Clutch-less downshifting.

[onearmedbandit]

Due to the set-up on my bike, which while being quite good is now showing some shortcomings, hard front braking, blipping the throttle and clutching while downchanging is affecting my approach to corners, mainly on the hills where its twisty and a lot of accel and brake action. Gripping the brakes with two fingers, and using my thumb to flick the clutch and blipping the throttle means that the pressure I'm exerting on the brakes varies, upsetting the front end.

Now I'm trying to pratice steading my braking fingers, but my hands are not overly big so its stretching it already. So anyway, I resorted to a method I'd used before, but not on this bike, which is blipping the throttle the right amount, at the right time, and downshifting without the clutch. I can execute this with no drivetrain snatching or backlash, it enables me to steady the bike better for my entry making for a smoother faster corner.

So until I can come up with an alternative method for the clutch (I thought of many and been offered a few. Please, no one talk about puting the clutch where the rear brake is. Think about it, thats what I've told everyone who has suggested it.) I think, under harder riding conditions, I'll stick with this method.

Now, I have previously been told by a couple of people that it is not possible to execute a clutchless downshift without inflicting major damage to your gearbox, shortening its life dramatically. My arguement is that with no pressure on the box (from blipping the throttle) there should be no damage done, as releasing the pressure from the 'box is essentially what a clutch does. Sure, if you fuck up its not so good, but I seem to be able to nail it. With light pressure on the lever, the gear will 'fall' into place. I mean very light pressure. So, can anyone here offer a experienced opinion on this method, do you use it, any damage to your gearbox?

[moko]

I`m not technically gifted enough to figure out how but couldn`t you somehow integrate your clutch switch with your gear lever?Maybe even get something rigged-up like the old "heel and toe" gear levers so your heel operates the clutch while your toes operates the gears,that way with a bit of practice you could still do clutchless up-changes if you wanted to.I`m not sure about clutchless downchanges,sounds like a good way to lock your back wheel up if you get it wrong plus I`d have thought all kinds of strains on your transmission.

[What?]

I`m not technically gifted enough to figure out how but couldn`t you somehow integrate your clutch switch with your gear lever?
That has been done, I think by Triumph (definitely one of the pomgolian makes), late 50's. If set up parrallel to the bar-mounted clutch lever, it should work well.

[Motu]

The Triumph Slickshift,Jawa had it on several bikes and the Nzeta,and of course the Honda stepthroughs,I'm sure I've ridden other bikes with a gearlever/clutch combo but can't remember offhand.It'd be kinda hard to do it to a modern bike,it'd have to be external with cables...but not impossible,I'm sure someone has done/could do it.Lots of cars get set up for disabled drivers,various ways it's done to suit various disabilities - maybe a talk to the guys who do the conversions.

I see no problem with clutchless downshifting,it's done with dirt bikes all the time and I often do it on road bikes,it's just a matter of getting it right everytime.Bikes have a dog gearbox,same as crash boxes on trucks - I often drove without a clutch in the older slow reving slow shifting trucks,in fact some you couldn't even use the clutch...on the old Atkinson you could use the clutch for reverse and 1st,then the gearlever was in the middle of your leg,there was no way to use the clutch.

[**R1**]

hey bro, i shift down all the time without the clutch, it doesnt seem to be any harder on the box....i have been doing it for years and never trashed a box, also perhaps a slipper clutch would ease things up a little you can get them for most bikes....not sure on price tho???.....the only other thing i can think of is to use electronics the same as a quick shift where as you change dwn it cuts the engine for a fraction os a second to unload the box?? give me a call or pop over im sure we can think of something.

[vtec]

Hey, interesting issue. I had heard that motogp bikes (this could be wholly innaccurate) used a clutch that was incorporated with the gear lever so that it disengaged the clutch just before it changed gears, and I think I have seen a kit for road bikes which uses the same idea. I think you could possibly rig up one by yourself if you're clever. Also note that I only say possibly, cause I haven't looked at how much the clutch needs to move to disengage/re-engage. Good luck, tell us if you find a way to do it.

[dangerous]

OMB: I had a quick look at the KTM the dude in Chch races at Nelson port, and his clutch was facing down so he did a ralativle normal take off then rotated his hand so as he could brake the ususll way, that make sence.

[TwoSeven]

I dont blip and I use half clutch technique for changing gears (both up and down), I often go down multiple gears at a time and use the clutch to feel what the engine does.

There is no right or wrong technique, but one thing about clutchless shifting - it wont damage your clutch, but a bent gear selecter is fookin expensive :)

Last I heard some race bikes use a quick shifter triggered off the foot lever - but its normal for riders to use the clutch lever when more feel is required. The clutch isnt just used for changing gear - its important to also learn how to control the bike with it. :)

[Slingshot]

Here's a possible solution:

Hook up a solenoid to the end of the clutch cable with a small push button switch mounted in the top on the gear change pedal.

I'm not sure what force would be required to engage/dis-engage the clutch by you could probably measure that easy enough and just get a solenoid to match the force required.

When you put your foot on the gear pedal the clutch would engage, push down further to change the gear and as you lift your foot up off the pedal the clutch would disengage.

You could also rig up a second button on your clip-on, this would mean you could cut the clutch cable short and hide the solenoid contraption under the tank.

[Slingshot]

Just another thought...the push button and solenoid couldn't just operate in either all on or all off mode. Otherwise gear changes would be rather dangerous (wheelies all the time:no: )

If you could find a switch that measured the amount of pressure (maybe some form of a varible resistor) and a solenoid that would extend/retract a certain distance depending on the voltage it was receiving.

That would work, I'm sure of it.

[onearmedbandit]

Thanks for the ideas guys, keep them coming. Aaron, yeah I'll pop over when I get the chance, see what we can come up with.

[Rainbow Wizard]

No, not a typo. Makes sense to me to rig it up so that your jaw drives the clutch. Even though it would mean you'd need to link your helmet with a wire or flexible tube. There's well enough pressure able to be exerted in a controlled fashion by the jaw. You even have the choice of having it between your teeth and adding a flavour to the device. Sweet as shiftying here we come.

[StoneChucker]

I haven't read the replies, so apologies if this has been covered.

On http://www.ciamotorsports.com.au , under the '04 R1 section anyway, check your bikes manufacturer, they have clutchless powershifters. I'm not sure what they use, gas, or whatever, but that might solve your problem?

*EDIT* On the above site, under your bike:

MPS Sportbike Auto Air Shifter Complete Kit

MPS Sportbike Autoshift setup..! For FULL throttle... Clutchless shifting.... AUTOMATICALLY! Click on picture for details. This kit includes the shift chips, air compressor & horn wiring harness
$1,000.00

Thats the complete and full system, there are cheaper ones, and possibly different makes?

[pete376403]

Killing the ignition momentarily is enough to unload the gear dogs and allow a smooth shift to happen. A press button type kill switch would be enough. My dad told me he did this waaay back when, with a kill button on the magneto of his bikes. Possibly the origin of the term "button off" referrring to closing the throttle/slowing down (but not stoppng)
Or you could ride a Suzuki - they have buttery smooth gearboxes that let you get away with all sorts of abuse.

[Gixxer 4 ever]

So, can anyone here offer a experienced opinion on this method,
I do not race on the track so maybe this is a different situation but I ride a 97 GSX-R 750. I seldom use the clutch to change down. Most of my up changes are clutch less as well. When I need to change down, going in to or in a corner, I unload the box by dropping the revs a fraction. Now this works when you are running 6-8 k and over on the rev counter. As soon as the throttle drops 1k or so it just drops in as smooth as silk and you are back on the gas hard to drive around the corner. If you are just cruising below 5k then you some times need to us the clutch but most changes are silky smooth without.

[onearmedbandit]

Pete - I do ride a Suzuki, namely a 97 Gixxer 750.

I think I might continue with the clutchless downshift for the time being, works well enough so stick with the status quo. However, I will be seriously looking into the other setups mentioned here. always good to have something trick eh??


Next project is completely dropping the left clip-on, imagine the looks that would get!! Also stop any cretin from riding her away, not that they'd have much chance now. Its funny watching bi-armed people (like my brother who does my warrants) try and ride my bike even after I taught them. Seems to be too much for you 'normal' people to get around! Imagine a opportunist theif trying to work it out!! The gyroscopic effects from the front wheel should negate any weight/balance issues, shit how much does a clip-on with switchblock weigh anyway.

[Blakamin]

Next project is completely dropping the left clip-on, imagine the looks that would get!! Also stop any cretin from riding her away, not that they'd have much chance now. Its funny watching bi-armed people (like my brother who does my warrants) try and ride my bike even after I taught them. Seems to be too much for you 'normal' people to get around! Imagine a opportunist theif trying to work it out!! The gyroscopic effects from the front wheel should negate any weight/balance issues, shit how much does a clip-on with switchblock weigh anyway.
Shit hot!!!! that'll stop any thievin bar-stards... they wouldnt even be able to wheel it up the road!!!! :headbang:

[Slingshot]

Next project is completely dropping the left clip-on, imagine the looks that would get!! Also stop any cretin from riding her away, not that they'd have much chance now. Its funny watching bi-armed people (like my brother who does my warrants) try and ride my bike even after I taught them. Seems to be too much for you 'normal' people to get around! Imagine a opportunist theif trying to work it out!! The gyroscopic effects from the front wheel should negate any weight/balance issues, shit how much does a clip-on with switchblock weigh anyway.


You should leave the left clip-on on, just wrap razor wire around it....that would make you look like a real bad arse...:stoogie:...and if someone did try to pinch it they would instinctively grab for it :devil2:

[Motu]

We used to be able to ride the slickshift Triumphs with one arm,just ease up on the gearlever to take off,same as a car.I rode my C50 with a locked clutch like that for more than a couple of years,using my heal to release the clutch...but I only had one intersection going to work and half the time it was clear.

[cowpoos]

Try holding a small bit of throttle on...never letting it return to full off....no bliping...and wack the clutch in drop your gear...the revs will rise to meet the lower gear [as long as you don't spend a hour or so with the gear change]...and smooth as silk...it won't make f**k all difference to braking performance...feel very similar to riding two stroke with no engine braking.
Takes a few trys to get it right...but very easy to perfect...and becomes 2nd nature in no time to most people...if your've got money get a slipper clutch!

[What?]

The Triumph Slickshift....It'd be kinda hard to do it to a modern bike,it'd have to be external with cables...but not impossible...
Reckon you could do it by making a mirror-image of a brake pedal driving through a telescopic rod to a hydraulic master cylinder to operate the clutch, hooked via slot and pin to the gear lever, so clutching only works on down-shifts. This would be easiest to achieve by setting it up to have an up-side-down shift pattern.
Assuming that getting off the line using the hand lever is not a problem, this should fit the bill as clutch-less up-shifts shouldn't cause the box too may problems.

[scroter]

Hey, interesting issue. I had heard that motogp bikes (this could be wholly innaccurate) used a clutch that was incorporated with the gear lever so that it disengaged the clutch just before it changed gears,

well i seen live footage on tv of rossis fingers dancing on a clutch lever when changing down. im sure they have got one of those wide open switches the ones that kill the ignition for changing up tho. i dont think these would work for changing down unless you got the slipper clutch cause you need to blip the throttle to match engine speed with gear speed.

[TwoSeven]

Most of the cheaper units are only upshifters - dynojet and mps being examples. The fancy ones also allow downshifts as well and involves switching the engine off and a few other things.

Personally, i'd be happy with an upshifter, but I prefer doing manual downshifts with the clutch for better control.

As I said before, I dont blip and quite a few people I know dont, but then I know where my shift points are and I work the clutch more for feel and control - its just a different riding style. From my understanding blipping came out of california superbike school (probably a keith codism) and is taught in aus and they seem to think its gospel. Never seen it done anywhere else.

If you want to build a shifter, google all the existing systems and see how they do it. I dont think the electronics would be that difficult for the electronically minded.

[vifferman]

how much does a clip-on with switchblock weigh anyway.
By the way - do you use the lefthand switches (presumably low-high beam, indicator and horn)?

[vtec]

well i seen live footage on tv of rossis fingers dancing on a clutch lever when changing down. im sure they have got one of those wide open switches the ones that kill the ignition for changing up tho. i dont think these would work for changing down unless you got the slipper clutch cause you need to blip the throttle to match engine speed with gear speed.

Well I didn't mean all of them, but I think at least some of them run with a clutch trigger from the foot pedal, I think it's still debatable whether it's better than a normal clutch, I also think they run with a hand clutch as well to control launches. :mellow: Or like you say it could be an ignition kill system to save the gearbox for clutchless upshifting that was misconstrued to being a gearlever operated clutch and then conveyed to myself.

[onearmedbandit]

Twoseven - I 'blip' to match the engine speed to road speed, due to going down a gear.

Vifferman - I use the indicators currently by reaching 'cross the bars, not good I know but I'm still to convert the switch over to the left bar. Horn, nah thats what the 'loud' twister control is for, 'specially with a yoshi pipe! Highbeam, when necessary.

[What?]

well i seen live footage on tv of rossis fingers dancing on a clutch lever when changing down...
You forgot to mention that Rossi's gearbox only has to last about 45 minutes :crazy:

[mattt]

You forgot to mention that Rossi's gearbox only has to last about 45 minutes :crazy:

....and probably costs more than my zx9 :niceone:

[Madmax]

just on a different note
The old kawasaki H1/H2s
had a different gear box pattern
neutral down all gears up
(plus the shaft lets u reverse the pattern)
bloody handy when you break a clutch cable
just give it a push and whack it in gear off you go
you may be able to get a new selector made?
PM me may be able to get it done
(if not a mate may be able to do it myself) :unsure:

[alastabesta]

sorry to dig up this old post but after reading a few posts about shifting up/down with or without clutch, I'm still confused as to whether it does any harm to the gearbox... :confused:

[Waylander]

I`m not technically gifted enough to figure out how but couldn`t you somehow integrate your clutch switch with your gear lever?Maybe even get something rigged-up like the old "heel and toe" gear levers so your heel operates the clutch while your toes operates the gears,that way with a bit of practice you could still do clutchless up-changes if you wanted to.I`m not sure about clutchless downchanges,sounds like a good way to lock your back wheel up if you get it wrong plus I`d have thought all kinds of strains on your transmission.

Someone may have suggested this but I wanted to get it out before I forgot.
If you are ok with some heavy mods to your bike it should be posible to attach the heel-toe shifter mentioned above to activate the clutch no matter wich way you go. would require a pully set up though I think . no idea how you would be able to hold the cutch in on it to rev it up ready for wheelies or fast accel. Maybe keep your thumb clutch active aswell.

[That Guy]

Just read this - a slipper clutch; as found on race bikes, some ducatis etc, would help reduce any stress on the gear box by 'backwards' slipping on the downchange. Also you could fit an ignition cut out - race bikes have this for clutchless shifting - the moment the gear lever is engaged the ignition is momentarily cut (above a certain rev amount) to 'unload' the gearbox and allow the next gear to be selected with little effort.

[cliffy]

a slipper type clutch would probably be the way to go, from what i'm told their pretty good.
I have also seen a set up for some motards whereby they have a thumb operated lever on the throttle side ...... now I can't actually remember whether it was a brake or clutch lever but at the time i thought "hey cool". :niceone:
but i can't remember the website i saw it on :brick: but it was one i came across when i had don a search under motards or supermotards and i think they were a specialist supplier in the UK you could do a search for them if you liked(maybe a wild goose chase i know) but i will also see if i can find them again because if you saw the setup you may be able to hi-jack and or modify to suit. :spudwhat:

[TwoSeven]

The Triumph Slickshift,Jawa had it on several bikes and the Nzeta,and of course the Honda stepthroughs,I'm sure I've ridden other bikes with a gearlever/clutch combo but can't remember offhand.It'd be kinda hard to do it to a modern bike,it'd have to be external with cables...but not impossible,I'm sure someone has done/could do it.Lots of cars get set up for disabled drivers,various ways it's done to suit various disabilities - maybe a talk to the guys who do the conversions.

I see no problem with clutchless downshifting,it's done with dirt bikes all the time and I often do it on road bikes,it's just a matter of getting it right everytime.Bikes have a dog gearbox,same as crash boxes on trucks - I often drove without a clutch in the older slow reving slow shifting trucks,in fact some you couldn't even use the clutch...on the old Atkinson you could use the clutch for reverse and 1st,then the gearlever was in the middle of your leg,there was no way to use the clutch.


Might I suggest that your trying to do too much stuff that doesnt actually need to be done.

It sounds like to me you are over-braking, then gunning it up too fast again for the next bit.

I'd suggest that you try doing the circuit without using the brakes at all and just one or two gears - at first you'll go slow, but it will force you to take the right lines and work the throttle correctly.

I have a little game in that you go round your fave circuit at a comfortable pace. Every time you use the brakes (front or back) you score one point.

The object is score no points at a pace you are happy with. Once you achieve that, then you can think about using the brakes.

[bugjuice]

I reckon this (http://www.ciamotorsports.com.au/detail.asp?Ref=659&Model=Kawasaki%20ZX-636/600rr) is what you need. Mentioned a couple of times before, this is the clutchless system. I basically replaces the need for a clutch, but I'm guessing you'll still need a clutch to move from a standing start.

yeah, ok, this is for a kawa, but I'm sure it's for any bike..

[cliffy]

i'm pretty sure it was a thumb brake now, like doohan used in 92 at assen apparently (when he broke his ankle etc) but if you could mobify/make a thumb or finger operated hydraulic master cylinder(and there are plenty of small comp ones on the net) you may be able to run a small lever insideand slightly below, or above your brake lever (assuming that you may only use one or two fingers for braking anyway) and operate it with the spare fingers??or thumb??..........man i'd like to be involved with helpin you out on this, my head is spinning with ....maybe he could...or maybe this or that would work. :wacko:

[onearmedbandit]

Wow, another thread revived! All things are sorted now, got the clutchless downshifting sorted like its second nature. Sure sometimes I am hard on the brakes entering the odd corner, its all good as I like the feeling of the bike squirming underneath me and the chucking her on her ear and gassing up hard. And sometimes I prefer to ride smoother, and its probably just as fast, maybe even faster it just depends on my mood and who I'm riding with.

Now the next mission is to work out how to clutch-up second gear wheelies. I can power her up in 1st and go through the box, but I'd love to be able to bring her up in 2nd as they're easier to regulate. Flicking the clutch however requires me to release my grasp on the throttle momentarily and thats not a good situation to be in when attempting a mono.