-down shifting, I have this sticky gear shift even doing normal single gear shifts. and having never experienced any sticky gear shifts in all my other rides, I believe I am taking this matter with SVC guys very soon.

regarding the oil change it is because my bike has done over 2200 kms since last service and I want to change the engine oil for a different grade and it is a personal matter of choice and not connected with this issue. but yes I was keen to know if change of gear oil would help

Having said that, if you are overtaking a slow vehicle, stay behind it till you gradually shift to the right gear and then accelerate rather trying to shift down all at one go before you overtake because as mentioned from the above several post, this is not only a wrong practice but also unsafe in several degrees.

Cyrus, the road presents umpteen scenarios and variations for riding, so one cannot have one rule for everything. while I agree to your staying behind a slow vehicle it till you gradually shift to the right gear and then accelerate, there are times when I don't want to stay behind a vehicle (coz I see a trail of vehicles coming in the opposite side at a not far off distance and I want to pass this truck asap), and I have braked hard and my speed is down to 20 Kmph, at this juncture, my 5th or 4th or even 3rd gears will just knock and wont pull me out of that situation. at that very moment I need to be in 2nd gear ( being in the right gear in the right speed) to bail me out.

If you have to suddenly slow down for a speed bump from 6th gear, hit the brakes and pull the clutch just before you start to hear it stalling/tire locking, then once you have crossed the bump, as you decide to accelerate, downshift one, give a little bit of gas and let go of clutch very slightly and pull it back immediately, downshift one more, let go of clutch lightly and pull back, repeat till you get to the right gear. You may even try 2 gear at a time but not more than that. The whole point is you should avoid downshifting 6th to 2nd or 1st at one go while you are 'slowing down' rather you should do it while you are trying to 'accelerate' out of what ever reason you slowed down in the first place for because of the simple fact that no matter how good a driver you are, if you are trying to downshift multiple gears at one clutch go whilst trying to slow down, you are riding clutch and not slowing down rather going faster than your mind perceives you are and now you have already arrived at the point 30Kmph faster than you should be and you are in a phantom gear.

What I understand from your saying is that, if I am in 6th gear and hit a hump, I hit the brakes ( right), pull the clutch just before you hear the stalling ( right) and cross the bump (wrong because you are crossing the bump with clutch engaged) and as you decide to accelerate, downshift one i.e. to 5th gear (which wont have any juice to pull at 20 Kmph)and a little bit of gas and let go of clutch very slightly and pull it back immediately, downshift one more, let go of clutch lightly and pull back, repeat till you get to the right gear.

So that essentially means you are engaging the clutch between 6th gear and 5th gear while passing the hump, and then gradually you will downshift to 5th give a little gas -declutch-then to 4th - give a little gas- then declutch- then to 3rd -give a little gas- declutch - then to 2nd gear and then accelerate.
If that is what you meant, then that means either you have approached the hump at a very high speed ( then it makes sense), if you are already hit the brake and very slow, then the above exercise will simply create knocking in the higher gears.

If that is what you meant (as I understand from your reply), then I dispute your way of riding the hump.

if you are trying to downshift multiple gears at one clutch go whilst trying to slow down

Boss I never said I am downshifting multi gears while trying to slow down. I said once I hit the brake and I am at a slow speed, but a higher gear I multi-shift to arrive at the right gear.

I agree to Doc when he said that approaching the hump with brakes and appropriate engine braking and arriving at the hump at the right / slightly more / at the right gear / one up gear is the way to ride and not riding the hump with clutch engaged between 5th and 6th gear. I would never do that. I would never ride over a hump with clutch engaged. it will always be with engine power ( in gear)

Guys it is not that I am trying to say that the way I am riding is correct or defending my view point. I agree fully that multi-gear shift in a single clutch is not a good practise and is unsafe too. I shall definitely unlearn this practise and change to better riding practise. Thanks to all of you, for helping me in this regard.

[JayPrashanth]

Multiple downshifting is definitely ok if you know you're coasting to a stop. Slick gearboxes like the ones on most Yamahas lend themselves to such antics without the accompanying clunks/thuds. What I find strange is the Duke 390's lever not retracting back. This is definitely not a safety measure or an engineering design.

Cheers,

Jay