Shifting

[BC61]

You are talking about matching the engine speed to the wheel speed.
That's the purpose of blipping the throttle during down shifting.

I am talking about matching the the DRIVE gears speed in the tranny to the DRIVEN gears speed in the tranny. (and also unloading the tranny, while we are at it)
They are the same speed for the same gear. Only variance you will get is the lash between the gears, not a change in speed. This will change the load but won't help you control the engine speed at all when you go to a lower gear.

So, are we describing the same thing but still not answering your question?
Not really, you are describing a change in load between drive/driven gears enabling you to down shift. Not really necessary to down shift, as the motor decelerates below it's power band it's pretty easy to click a lower gear without any throttle change.

Maintaining control of rear wheel during down shifts requires managing engine speed between different gears. There has to be some disengagement between the rear wheel and the engine to blip the throttle. This disengagement comes from using the clutch or passing through neutral which doesn't happen on a sequential gearbox.

I've been teaching at racing schools for ten years and blipping the throttle has always meant matching engine speed to wheel speed. Maybe some just have a different concept of blipping.

All I was asking originaly was how do you blip the throttle without the clutch?

[Decreasing_Dave]

4 pages of confusing logic.......and you wonder why I fan the clutch??

This "blip'in" post has been beat to death! ;D

[Super Dave]

How are you blipping without the clutch? You don't pass through nuetral on a sequential gearbox so when do you blip?

Like Hitchthingie said, you just kind of unloaded it with an immediate simultaneous blip/downshift.  MC transmissions are not too complicated.  It can be done.  It was something that I had to work on to learn how to do it, but I can always revert to it.  It does work.  I was doing this in 1993 on a CBR600F2.  I raced nine races a weekend, taught my school, and then traveled to all the AMA national rounds riding 750 and 600 Supersport.  The bike was just used a whole lot.  Even got endurance raced.  The transmissions were just a bit soft on the F2's.  I have never had transmission problems on any bike I've raced either.  And that includes the priceless vintage bikes that I've been asked to race.

Was it counter productive to blip and not use a clutch?  Where I was doing it, no.  It was the easiest transition for the problem.  The blip allowed for a minor change in load that allowed me to downshift without the clutch.    I can't say that everyone can do it, but I'm not so unique that I can do something others can't.  That's what I teach.

As for using the clutch on upshifts, the clutch has to slip.  Wear on the clutch, clutch material, heat.  That never seemed very good to me, and I have yet to have problems related to this.

And all of this just because I said that I can downshift without a clutch...  
 ;D

[BC61]

And all of this just because I said that I can downshift without a clutch...

All I wanted to know is how you blipped the throttle without the clutch but a few others jumped in with theory of thier own.

Your answer pretty much summed up what I was looking for, you don't 'blip' the throttle, as understood buy the general racing public to be matching engine speed to rear wheel speed, but merely change load on the tranny to make a shift. This probably took place mid corner or in transition from one corner to another where slight throttle modulation is all that was needed to make the gear change. I doubt you did this under hard straight line braking with multiple gear changes in a short distance.

I guess people have a difference in the meaning of things.

[Super Dave]

I doubt you did this under hard straight line braking with multiple gear changes in a short distance.

You're assuming I did not.  

I did.  After about the first race at Heartland Park where I began working on it, I started doing it everywhere.  

Like I stated early on in this thread, I only used the clutch at the start, then did clutchless downshifts the whole time during racing, period.  Sure, I guess coming into the pits I used the clutch, but that was no problem.

[BC61]

Fair enough, not challanging your method really only wanted to know what you meant by 'blip' the throttle.
Guess it's just a difference in terminology, I always understood a blip as a significant spike in throttle application.

[Super Dave]

That's exactly what it was.

Even when downshifting and blipping and clutching, everything has to mesh again;  there is a little bit of mushiness to the sound when eveything gets together. Without the clutch, it still sounded the same, but a little more crisp.  Similar to how a clutchless upshift sounds when compared to a clutched upshift.

Unlike downshifting with the clutch and no blipping where you really hear the rear wheel pull up the rev's of the engine when the clutch is brought out.  

[tcchin]

Never said full throttle cluchtless shifting was best technique but it is do able and does have it's place.

Not really, you are describing a change in load between drive/driven gears enabling you to down shift. Not really necessary to down shift, as the motor decelerates below it's power band it's pretty easy to click a lower gear without any throttle change.

Not to rock the boat now that everyone has calmed down, but I feel compelled to express serious doubt about the validity of these statements. Rather than comment on this yesterday when it would have been more timely, I decided to go home and try this on a few different bikes. The results were absolutely consistent: Not a single bike could be shifted either up or down on either steady or trailing throttle. Sure, I could have tried to stomp on the shift lever with more than normal shifting force, but that would have only damaged my shift forks. The only way I could effect a clutchless gear change was by blipping the throttle while applying pressure to the shift lever.

blip: noun - A transient sharp movement up or down (as of a quantity commonly shown on a graph).

BTW, why is the powerband relevant while the bike is decelerating on trailing throttle?

[Super Dave]

I know that some small bore two stroke MX bikes can do full throttle upshifts.  But there is less HP and torque there.

Only thing I can add.

[handicapped_raceer]

I fan the clutch on upshifts.  I've used this method before on some street drags and it works well.  You don't have to let off of the throttle at all.  You just pre-load the shifter and grab a little lever 'til it shifts.

It worked off the grid at Firebird everytime. ;D ;D

and if you pre load the shifter you will be re-building you transmission :o so do that boys and girls

[DRU2]

Why would a false nutral be created when down shifting? Mech problems lack of concintration?The bike does not slip out of gear on acceleration only coming into the corners sometime. ???

[Super Dave]

Um, I don't have a technical answer...  But you're not under a high HP load when de-accelerating to make the trans dogs really pull themselves together.  So, you could just slip it right in between.  Then there is that clutch softening everything together.  

I never had false neutrals on clutchless down shifts.  But I probably won't do that much again on this new bike.  Maybe I should....?