Gear Shift Assist notchy?

From what I’ve read as many people are finding the trigger to be mis aligned, occasionally by a fair bit. That may compound the timing issue if it’s all out of alignment.
 
Engineer said:
How does the auto blipper really work, the engine must be disconnected from gear box in order for the revs to be instantly raised - I assume that the slipper clutch is just forced to slip.??? It just doesn’t feel right on my bike other than occasionally when slowing rapidly under brakes and down changing, but it all seems a bit crude so I don’t bother using it and continue to manually blip using the clutch.
Click to expand...

No the back torque limiter isn't affected. It happens really quickly.

As the engine cuts ignition, it unloads the gearbox momentarily to allow you to shift gear. this 'moment' is called the kill time. Kill time is pre-programmed to be a certain value (like 60 milliseconds) which is enough time to complete the gear change and then reload the gearbox as ignition restarts.

It's very fast.
 
Just have to remember it isn't designed to be an automatic gearbox.

It's designed to allow very fast gear changes for race circuits, and fun factor.
 
spoonz said:
From what I’ve read as many people are finding the trigger to be mis aligned, occasionally by a fair bit. That may compound the timing issue if it’s all out of alignment.
Click to expand...

Have you altered your trigger position from factory settings?
 
Warlord said:
No the back torque limiter isn't affected. It happens really quickly.

As the engine cuts ignition, it unloads the gearbox momentarily to allow you to shift gear. this 'moment' is called the kill time. Kill time is pre-programmed to be a certain value (like 60 milliseconds) which is enough time to complete the gear change and then reload the gearbox as ignition restarts.

It's very fast.
Click to expand...

But if the throttle is fully closed whilst rapidly slowing then cutting the ignition is going to do nothing, what you need to do is add a bit of throttle to unload the gearbox, yes cutting the ignition on up changes makes sense but not down changes.
 
Warlord said:
Have you altered your trigger position from factory settings?
Click to expand...

Nope, I just found a post by a guy in the US who documented all of the wet heads he timed. Out of 6, 4 were out on both sides and 1 on one side, the other was fine. 4 of them also had mis aligned triggers, and not always the ones with cam timing out.

No mention by them of shift assist related differences but smoother idle and less vibes etc. But it’s pos they just did not make a connection re shift assist and timing.
 
Engineer said:
How does the auto blipper really work, the engine must be disconnected from gear box in order for the revs to be instantly raised - I assume that the slipper clutch is just forced to slip.??? It just doesn’t feel right on my bike other than occasionally when slowing rapidly under brakes and down changing, but it all seems a bit crude so I don’t bother using it and continue to manually blip using the clutch.
Click to expand...

When shifting you slide the dogs back and forth between the different gears, and one gear has to be released prior to engaging the next one. The quickshift use this gap to either drop rpm (by chopping ignition) for upshifts or blip rpm (increase) for downshift.
 
spoonz said:
Nope, I just found a post by a guy in the US who documented all of the wet heads he timed. Out of 6, 4 were out on both sides and 1 on one side, the other was fine. 4 of them also had mis aligned triggers, and not always the ones with cam timing out.

No mention by them of shift assist related differences but smoother idle and less vibes etc. But it’s pos they just did not make a connection re shift assist and timing.
Click to expand...

Ok thats good, factory standard will help us see what you think after cam alignment.

I'm not going to dismiss autogs 'emperors new clothes' comment because I've only done two bikes... but we've both noticed a big improvement straight away after the work, and it seemed to coincidental
 
knutk said:
When shifting you slide the dogs back and forth between the different gears, and one gear has to be released prior to engaging the next one. The quickshift use this gap to either drop rpm (by chopping ignition) for upshifts or blip rpm (increase) for downshift.
Click to expand...

But if the timing is out, it won't be blipping enough on downshifts and it'll be crunchy
 
knutk said:
When shifting you slide the dogs back and forth between the different gears, and one gear has to be released prior to engaging the next one. The quickshift use this gap to either drop rpm (by chopping ignition) for upshifts or blip rpm (increase) for downshift.
Click to expand...

That makes sense to me, but as the lower gear goes in on downshifts the engine revs must rise instantly, which is not possible surely because of the engine inertia? - this would mean the back wheel would ‘skip’ unless the slipper clutch slips???
 
Engineer said:
That makes sense to me, but as the lower gear goes in on downshifts the engine revs must rise instantly, which is not possible surely because of the engine inertia? - this would mean the back wheel would ‘skip’ unless the slipper clutch slips???
Click to expand...

The engine blips to match engine RPM to gearbox RPM.... So it's perfectly matched.
 
Warlord said:
The engine blips to match engine RPM to gearbox RPM.... So it's perfectly matched.
Click to expand...

That’s the bit I don’t get because the engine and gearbox are only ‘disconnected’ be for a minuscule period of time as the dogs slide - the revs surely cannot rise sufficiently in that period of time? Do any bikes have an auto-blipper and no slipper clutch?
 
Engineer said:
That’s the bit I don’t get because the engine and gearbox are only ‘disconnected’ be for a minuscule period of time as the dogs slide - the revs surely cannot rise sufficiently in that period of time? Do any bikes have an auto-blipper and no slipper clutch?
Click to expand...

Ok, you could be right because my Triumph 675R had no slipper clutch... but the quickshifter only went UP the box not down.

So the Auto-blipper quickshifters have only been mainstream for the past few years... as slipper clutches have been as well.

Never linked the two before... maybe thats the reason.
 
Warlord said:
Ok, you could be right because my Triumph 675R had no slipper clutch... but the quickshifter only went UP the box not down.

So the Auto-blipper quickshifters have only been mainstream for the past few years... as slipper clutches have been as well.

Never linked the two before... maybe thats the reason.
Click to expand...

I am going to stick my neck out here and say that for downshifts an auto blipper only works if you also have a slipper clutch :)

I am happy to be corrected if there is a bike on the market with an auto-blipper for downshifts and no slipper clutch, but I cannot see how the revs could rise fast enough :)
 
Engineer said:
I am going to stick my neck out here and say that for downshifts an auto blipper only works if you also have a slipper clutch :)

I am happy to be corrected if there is a bike on the market with an auto-blipper for downshifts and no slipper clutch, but I cannot see how the revs could rise fast enough :)
Click to expand...

Does the S1000R/RR/XR have slipper clutch now? At least there used to kits for retrofitting slipper clutch on these bikes.

As these bikes are inline-4s, the blip will probably react for a much quicker increase in RPM.


I honestly am not sure if the slipper clutch is a factor when downshifting, but it does sound reasonable on twins with longer stroke.
 
Engineer said:
That’s the bit I don’t get because the engine and gearbox are only ‘disconnected’ be for a minuscule period of time as the dogs slide - the revs surely cannot rise sufficiently in that period of time? Do any bikes have an auto-blipper and no slipper clutch?
Click to expand...

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
 
I know it's not a motorcycle, but in a car you can do upshifts and downshifts without using the clutch.

One of my mates was racing his street car at Santa Pod years ago and his clutch cable snapped.

So I jumped in with the engine off, selected first.... turned the engine over and lurched away...... :D

Then drove it 150 miles home, planning my space ahead of the car, slipping it into neutral occasionally at slower speeds (providing you don't fall below 3mph it'll slip back into 1st). Using throttle to match gearbox and engine speeds, up and down the box (having the benefit of neutral to rev the engine for a lower gear change).

No problem. Got it home safe and sound..... :D
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
You must log in or register to reply here.

Similar threads

Shift Assist Pro!
Replies
6
Views
443
MojoMark
So what is it about 3rd gear?
2
Replies
21
Views
4,314
Mr Bean
Mr Bean
S1000XR / gen 1 vs gen 2
Replies
17
Views
4,330
Boxerlust
Gear Shift Assist Pro
3 4 5
Replies
85
Views
20,488
Rockred
Rockred
Tuckshop
eBike build here is my story
Replies
15
Views
2,359
Tuckshop
Tuckshop


Back
Top Bottom