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pre-loading shifter and clutch timing


hiro
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The fine details...  Should I shoot for shifting simultaneously with the throttle release/clutch disengagement or slightly after? I'm not trying to clutchless shift. Just make the shifts quicker and smoother.

I've been pre-loading my shifter more recently while also using the clutch. I've noticed a tendency for the shift to complete about the same time the clutch lever approaches my other two fingers, not after. Is that OK as far as wear, or should I tweak the timing or shifter pressure a little?

Also, the shifter will move a tiny bit then stop if I apply a little more pressure than usual. Is that something that I should do or avoid?

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You should only preload-shift when you are able to control throttle enough to sync rpms.  Otherwise you'll be wearing gears and dogs.  Some bikes, (like big, slow v-twins) are nearly impossible to sync, which is why you'll see cruiser riders take forever to shift, while pulling the clutch in completely, dropping throttle, then hammering the next gear, then slowly releasing.  ... One reason I cant stand to ride those sort of bikes.   when you are able to sync throttle, the throttle and clutch lever should barely move as you up (or down) shift, unless you are under very hard braking. 

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I was just thinking. Wouldn't keeping pressure on the shifter increase wear a little on the shift forks?

In the future, maybe I'll just make contact with the shifter without much pressure. I don't really want it to shift automatically as soon as I ease up on the throttle.

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Right...no pressure until you're ready to shift.   The less pressure you apply to shift, the less wear.  Its very difficult to master a perfect downshift while braking...keep practicing!

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43 minutes ago, Qman said:

Right...no pressure until you're ready to shift.   The less pressure you apply to shift, the less wear.  Its very difficult to master a perfect downshift while braking...keep practicing!

I was mainly talking about upshifting. Blipping for downshifts is a whole different thing for me. When I get it right, I feel awesome! If I get a buck or double rev, I feel embarrassed and disappointed. heh

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8 minutes ago, MidgetTodd said:

Clutchless. Learn your rpms and bang those shifts out. N and 1st are clutched

Yeah, I've been studying the constant-mesh transmission and see how clutchless upshifting works. I had no idea before that shifting could be so different from a car. I did come across a video in which a guy describes reducing throttle, pulling in the clutch, and upshifting simultaneously. I think that's what I started doing. I probably don't get the RPMs right because it isn't always smooth. That's why I've been adding clutch, just in case. I can't imagine downshifting this way though.

I guess I just need to spend more time feeling it out.

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1 hour ago, hiro said:

Yeah, I've been studying the constant-mesh transmission and see how clutchless upshifting works. I had no idea before that shifting could be so different from a car. I did come across a video in which a guy describes reducing throttle, pulling in the clutch, and upshifting simultaneously. I think that's what I started doing. I probably don't get the RPMs right because it isn't always smooth. That's why I've been adding clutch, just in case. I can't imagine downshifting this way though.

I guess I just need to spend more time feeling it out.

You'll never get it if you try to figure it out analyzing every possibility.  Just Try some RPM matching on upshifts & see what happens.  When you do it wrong your bike will tell you. When you do it right your bike will tell you.  If you suck at it, your mechanic will tell you.

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2 hours ago, MidgetTodd said:

Clutchless. Learn your rpms and bang those shifts out. N and 1st are clutched

Unless you do it perfectly every time, you are tearing up the transmission.  Dont clutchless....unless you have shift assist pro by BMW!?

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44 minutes ago, Qman said:

Unless you do it perfectly every time, you are tearing up the transmission.  Dont clutchless....unless you have shift assist pro by BMW!?

The gears are always meshed, so I think it's different. Only the gear dogs interlock or release from each other. Unlike a car that will grind gears. I guess if it's done really bad, the dogs might not be happy. Not 100% sure.

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Hmm...how much force is exerted by a shift fork to hold the gears in place? Dont' they constantly rub metal against metal? I thought only pre-loading the shift level too much would exert force on the shift forks. (I guess it doesn't matter too much because I can't change the design! I just have to not break it!)

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20 minutes ago, hiro said:

The gears are always meshed, so I think it's different. Only the gear dogs interlock or release from each other. Unlike a car that will grind gears. I guess if it's done really bad, the dogs might not be happy. Not 100% sure.

19 minutes ago, hiro said:

The gears are always meshed, so I think it's different. Only the gear dogs interlock or release from each other. Unlike a car that will grind gears. I guess if it's done really bad, the dogs might not be happy. Not 10

20 minutes ago, hiro said:

The gears are always meshed, so I think it's different. Only the gear dogs interlock or release from each other. Unlike a car that will grind gears. I guess if it's done really bad, the dogs might not be happy. Not 100% sure.

Apply enough force and you're grinding gears.  Ask why a worn tranny will want to fall out of 2nd or 1st into neutral.  Metal on metal is always going on, with oil as the buffer.  And you're right, the dogs take the major beating.  

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4 minutes ago, hiro said:

I imagine the gears would be stressed, but not grind. I don't want to try, but could gear dogs barely connect and grind?

Just use minimal force, dont do clutchless, and your modern tranny will last longer than the rest of your bike.  On the other hand if you want completely constant mesh, get a honda DCT tranny, as found in F1.

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8 minutes ago, Qman said:

Just use minimal force, dont do clutchless, and your modern tranny will last longer than the rest of your bike.  On the other hand if you want completely constant mesh, get a honda DCT tranny, as found in F1.

I'm confused enough with one clutch. haha Actually, I get the clutch. Synchros, not so much.

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12 minutes ago, hiro said:

I'm confused enough with one clutch. haha Actually, I get the clutch. Synchros, not so much.

Test rode the Africa Twin DCT....pretty slick!...pun intended!  Seamless.

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1 hour ago, Qman said:

Test rode the Africa Twin DCT....pretty slick!...pun intended!  Seamless.

Wow, I want to try one now. I don't know if I should study the DCT or keep the head clear to work on my shifting. Odds are I won't have a DCT any time soon.

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