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Clutchless change advise

Discussion in 'New Riders and Riding Tips' at netrider.net.au started by Leakey, Feb 11, 2008.

  1. Thanks to whoever explained (in one of the threads in here) about how to change gears without the clutch, while accelerating.

    I got it down pat today, and felt like I was Stoner. Then I realised I wasn't, but it was a great 3 seconds.

  2. Yeah, and you'll feel like rossi when his bike sized one tournement.
    Unless you have a quickshifter fitted, I would advise against doing this other than when required (clutch problems).
    You strain the shiite out of the gear box as well.
  3. Gotcha. Figured it wasn't a good habit to get into, but learning something new always gets the adrenaline pumping.
  4. What an Absolute Load of Bollocks!!!

    If you get used to it, you can shift with less strain on your gearbox.
    PP How about you check your facts before you state things so catagoricly.
  5. Hmm....there is controversial evidence on both sides whether or not it damages. Consensus from most people, is that its fine on upshits if you do it right, but the majority of people cant do it right on a downshift and can damage it then.

    PP, you also realise that those quickshifters just cut ignition for about 100ms, so the gearbox isn't loaded, and are designed for full throttle shifts?

    IMO, based on no particular research, the wear caused to the gearbox is there, but isn't highly significant, unless there is load on the engine. Basically the gearbox will slow down the input shaft fairly easily if the throttle is closed (or partly closed) because thats the state that the engine prefers to be in for that amount of throttle. If all the engine is doing is compressing air and burning little fuel, it has less resistence to the revs dropping, because ideally without fuel burning the engine doesnt want to turn.

    What Im trying to say is like this situation; you are catching a cricket ball, if you stick your arm out and hold it in spot, its going to hurt your hand a bit, but if you let your hand move backwards with the momentum of the ball, you will still catch it, but your hand won't hurt. So when you force it into gear without closing the throttle a little, your catching a ball with a rigid arm. When you close the throttle a bit, you are letting your arm fall back with the ball. Theres a chance for you to break a bone in your hand either way, but extremely unlikely if you let your hand fall back.

    PS your gearbox still gets worn a little when you change with the clutch, because the synchros still have to slow down the input shaft.

    PPS, if someone says "use the clutch thats what its there for" technically the clutch is there for a situation where you don't want the engine to match revs, which is when you are stopped. If you can rev match perfectly, dog engagements won't get worn at all.

    PPPS, I have known some people that drag all the time, and clutchless shift and don't have box problems.
  6. a poor shift is a poor shift - doesn't matter if you are using the clutch or not.

    Doing it under power and getting it wrong accelerates the process a bit, but everytime you get the big clunks you aren't doing it right, clutch or not. For the non believers, go and ride pillion with a rider who knows what he's doing - he can put his left hand on your knee and go up through the box without you being able to feel it.

    WHen you can get to that level, come back and tell me that it is bad for the box.
  7. Rubbish PP.

    A quickshifter does the same thing as what you can do with a slight twitch from your throttle hand, albeit more consistently, saving time not your gearbox.
  8. I am jumping on the total BS bandwagon too. You'll NEVER damage a clutch doung clutchless shifts, the clutch isn't doing anything except transmitting power. It's locked up when you clutchles shift. You'll damage teh clutch more downshifting and feathering teh clutch.
    If you do it REALLY incorrectly, you may eventually wear out shift forks or dog clutches, but by the time you got to that stage, I'd hope you would have the technique well and truly sorted out!
    I never use teh clutch once the bike is moving, unless I am coming to a stop, or for the 1-2 up/downshift if the surface is slippery, or it is raining. I'll also use it if stopping in a big hurry.
    Yes, I clutchless downshift, becuase I can. If it was going to damage a bike, it would have damaged my 270kg shaft drive bike, with 92k kms on it. I have been clutchles shifting it for oh, 15k kms at least.

    Regards, Andrew.
  9. Personaly I have found once I got them sorted out clutchless downshifts are even smoother than upshifts. But get your upshifts sorted before you start playing with the downshift.
  10. PP, are you actually as obtuse as you seem to be regarding motorcycle topics/technology or were you just trolling in this instance? :-k

    If you're seeding threads with stupid responses, then seriously, save it. The right heads would respond correctly anyway, without any of the aggro you seem to engender.

    I think in future, the SOP response for PP would be, "Please explain why that's so". If you're making genuine statements, I would LOVE to see how you justify them.
  11. Huh?...Buggering up a clutchless shift is'nt all that good for the gearbox, I agree, but if it's done properly, it is'nt THAT bad. I would agree that if the technique is perfected it has marginally increased wear compared to using the clutch, when up shifting.

    Downshifting could require some additional perfection of the techinque because of it's nature, but again, when done properly, it won't cause excessive strain.

    Personally...I do both up and down, with and without the clutch depending on what I'm doing at the time. Has'nt ruined anything in the 11 bikes I've owned/ridden on and off over the past 35 yrs or so.

    The quickshifters don't do anything that a deft right hand can't do, but would be more beneficial in a racing environment.
  12. say wot?
  13. The clutch doesn't stop cogs spinning, it does exactly the same thing as a brief stutter on the throttle, removes load from the drive train. A quick clutchless and clutched shift are so close to being the same thing it's a waste of time discussing "damage".
  14. Clutchless upshifts are better for everything if you are at high revs, ie. on a racetrack
  15. I used to think this, but as i have goten better at them i am now doing low rev clutchless shifts with no surgine at all from the bike and with the shits being silent (No Clunk at all) it is just about getting it ballanced well and there is no loading at all.
    It is SWEET
  16. Yeah, so it should be, mate. Bike gearboxes are constant mesh. The telemetry on Doohans NSR500 showed that he upshifted at 95% throttle. Back in the olden days, when I was racing, everyone, prettymuch, used to keep the throttle pinned, with weight on the shifter, and the box would shift when the rev limiter cut in. Made for quicker laptimes but selector forks needed replacing from time to time. I always clutch backshifts, but these fancy slipper clutches weren't around then.
  17. All gearboxes now are constant mesh in the forward gears - cars, trucks and bikes. Only the number of dog teeth on the selectors is different - many on synchromesh boxes to make them smoother and baulk less. Fewer on the non-synchro boxes to give you more time and displacement to get them home. (And not inconsequentially, each dog can be bigger and stronger).

    You can change any box without the clutch - all you need is accurate throttle control. The design however means that you have to be supremely good to do it on a synchro box, and if you stuff it up you wear the rings severely.

    Only the new zero shift design boxes can shift under power - all current designs need you to unload the shift mechanism - for any bike, road or race, bent selector forks is just user aggression. You can forgive a racer for heat of the moment stuff day in and day out and riding someone elses equipment that will be fixed after each race. 'Home' users - you pays your money, you takes your choice.
  18. The clutch lets the input shaft of the gb spin at a different speed to the flywheel. Then when the clutch lever is released, the plates slipping initially lets the engine catch up or slow down to match the input shaft speed, wearing the clutch. Good if you are a bad shifter, because a clutch is typically cheaper to replace then a gearbox, but with proper rev matching, makes very little difference to the wear in the gearbox.

    At the end of the day, id say, fug all difference if you can do it properly, but if you force it into gear all willy nilly, you can mess up your box.
  19. Good to know! I can't change gears without the clutch unless the revs are at the right spot, and I've never tried to force it (13 years of car lovin ain't too different to bikes). I put slight pressure on the gear level just as I throttle down and it slips into gear like when a man makes loves to a woman.

    Thanks all.
  20. No synchros in a motorcycle gearbox. Just sliding gears on slotted shafts with sliding dogs to do the dirty work (engage the right set of gears with the slots in the shafts they ride on).

    The dogs (which are basically just square-edged round teeth on the sides of the gears) and the matching holes in the sides of the gears eventually round off and can even come out of engagement under load. That's when it jumps out of gear.


    Trevor G