Gear Shift Assist notchy?

As I’m sure you know, a motorcycle gearbox is constant mesh, no synchromesh or baulk rings etc.

All of us have been doing clutchless up shifts for years, you roll off momentarily which unloads the ‘box and allows you to lift the selector and effectively crash the next gear. Because there are only dogs to engage it doesn’t sound or feel bad

So logically a down change should work the same, the ratios are no different and the gears are already in mesh

The problem is that you would need to blip the throttle to unload the ‘box and to match revs as you crash the next gear down at exactly the right moment and just long enough so as not to re-accelerate as you shift

You almost certainly can’t do that with your throttle hand which is why you don’t do clutchless downshifts, but a quickshifter can :thumb2


Yeah I know, but the question still remains, do bikes with an auto blipper for downshifts also need a slipper clutch? Are there any modern bikes that have an auto blipper without having a slipper clutch?
 
I don't suppose it needs a slipper clutch. I view the slipper clutch as a rider aid for when someone screws up a downchange - no blip, just closed throttle and dump the clutch. That would probably lock the back wheel.
 
2018 GSA 1200 has a slipper clutch. Well BMW call it “Multiplate oil-bath, anti hopping”
 
2018 GSA 1200 has a slipper clutch. Well BMW call it “Multiplate oil-bath, anti hopping”

I know that and had it doing its stuff once. I just question whether a quick-down-shifter *needs* one tow work or if it's there as a comforter for the hamfisted/hamfooted among us on our magnificent steeds, especially if we have SWMBO perched on the pillion position.
 
Yeah I know, but the question still remains, do bikes with an auto blipper for downshifts also need a slipper clutch? Are there any modern bikes that have an auto blipper without having a slipper clutch?

From my own experience with my 899, no it doesn't. For shifting down I'd quite often rest my foot on the selector and then when I was on the brakes just give the throttle a quick blip and it would slot into the lower gear without using the clutch. You could get a series of quick downshifts without ever using the clutch and the back wheel never locked up either. :) There were also those on forums and things who bought blippers for them and never had any issues. Hope that vaguely helps answer whether it's possible to do without a slipper.
 
From my own experience with my 899, no it doesn't. For shifting down I'd quite often rest my foot on the selector and then when I was on the brakes just give the throttle a quick blip and it would slot into the lower gear without using the clutch. You could get a series of quick downshifts without ever using the clutch and the back wheel never locked up either. :) There were also those on forums and things who bought blippers for them and never had any issues. Hope that vaguely helps answer whether it's possible to do without a slipper.

Dare I say it, but the Ducati 899 isn't a fair comparison.

Because yes it doesn't have a slipper clutch...

BUT it also uses an advanced engine braking system to reduce the back torque to the rear wheel.... negating the need for a slipper clutch.

So that particular bike isn't a good comparison.
 
Dare I say it, but the Ducati 899 isn't a fair comparison.

Because yes it doesn't have a slipper clutch...

BUT it also uses an advanced engine braking system to reduce the back torque to the rear wheel.... negating the need for a slipper clutch.

So that particular bike isn't a good comparison.

The engine braking control (EBC) would most definitely not stop the rear locking up if you downshifted one too many gears, I can assure you. So I'd say it is a fairly decent comparison. The EBC just limited the effect of the engine braking for corner entry and control by leaving the butterflies open a certain amount.
 
I'd have a guess though....

The cam speed sensor sends a signal to the ECU which identifies when the pistons are at the correct position for spark ignition.

If the cam speed sensor is not correctly aligned, and the cams are out of alignment, the quickshifter won't be in sync either...

So when you change gear, the quickshifter tells the ignition to cut the ignition spark as it's about to change gear... the cam sensor may not be sending the correct position information at exactly the same time....

So the quickshifter might be telling the ECU to cut a spark that isn't there for another millisecond later..... as it's all out of alignment.

This means the engine is still under load (partly), hence the resistance, clucky, crunching crap going on.

Quickshifters work on milliseconds, so it appears to make a difference and needs to be in alignment with the cam position sensors and (obviously) the correct cam alignment.

The better everything is in alignment, the sweeter your quickshifter is...

That's my final answer...... :D

You sure its not the gearbox thats still under load ? Just saying :comfort:augie:green gri:D
 
That is silky smooth, I have exactly the same bike except I don't use the quick shifter as it's too harsh on the gearing!
 
I was chatting to Tall Lad on our group rideout yesterday and I asked him how his bike was after we did his Valve Check and Cam Alignment adjustment.

Great, he said. Then commented how smooth his Gear Shift Assist (quickshifter) was up and down the gearchanges, since we adjusted the cam alignment. Before we did the work it was notchy and harsh at times. He loves how its so smooth and easy to use now.

I concurred as mine is super smooth as well.

So I just thought I'd mention our findings on here, if your gear shift assist is unpleasant, notchy, grinding, harsh, bumpy, stiff..... and not super smooth..... it could be your cam alignment needs redoing.

:D

Could you please provide more info about cam alignment? What tools do you need?
Thanks
 
Could you please provide more info about cam alignment? What tools do you need?
Thanks

You'll have to re-read his and others posts on the subject - Warlord flounced yesterday. For now...
 


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