Author Topic: The pro's and contra's of clutchless shifting  (Read 756 times)

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Offline Deltarider

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The pro's and contra's of clutchless shifting
« on: December 23, 2023, 12:13:42 PM »
Anything against clutchless shifting using spark cut technology? I mean what are the disadvantages and if there aren't, what is keeping us?
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Offline rotortiller

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Re: The pro's and contra's of clutchless shifting
« Reply #1 on: December 23, 2023, 12:37:05 PM »
With a quick shifter down shifting can still cause xmission damage and not sure if the clunky CB old gearbox would even see a benefit. Let us know if you do it and if it works out. If you gear down with the ignition off and turn it back on it will fill the exhaust like an afterburner lol.

Offline jgger

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Re: The pro's and contra's of clutchless shifting
« Reply #2 on: December 23, 2023, 01:42:28 PM »
I think up shifting with at least a slight back off of throttle is the easiest clutchless shifting. Did that for years of desert off road racing without issue, but always ( well most of the time) used the clutch for down shifts. It was a smaller bike with less H.P. though. Being a constant mesh transmission the abuse would probably be either the dogs of shift forks. Of course if a dog were to snap off, then all bets are off.

Personally I don't think I would do it for a street ride. If you are too weak to pull the clutch, then get a Burgman or something like that.
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Offline Tracksnblades1

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Re: The pro's and contra's of clutchless shifting
« Reply #3 on: December 23, 2023, 01:50:25 PM »
I think everyone has done it “accidentally” and “purposely”….😜
If you want to do it. I’d do it…we are not getting any younger..

Racers of all types accept the reduced component life…I personally don’t see a need for it (benefit), as I ride…
Some MX dirt bike racers routinely use that technique. Some are provided new bikes annually or sooner.
A good technique will probably determine your success (and your trans). I’ve seen it employed in deep loose sand with disastrous results.
.
Off road, I ride the holy grail. A 2001 CR500R with my son and his friends. This old bike still easily exceeds all my abilities.
I’m old and in the keep it all original and running mode. I wouldn’t risk damaging the trans and trying to source parts with greater wear. Besides most aren’t but a 1/3 of a throttle away and I still like rubbing their back tire, just to let them know exactly where I’m at…🤪

Even a QA50 has a mechanical internal clutch release mechanism activated by the foot shifter..
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Offline HondaMan

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Re: The pro's and contra's of clutchless shifting
« Reply #4 on: December 23, 2023, 07:26:37 PM »
The only 750 gears (C2) that I have seen with broken dogs on them, that broke while the engine was being used, came from drag bikes with the sprak-interrupter shifter.
The 500 seems to be much less hard on the gears in that regard. I knew many riders back in its day who barely used the clutch after the bike was moving.

I'm not sure about the 550-style gearboxes, haven't seen any broken ones of those at all. They have superior oiling and support inside the cases.
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Offline seanbarney41

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Re: The pro's and contra's of clutchless shifting
« Reply #5 on: December 23, 2023, 08:38:02 PM »
I shifted clutchless a lot on my first cb750, just because I could and was lazy and it was fun when you got it right...but once in a while you are gonna get it wrong and I understand thats how dogs really can get worn and rounded.  That engine got so it would pop out of 2nd and 4th if you did not shift it very deliberately, after many thousands of miles.

I don't know anything about using spark cut technology except this a basic drag race set air shifter set up?
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Offline PeWe

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Re: The pro's and contra's of clutchless shifting
« Reply #6 on: December 23, 2023, 08:46:53 PM »
Up shifting possible on a CB750 with a quick small throttle off.
That happen during quick shifting anyway.

My K6 had extra stiff clutch, cable needed lubrication. It has Barnett CB500 springs that are harder. So it happened my clutch hand got tired.
It has recently got dog leg type clutch lever for easier clutch.

Down shift not that good. Have done that when clutch cable has given up.

Important to feel eventual clonking or scratching inside, respect that and shift with more care. Undercutted 2-4 gears need respect for the mechanical when shifting.
« Last Edit: December 24, 2023, 01:32:44 AM by PeWe »
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Offline Deltarider

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Re: The pro's and contra's of clutchless shifting
« Reply #7 on: December 24, 2023, 02:16:00 AM »
I myself have practised upshifting without the clutch for a wile. The trick was to apply a little force on the shift lever just before you closed the throttle. Although there were no issues, I have stopped doing it. I have not practised clutchless down shifting.
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Offline bryanj

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Re: The pro's and contra's of clutchless shifting
« Reply #8 on: December 24, 2023, 02:34:13 AM »
500 does ok but the centre selector takes a beating, it was a 350 twin part and is well known to wear badly plus is now unobtainium except for an iralian firm making them to order for about $ 250 plus tax and shipping
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Offline Nurse Julie

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Re: The pro's and contra's of clutchless shifting
« Reply #9 on: December 24, 2023, 05:50:55 AM »
400/4 are great for clutchless up shifting, I would ride for miles and miles doing that as I was to lazy to pull the clutch in and my clutch was super light 😂😂😂. Never tried it down shifting though.
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Offline MauiK3

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Re: The pro's and contra's of clutchless shifting
« Reply #10 on: December 24, 2023, 06:56:19 AM »
I've upshifted that way but not down. I'm thinking that with my conservative riding it's not necessary.
Racing? maybe it would be a good thing to do.
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Offline rotortiller

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Re: The pro's and contra's of clutchless shifting
« Reply #11 on: December 24, 2023, 07:15:26 AM »
Quote
clutchless shifting using spark cut technology

Typically the throttle is held wide open while you go through the gears and the shifter sensor kills ignition etc  from applied foot pressure thus offloading the xmission some. There is a big difference between manual clutchless-throttle-matched low stress shifting and the quick shifter strain potential on a gearbox. Any monkey can up shift a constant mesh motorcycle without a clutch by backing off on engine torque. The quickshifter removes the need for any wrist action up shifting on the track. Some have an automated throttle blip feature to aid down shifts. Foot pressure activation, pressure direction (up or down shift pattern) ignition off time and blip etc are adjustable in many units but they work with the ecu or coil packs to cut fuel flow or spark. Some even damp fuel on to reduce spike.  Other thing is a slipper clutch keeps the rear wheel tame with the pavement. Old POS sohc is a wasted effort of time and money, save your money for unde-rglow lol.

Offline grcamna2

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Re: The pro's and contra's of clutchless shifting
« Reply #12 on: December 24, 2023, 11:05:17 PM »
I like using the clutch all the time,until i break a clutch cable,then I upshift the way described by just backing off a little a split second before each shift,carefully..
I down shift very deliberately by blipping the throttle 'in time'..
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