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When do you clutch shift?

Started by FireInTheHole, June 02, 2008, 07:22:15 AM

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He Man

If you blip the throttle without the clutch that would just jerk the bike forward though?
2006 Ducati S2R1100 Yea.... stunttin like my daddy CHROMED OUT 1100!!!!


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ROBsS4R


On the street I clutchless up shift when Accelerating Fast and clutchless down shift rarely. To much Engine braking or I need to lug the bike to have a smooth clutchless down shift.

On the Freeway I clutchless shift up and down about 90% of the time.
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Capo

Quote from: bluemoco v2.0 on June 10, 2008, 08:12:01 AM
Being able to shift w/o the clutch can be a handy skill to have in your riding repertoire.  (even if you're not good at it)

I've known riders who have 'limped' their bikes home after a spill -- their clutch levers broke off...

Ah the days of cable operated clutches that broke.


Capo de tuti capi

Greg

Quote from: Stillie on July 01, 2008, 03:30:53 PM
I have no idea what quickshifter works with Monster applications but I know you can get it in two flavors, stand alone and PCIII USB. Both operate in the same manner and momentarily cut the ignition while you're shifting. The one I had plugged directly into the expansion slot on the PCIII and required no additional modifications. I know that the standalone requires some sort of mods to work with the ignition but I'm not sure what. You should be able to find that info on Dynojet's website.

It is the greatest thing since sliced bread and I'll definitely be getting mine repaired once I get around to it. :)

There is a third flavor - also known as the rev limiter  [evil] Preload the shifter before hitting the rev limiter and then when the engine kills the power you have an automatic upshift ;D
2012 M1100 Evo with Termis

TCK!

I still find myself clutching around most of the track, but any open straightaways I clutchless upshift to try and save some time. Using my GPS laptimer I'm able to see how much longer I am decelerating (not on the gas), when I clutch shift. I'm able to drastically reduce this "off the gas" time by clutchless shifting.

He Man

Quote from: RST on July 13, 2008, 09:23:34 PM
Alright, let's keep it simple.

Scenario 1: You're cruising in sixth gear at, say, 9.000 rpm.  You blip the throttle without doing anything else.  What happens?  The rpms climb rapidly and the bike lurches forward.

Scenario 2: For this one we'll assume no throttle.  You're coasting in sixth gear at 9.000 rpm.  You try to downshift, but the bike won't readily pop into the next lower gear because of the load on the gears.  You force the downshift to happen anyway.  As soon as the lower gear pops into place the engine is still revving at 9.000 rpm, but the rear tire is now spinning too fast for your engine speed.  Two things can physicallyhappen to fix this situation: a) your engine revs can climb to match the rear tire speed of b) your rear tire can slow down.

In this case, the weakest link in your chain of resistance is rear tire traction.  The rear tire is going to brake traction and skid along until it's slowed down enough to spin in unison with the engine.  While this is happening, it is reasonable to expect you to feel like you're being thrown forward as you've described.  After all, your rear tire is locking up and decelerating the bike.


To fix Scenario 2, we have to bring the engine rpms up to match rear tire speed as soon as the downshift happens.  We achieve that by simply doing both things at the exact same time: we downshift while blipping the throttle - the lower gears slips in place while we raise the rpms to match rear tire speed.

To be perfectly smooth, everything has to happen with a purpose and at the exact right time.  You do have to be firm without brutalizing the mechanics.  Imagine you're leading in a waltz: you don't want to confuse your partner with wishy-washy input.  Tell the bike in unmistakable terms what it is you want it to do, but tell it gently.  It's the old iron-fist-in-a-velvet-glove thing.

You will want to initiate the shift at the exact moment when there is no load on the gears.  If you're still accelerating, the bike won't downshift because of the forces that the engine is still putting on the gears.  If you're decelerating, the transmission won't want to shift either because of the decelerating forces that are now being applied to the gears.  You want to find the exact moment between acceleration and deceleration when no external forces are being applied to the transmission to initiate your shift.

At the same time, during the fraction of a second that it takes to slip the transmission into the next lower gear, you need to bring the engine rpm up to match the rear tire rpm by quickly and sufficiently blipping the throttle.  Once again, you blip too much and the bike will lurch forward.  You blip too little and the rear will get squirmy again.

Now you've just performed your first clutchless downshift.  I'm sure there will be room for improvement, most notably the amount of how much to blip and how quickly to do it.

All this sounds a lot more complicated than it is once you try it.  To begin, try this exactly: from sixth gear at a fairly high rpm, downshift to 5th without braking.  You can easily practice this on the freeway.  Be aware of traffic around you and don't just suddenly slow down.

The 6-5 shift at high rpms is particularly easy.  After that, work your way down to 3-2.  You'll notice that you have to blip it a little more, because the spacing between 2nd and 3rd gear is bigger than between 5th and 6th so you have to make up a bigger difference in rear wheel and engine rpm.

Once you've mastered the 3-2 downshift, try multiple downshifts at the same time.  Then add the brake, and so on.

I hope this helps a little.  All of the above is for informational purposes only.  Don't believe anything you read on the internet.  Always apply common sense and sound judgment in everything you do.  If you hurt yourself or your bike, it's your own fault.

Have fun practicing,

-R.


Tried it yesterday and lord behold it works! If you get it in the right RPM zone, its REALLY smooth. What I understood from what you said, was a bit diff from what i experience. I didnt blip the throttle per say, but if you stay off the throttle, the engine is locked, and rpms keep droping, if you give it just enough gas to stop the rpms from droping for that split second, the gear drops in easily.basically the same way as clutchless upshifting. still i woudlnt do it with high rpms without a slipper clutch. i broke loose going from 3rd to 2nd at 6000rpms, when i tried it at 4000rpms it worked great. I still 2 finger the clutch, pull it half way, blip and drop. Its alot smoother that way. no jerking. but will practice it downshifting for the lower rpms.

Also if i was crusing at 6th gear at 9,000rpms, my engine would blow up from slamming into the revlimiter for hours on end. (2v) or id be going to fast to be considered crusing, more like running from the cops'ing
2006 Ducati S2R1100 Yea.... stunttin like my daddy CHROMED OUT 1100!!!!


Check out my Latest Video! 05/13/2017 :https://www.youtube.com/watch?v=P4xSA7KzEzU

ghosthound

i just recently started clutchless downshifts (i have been clutchless upshifting since the begining).  Before i tried it, i would clutch, revmatch/shiftdown, release clutch and sometimes it would come out smooth but sometimes it would lurch or jolt because of incorrect throttle.  call me crazy, but clutchless downshift seems a lot smoother than using the clutch.  I feel next to no jolt when i downshift without the clutch.  IMHO this seems like it would be less strain on the transmission. 

red baron

"I believe there are more instances of the abridgment of freedom of the people by gradual and silent encroachments of those in power than by violent and sudden usurpations... James Madison

superjohn

I almost always use the clutch, unless I'm on the SS and my left hand starts to cramp.

TCK!

Quote from: TCK! on July 28, 2008, 06:12:48 AM
I still find myself clutching around most of the track, but any open straightaways I clutchless upshift to try and save some time. Using my GPS laptimer I'm able to see how much longer I am decelerating (not on the gas), when I clutch shift. I'm able to drastically reduce this "off the gas" time by clutchless shifting.

With more time on the track I'm not using the clutch at all except to downshift. But I'm going to try to stop that as well.... We'll see how that goes though.

Fresh Pants

Was playing with clutchless upshifts today after reading this thread. Whee!!!
It's a lot more fun at WOT (smoother/easier?), but today was my first real attempt.

Fun. :D
Bwooooooahhh
Braaaaaaaappp

JetTest

No clutch up or down is no problem, but about 98% time I have two fingers on the brake and clutch, but then I never use more than that anyway. Clutch and brake, even on my 2002 620 never seemed very hard to me.

ghosthound

Quote from: JetTest on January 07, 2009, 11:48:52 AM
No clutch up or down is no problem, but about 98% time I have two fingers on the brake and clutch, but then I never use more than that anyway. Clutch and brake, even on my 2002 620 never seemed very hard to me.

im not quite sure i know what you mean.  People dont clutchless shift because the clutch is difficult... its faster and arguably more fun.

JetTest

Clutchless shifts, both up and down were no problem on my 620, and even smoother on my 696. My last reply I guess was not clear, my bad. I've seen several comments, both in another thread here as well as in the press about Ducati clutches requiring a lot of effort to pull. In my experience they do not seem that way to me. Also several comments about the reach to the levers being long. My hands are not that big, but the reach seems about perfect to me. First and second fingers hook right at the first knuckle, and that's pretty much all I ever use when I use the clutch. Because of that, I'm considering installing a set of short levers. Any experience with them? I agree, particularly on the highway or hard accell and decell, no clutch is more fun. On another topic, ever run with no mufflers, just the header? Was looking at my 696 exhaust one day, after the SS Termi's were installed, and thought the Y pipe on the header might look pretty clean without slip-ons. Pulled them off and started it. What a good sound! Drove around the neighborhood and kind of liked it. Neighbors probably would not care too much for it leaving for work in the mornings, but it's not nearly as bad as the cop up the street with the straight-piped Harley.

Alexandre

Quote from: JetTest on January 08, 2009, 04:05:09 PM
both in another thread here as well as in the press about Ducati clutches requiring a lot of effort to pull. In my experience they do not seem that way to me.

dry vs wet clutch... the dry clutch ducs do have harder pull