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Old 10-07-2013, 01:32 PM   #16
High Country Herb
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Originally Posted by cellige View Post
pretbek, perhaps its just my lack of skill but it seems on my bike that even if I crack the throttle on the smallest amount I can, its still not smooth, whereas I can get the power on (in the same amount of time) by engaging the clutch/throttle very smoothly. Is that not common?
You're talking about when the throttle comes back on while the clutch is fully released? Each bike is a bit different when it come to how abruptly it comes back on. You may want to feather the clutch a bit to smooth the power delivery, because rough throttle engagement can upset the suspension in a similar manner as rough shifts.

I enjoy letting the clutch out in each gear while doing rev matched downshifts. Not only is it just plain fun, but it also helps me to develop better use of the controls. I can tell when I'm having a good day when deceleration remains smooth even as I switch back and forth between engine braking and using the brakes. Early in my ride, I will make the decision of how aggressive I am willing to ride that day, and that is one of the indicators.
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Old 10-07-2013, 03:57 PM   #17
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Old 10-07-2013, 04:30 PM   #18
pretbek
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Quote:
Originally Posted by cellige View Post
pretbek, perhaps its just my lack of skill but it seems on my bike that even if I crack the throttle on the smallest amount I can, its still not smooth, whereas I can get the power on (in the same amount of time) by engaging the clutch/throttle very smoothly. Is that not common?
Being smooth with the clutch / throttle engagement is not rare.
I'm just saying (just like the other inmates) that you should be done with it before entering the turn. That way you are already on the throttle when approaching and in the turn (steady speed, same partial throttle opening) and don't spend any brain power on the required smooth coordination of clutch and throttle.
Holding your throttle open at a steady position is more fool-proof than clutch/throttle play, even if you're good at it.
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Old 10-08-2013, 07:09 AM   #19
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Originally Posted by cellige View Post
Someone said it would be a good idea to post in this subforum, so here we go ! Question about downshifting !

Seems to be that the technique used out on the track (mainly without a slipper clutch) is to downshift while braking, releasing the clutch for each gear, finishing your braking/downshifting before you lean the bike, lean the bike and then immediately after done leaning, roll on the throttle.

I would like to know why there is an advantage doing that method instead of: braking, downshifting through each gear with the clutch held in, leaning the bike and immediately after leaning getting the clutch in the friction zone/rolling on the throttle/getting clutch all the way out.

So whats the deal?

Must have been bored on way home from work, was thinking about this peculiar question. One of those that, if you need to ask, you'll struggle with the explanation.

Or perhaps it is the other way around: try this yourself at a track, and you will quickly have the answer with no further words needed.

Anyway, riding home and was going down a few gears for a red light and was reminded that a motorcycle gearbox cannot be relied upon even to change down several gears reliably with the clutch "in". You need the clutch to transmit chain pull from the rear wheel and move the shift dogs a bit or one of your successive prods on the lever might not make a shift.

So that alone is a reason why releasing the clutch a bit while downshifting helps.

The other of course is that at corner apex on the track you are aiming to be going so fast that the tyres are using all their grip just to support you at lean. Idea is you then open the throttle a smidge at first and that is enough to begin a very gentle rear-tyre drift if you get it (i.e. your apex speed) just right.

Obviously trying to do all that while simultaneously releasing the clutch after a multiple downchange adds enormously to the difficulty.

Go slow enough and sure, you will manage it easily.
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Old 10-08-2013, 07:21 AM   #20
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Oh, and on the throttle smoothness thing, some bikes are better than others but on the track, a very smooth transition from no throttle to some is a very desirable thing.

If yours is so bad that it helps you to feather the clutch for control at most apexes, then sure, feather the clutch. But in that case careful tuning could cut a lot from your lap times.
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Old 10-08-2013, 08:02 AM   #21
High Country Herb
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Quote:
Originally Posted by Moronic View Post
If yours is so bad that it helps you to feather the clutch for control at most apexes, then sure, feather the clutch. But in that case careful tuning could cut a lot from your lap times.
Could this also be caused by a loose chain?
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Old 10-08-2013, 08:41 AM   #22
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Originally Posted by High Country Herb View Post
Could this also be caused by a loose chain?
Shouldn't be.

Remember most of the time at the track they will ding you for less than a 1.5 inch chain sag at tech. You ALWAYS run the chain loose so that it doesn't bind the rear suspension.

If the throttle is being that agressive that you can't roll in (and I don't mean from 1,200 RPM more like 4 grand) smoothly you can always drag the rear brake a bit, its something that I have done for years since my Speed Triple is pretty bad with driveline lash.

If you aren't completely off of the throttle it won't lock the rear.
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Old 10-08-2013, 11:11 AM   #23
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Quote:
Originally Posted by Moronic View Post
Must have been bored on way home from work, was thinking about this peculiar question. One of those that, if you need to ask, you'll struggle with the explanation.

Or perhaps it is the other way around: try this yourself at a track, and you will quickly have the answer with no further words needed.

Anyway, riding home and was going down a few gears for a red light and was reminded that a motorcycle gearbox cannot be relied upon even to change down several gears reliably with the clutch "in". You need the clutch to transmit chain pull from the rear wheel and move the shift dogs a bit or one of your successive prods on the lever might not make a shift.

So that alone is a reason why releasing the clutch a bit while downshifting helps.

The other of course is that at corner apex on the track you are aiming to be going so fast that the tyres are using all their grip just to support you at lean. Idea is you then open the throttle a smidge at first and that is enough to begin a very gentle rear-tyre drift if you get it (i.e. your apex speed) just right.

Obviously trying to do all that while simultaneously releasing the clutch after a multiple downchange adds enormously to the difficulty.

Go slow enough and sure, you will manage it easily.
On my Concours 1400 with slipper, I sometimes on the street go down multiple gears without releasing the clutch. I do the same on my KTM 560 SMR and KTM 525 EXC. More so the KTMs than the C14, as the C14 is the street bike and ridden the least aggressively.

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Old 10-18-2013, 01:39 PM   #24
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Quote:
Originally Posted by cellige View Post
.........I would like to know why there is an advantage doing that method instead of: braking, downshifting through each gear with the clutch held in, leaning the bike and immediately after leaning getting the clutch in the friction zone/rolling on the throttle/getting clutch all the way out............
Here are the advantages:
  • The engine braking effect is pneumatic and will never lock the rear tire (unless you over-downshift and release your clutch quickly). While you are holding the clutch in, you have no engine braking effect. Your deceleration to reach entry speed relies only on the brakes. That is fine as long as you don't use much rear brake and lock it.
  • You are sure that each downshift has actually happened and you have boosted engine braking effect after each one. There is harmony between the speed of the bike and the rpms' of the engine. Downshifting without the feed-back of the clutch-out and the resistance on the rear tire is pneumatic can be dangerous if the final actual gear rate does not match your expectancy for any reason (false shifts or false neutrals or just counting mistake). The danger comes from a locked and sliding rear tire. The inconvenience comes from ending in the wrong combination and slowing down. The blipping technique to match rpms' and rear wheel spinning is more difficult to do properly when you drop multiple gears while keeping clutch-in.
  • All the downshifting process is done before the bike is leaned over; hence, any mistake leading to locked rear tire or upset suspension is more forgiving regarding a slide and downside (or even highside) fall. Carefully clutching-out while already leaned over may be good for a smooth deceleration-acceleration transition (regarding suspension and loads on each contact patch), but it takes attention away from the tasks that correspond to that moment: quick flick, relaxed upper-body and arms input to the handlebar, line trajectory, road hazards and throttle control.
Bikes that have fuel injection or excessive slack in the throttle cable, chain and sprocket's coupling may show a rough transition from deceleration to acceleration.
A brief overlap of rear brake application and throttle opening can reduce that jerk effect and smoothly transfer the weight from the front contact patch to the rear.

Trail braking and clutching-out into the turn and after leaned over are fine and delicate techniques not suitable for riders of limited experience.
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Old 10-18-2013, 05:38 PM   #25
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I downshift because I like to have my engine spooled up a bit before entering a turn. I let the clutch out between each shift so I can judge whether I am in the right gear or not, one gear too many could over rev the engine or possibly cause the rear end to step out.

I've never taken any race training, but I like to have the motor wound up in a curve so that I can get some good engine braking if needed and get some good acceleration on my way out. I think that when the motor is spooled you have to stay on the throttle to keep speed, and that keeps driveline lash to a minimum.
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Old 10-18-2013, 07:23 PM   #26
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Originally Posted by kyns View Post
At the track you actually trail the brakes (front brake) all the way to the apex and down shift at the same time.
This another reason I would like to take a track class some day. Dragging a front brake while in a turn or leaned over goes against everything I have been taught and taught. I understand the theory which is fascinating.
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Old 10-21-2013, 02:43 AM   #27
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Originally Posted by Motor7 View Post
This another reason I would like to take a track class some day. Dragging a front brake while in a turn or leaned over goes against everything I have been taught and taught. I understand the theory which is fascinating.

You get style points for doing it clucthless THAT is a real bitch to get right. I almost always clutch unless I'm having a really good day.

...and trailing on the track varies by corner, some corners you do all of the braking straight up and down then tip it and back on the throttle, some you trail pretty deep, some S-turns you you "chop" instead of going wide in wide out you hug the inside after the first corner, and if you do it right you aren't really completely off the brakes until the second apex.

Then you have that rat-bastard lightbulb at NJMP, we like to call it never ending right and never ending left, the right is triple apex 3rd and forth gear into a heavy decreasing radius.....just to swap to never ending left which is 210* 2nd gear and decreasing radius. That third apex you are coming in 4th gear hanging off the bike as far as possible to brake and get downshifted for the decreasing radius, and there isn't room to stand it up if you are going faster than parade lap pace.

Fuck up never ending left you just lost like 3 seconds because its WTF all the way to turn one there.....and its wide enough that there are about 12 different line you can get through the left on.
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Old 10-21-2013, 11:25 AM   #28
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Quote:
Originally Posted by Motor7 View Post
This another reason I would like to take a track class some day. Dragging a front brake while in a turn or leaned over goes against everything I have been taught and taught. I understand the theory which is fascinating.

I think everyone should spend some time at a race track learning how to corner. I just about live at race track for 6+ months of the year and I've done a few different schools. I'm not the fastest, but I'm not slow and anyone who I race with will tell you I'm super smooth.


So my take on braking/downshifting:

Blipping isn't the only method for down shifting and matching revs. The method I pick up from Pridmore's Star school really works best for me. (you can find videos of it on his site) In short, you down shift before you roll off. Sounds odd, I know, but it works. It took me the better part of a two day school to get it, but once I did I wasn't bouncing the back tire on my R6 anymore.

All of my down shifts are complete within the first 10% of braking. But I don't fully release the clutch until I'm ready to tip in. At that point I'm trailing the brakes until I'm comfortable with my speed and that I know I'll hit my apex.

Once at the apex, it's easy to start to pick up the gas as you take away lean angle. Once you can see your exit point and the bike is about upright... it's WFO.
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Old 10-21-2013, 02:13 PM   #29
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I think you never want to freewheel corners in any vehicle. You want the motor connected to the driving wheels as much as possible. Sure, if I am coming to a stop I will simply pull in the clutch and downshift all the way while using the brakes to stop. But never on a track; and almost never if I am not coming to a stop.

Matching gears: Downshifting is a big part of my fun when riding in a spirited fashion. I like to use mostly the front brake when on the tar. I like heavyish front wheel braking with a constant pressure on the lever, while blipping the throttle with the same hand. While I am not a road racer, both of my sons are and I learned that little technique from them. And BTW, they had slippers and speedshifters to help. But the downshifting is a bit of an art that is special for me.

I am pretty abrupt with the clutch, though. I have a bad habit of popping it out. Like bang! A bad habit.
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Old 10-21-2013, 03:52 PM   #30
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You don't have to concentrate on proper gas/clutch control when you are already in the right gear with the clutch fully released.
That way you can focus on other things like apex, exit speed, obstacles and road surface.
The brain can only think of one thing at a time. Where there is more than one thing happening, we can give each item slices of attention. The more we have to think about any one thing, the less time we have to think about other things.

My mechanic said to do clutchless downshifts only in the winter when he needs the money--he's plenty busy in summer.

It can be learned to squeeze the brake lever and roll-on a blip of throttle at the same time for smooth downshifts while braking.
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