Electronic quick shifter

chrisk

chrisk

Hero member
Location
Brisbane, Australia
OK, so, having explored some info on Quick Shifters I would like some input on the following.

On a SF750 gearbox, is a Quick Shifter going to a recipe for disaster?
Creates a clutchless shift up be means of a pressure switch, or micro switch, when lever is actuated in the gear up position. This cuts the power to one, or both, of the coils for 40 - 80 Milliseconds (variable to suit gear change speed) by a simple debounce-delay switch circuit (monostable)  .
Whatever that is: Thanks Drikko!

The next gear is selected without using: the clutch or backing off the throttle.

Down changing remains as per normal.

Sample here: http://www.youtube.com/watch?v=gVqkg5ApYpY

Question is: Will the gearbox handle it? No doubt the rev limiter be farting on each false neutral found.
 
Chris don't quote me on this but I expect the 3C gearbox is similar.I get a clash in the shifting mechanism on occasion,not noisy but the gear does not engage.Take a little pressure off the lever and continue and in it goes.I think the engagement is course in the older models.There not Harley bad but there is quite a long throw.No where near as many false neutrals as when I had the left crossover thankfully,there far from pleasant into a corner.Thats all I got,no idea how the dogs will react to this stuff.Did see some lofting of a foot and hard stomping to get 1st  with the revs high and the resultant horrible grinding done on a very very fast twin once,the look on the owners face wasn't happy.I think some sympathetic feet needed My bet would be more damage than time gained on the track,MAYBE.
 
The thing that concerns me is if the power gets switched back on before the dogs have fully engaged which I reckon will melt the gearbox, but I wouldn't know, just worries me!
 
drikko said:
,, which I reckon will melt the gearbox, ,,
Click to expand...
melt ??  reckon we can do better than that?

what about,  explode?  shatter?  ok,,  disintegrate !!  :-\ 

& i'll put money on the 4th-gear fragments smashing through the top of the case to improve the breathing a bit.
yea,  just guessing ay.  8)
 
The trick with all of these shifter systems is to have the ignition cut-out set to the shortest time possible while still unloading the drive train long enough to catch the next gear. With the two stroke race bikes I've worked on in the past this was relatively easy. New parts, better machining, better materials, and a relatively short and precise lever throw (not the usual slop that creeps in with our old dinosaurs with a few kilometers under the belt). A longer interruption leads to more banging and stress on the gears themselves. Even then the gears we used on the 250 Aprilias got thrown out after two race weekends. The TZ Yamahas and RS Hondas held up better but everything got checked every evening after practice or the race was over. 'Dunno if this is something you want to add into the regular maintenance plan for your SF.  :o

Tom
 
He won't need to pull anything apart as it will automatically provide its own inspection windows, and some parts will auto eject for easier inspection and maintainence.  :LOL:
 
Flick the throttle closed to unload the dogs as you simultaneously change up without using the clutch that's all I do when pressing on, no need for any electronics just use your brain to co-ordinate everything.


  Keith
 
couldnt agree more with Keith, I have been doing that for years and sometimes even do it because of weariness, up changes are a breaze, and also give the satisfaction that everything is right with the bike and with the riding and the rider, all coming together, in one flowing sweep of performance, so to speak,down changes can work as well, very handy if you have your left arm out for a turn off the main road, and you want the idiot behind to be clear what you are doing.I once set off from a French rally on TOG, with my left hand swollen like is was full of compressed air,(gout) and not able to operate the clutch more than once.I used the clutch to get going or (sometimes) to stop, no more than 10 times in a 500 mile ride, I could have made it back without even a clutch lever fitted if I had been forced.

And anyway, I dont want anything added that might not work when I want it to, create a maintenace issue, cost me money,break down, and not get me anywhere any better or quicker.
CLEM
 
laverdakeith said:
Flick the throttle closed to unload the dogs as you simultaneously change up without using the clutch that's all I do when pressing on, no need for any electronics just use your brain to co-ordinate everything.


  Keith
Click to expand...

Thanks for the input, all relevant points.

OK, so we dump the 'debounce-delay switch circuit (monostable)' idea. For fear of mumbo coming back on before everything is engaged.

Thought 2: If the internal gear selector is fitted with two magnetic reed switches (the magnet mounted on the selector arm, the reeds on the casing), one 'just' off home (shut power off) and one all the way home (power back on) wouldn't that ensure that the motor is shut off in the case of a miss engagement, rather than relying on A: a timer or B: my monounstable brain?

As I understand it, the selector doesn't complete it's travel until the next gear is fully engaged (correct me if I'm wrong), in this case, that's when the mumbo comes back on.

A switch on the dash could be used to ignore the reed switches for pits, start grid etc.

We use the same pricipal on our machines at work. Eg: If the second reed is not made, and the next phase of operation is not.

Edit: It may be too early in the morning for my monounstable brain to work .......... I'm off to the gym to think about it some more.
 
My triple with the lightened crank revs up faster than I can work the clutch on up-changes during track sessions.  Clutch-less changes are now the norm, works very well with my CR box.  Can imagine a stock ratio box would require bit more sympathy to avoid clunky changes. 

Lever travel on the 750 can be reduced by using triple bits for the gearchange mechanism, including the selector drum inside the box.  Helps improve gearchange action a bit.

piet
 
Chrisk, you are talking bollocks
heer we are dealing with underpowered, air cooled,top heavy, 40 year old technolodgy bikes, go and buy a Desmosedici
CLEM
 
CLEMTOG said:
Chrisk, you are talking bollocks
heer we are dealing with underpowered, air cooled,top heavy, 40 year old technolodgy bikes, go and buy a Desmosedici
CLEM
Click to expand...

ill see that and ill raise you two turbos and a thumb switch rear  brake
 
It will work fine.
A forerunner of patent quickshifters was rewiring the horn button to act as a kill switch, used for full throttle gear changes. It was a cheat trick on proddie bikes in Oz. That was way back in the day before bikes were digital, too.
 
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