Author |
Message |
Twolls
| Posted on Monday, October 16, 2006 - 11:50 pm: |
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Checked the vault no luck. So... Is it permissable to shift and downshift without the clutch? |
Slaughter
| Posted on Tuesday, October 17, 2006 - 12:08 am: |
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Downshifting is possible but not advisable. Upshifting much easier. You have to RPM match in either case (referred to in some threads here as "blipping" the throttle - try using BLIPPING when searching... I'm not kidding) It really stresses the tranny if done wrong. Should be smoother on the new trannies (mine's an 03) Downshifting without clutch can be frightening at speed. |
Rr_eater
| Posted on Tuesday, October 17, 2006 - 12:14 am: |
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I slam up and down all the time on my 04S, works great when down right!!! Bruce |
Surveyor
| Posted on Tuesday, October 17, 2006 - 03:07 am: |
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Up=Yes Down=No Apart from the pain inflicted on the gearbox clutchless downshifts result in the rear wheel locking and sliding all over the place in my experience. I find that not only do I need to clutch for down shifts but I also blip the throttle which seems to stop the rear wheel breaking contact. |
Roadrailer
| Posted on Tuesday, October 17, 2006 - 08:01 am: |
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Unless you're racing (on the track) and need every extra 1/10th, why not just pull the clutch and not worry about the damage done by a botched clutchless shift? |
Jaimec
| Posted on Tuesday, October 17, 2006 - 08:44 am: |
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Yeah really. I agree with Roadrailer. What, do you guys think Buell put a clutch on his bikes by mistake?? |
Slaughter
| Posted on Tuesday, October 17, 2006 - 09:00 am: |
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The ONLY times I might do clutchless shifts is just one place at Willow Springs where the front is just coming down in Turn 6 (5/6 is over a rise, 6 is a right while the bike is really light) and I don't like putting the input into the bars just as the front is being heavily weighted. Other than that, the clutch works! I've got the heaviest spring made that fits a sporty clutch and I workout my grip. I forget how heavy the clutch is until I ride somebody elses bike or let somebody ride mine and get the comments. |
Bake
| Posted on Tuesday, October 17, 2006 - 09:47 am: |
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I save that abused for the dirt bikes, the clutch isn't that heavy or slow. |
Xb9ser
| Posted on Tuesday, October 17, 2006 - 05:49 pm: |
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I wouldnt recomend it. But it can be done. About 6 weeks ago my clutch cable broke about 12 miles from home. I shifted up and down by bliping trottle as I shifted. had to go threw two stop signs and slowed down real slow in first nothing was comeing so i ran them. got home ok. |
Tiburondriver47
| Posted on Tuesday, October 17, 2006 - 07:31 pm: |
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Maybe its different on the 06's cause mine will up or down shift by just touching the shift lever.I found out one day by just resting my foot on the shifter and it down shifted without me trying. I up shift and down shift without the clutch almost ever time i go out. I also used the clutch quite often. JMO. |
Twolls
| Posted on Thursday, October 19, 2006 - 12:47 am: |
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Thanks for the info guys. Most of the time clutchless shifting is on mistake |
Jackbequick
| Posted on Thursday, October 19, 2006 - 10:52 am: |
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You got it Steven. The loaded points of engagement in the transmission are called "dogs". They look like two matching, square cut, sets of notches that have to slide in and out of engagement as gears are selected. Straighten your fingers and slide them between each other, imagine that wrapped around and splined to a shaft and that is what transmission dogs look like. One dog's speed in controlled by engine RPM, the other is either driving or turned by the driveline. When you move the shifter the gears and dogs start moving to engage another pair. The clutch lets the disengagement/engagement take place with little or no load until the dogs are fully engaged. Matching the RPM of the dogs makes it happen quicker and more smoothly. To do it without a clutch, smoothly and minimizing potential damage, you would have to roll off the throttle to unload the dogs, move the lever, and, in the short instant of time as the sliding dog comes out of engagement the last gear's dog, use the throttle to match the speed of the next dog. Not an easy thing to do. For upshifts the engine RPM have to fall a little, for downshifts the engine RPM would have to increase. The RPM increase for downshifts is the "throttle blip". The blip is essential to downshifting without the clutch and also key to smooth, positive downshifts with the clutch. Done right, a blip is not just an uncalculated or random thing, it is subtle and the amount and timing has to be right. If the clutch is released just as the dogs pass at matched speeds, the engine braking is delivered to the drive line gently instead of harshly. The gear/dog wants to complete the movement by itself and not stop until a detent in the transmission is reached. If the high points of the dogs bump it stops or slows engagement, when that clears dogs drop into engagement, that is what accounts for harsh and abrupt downshifts. Standard truck and car transmissions are very different, they do not have dogs. The driver's hand starts, stops, and controls the rate and amount of movement in the gears. The speeds of the turning gears is matched by synchronizers and the driver can help that by increasing or decreasing engine RPM. Truck drivers seldom use their clutch except for starting and stopping. After you are in motion shifts are completed by backing off the throttle to unload the gears, moving the lever to align and synchronize with the next gear using the throttle to match the speed of the two gears. It is a beautiful thing if you like mechanical stuff. You could drive many trucks coast to coast across the United States, using the clutch only once at the start and once again at the finish if it were not for rest/fuel stops, stop signs, and stop lights. The modern motorcycle racers have speed shifters and slipper clutches and that makes up and down shifting very different for them. If you try to do what you see there without the same hardware it won't work the same. Jack |
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