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hard to shift out of first


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my 01 rm 125 runs great but when i try to shift up from first it normally just pops out of gear and not into second,

i get it to shift best by shifting quickly and not fully leting off the gas then keep pressure up and you can feel it drop in gear

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What's with people not using the clutch? Isn't that like extremely impossibly bad for your transmission? It's made there for a reason..am I wrong..?

you are wrong. it is made to get going from a stop and coming to a stop. going between the gears without the clutch can be done effortlessly and not do a bit of damage. ive put 24k miles on my streetbike with no clutch(other than 1->2 and 2->1 when crossing N). no problems at all. the gears are all meshed, all the time. all you have to do is let off the throttle while preloading the shifter, and it slips smooth as can be into the gear. it is almost unnoticeable when done right.

now if you are trying to get from 1st to 2nd(or the other way around), it may be tougher without the clutch because it is a longer shift(neutral is in the middle)

edit:

when i had my girlfriend on the r6 the first time, she didnt even feel the shifts other than first to second. clutchless is really that smooth.

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What's with people not using the clutch? Isn't that like extremely impossibly bad for your transmission? It's made there for a reason..am I wrong..?

The bikes transmissions are built to not use the clutch, if there is no load on the transmission that is (not on the throttle).

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i would try taking the shifter off and moving it down one notch on the spline i had the same deal with my yz250 and it ended up justbeing because it was at an awkward angle with my boot. just worth a try and see what happens before spending any big bucks

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We'll then what's with all these people that say "I might have accidentally clutchless shifted but I don't remember doing it" when there engine is seized, or something of the sort?

Also, then what would be the point of a rekluse?

clutchless shifting wont seize the motor. running a tranny without oil will seize the tranny. running an engine without oil will seize the engine. not having the proper ring gap can seize an engine. overheating can. a number of things. maybe if they clutchlessly downshifted and over revved the piss out of it, it could pop the motor. the clutch doesnt actually do anything with the gears. it only takes the power from the engine away from getting to the tranny. when you let off the throttle for that split second, you are effectively doing the same thing. there is a brief moment where there is play in between the dogs and the gears. that allows you to move out of that gear, and into another

the reason for the rekluse is to be sure you wont stall it. an example: if im riding a really tight technical trail on my 250 smoker and have to put my foot down and slip, i may forget to grab the clutch. no matter if im stopped, the bike wont stall. i can wreck with the bike tire slammed against something, and it will not stall. i can lock my rear brake up, and it will still be running. it also makes life easier if you have to go that slow so you dont have to clutch all the time.

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clutchless shifting wont seize the motor. running a tranny without oil will seize the tranny. running an engine without oil will seize the engine. not having the proper ring gap can seize an engine. overheating can. a number of things. maybe if they clutchlessly downshifted and over revved the piss out of it, it could pop the motor. the clutch doesnt actually do anything with the gears. it only takes the power from the engine away from getting to the tranny. when you let off the throttle for that split second, you are effectively doing the same thing. there is a brief moment where there is play in between the dogs and the gears. that allows you to move out of that gear, and into another

Hmm..and you're sure about this?

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Hmm..and you're sure about this?

i do it every day on my crotchrocket and thats about 20 miles each way shifting all the time due to stoplights and all. neighbor does the same on his motard. still no problems with either.

just take a look at how the transmission works. what holds you in a gear is friction between the gear slots and the dogs(as well as the shift mechanism, but that can be negated as it is used both ways). when you pull the clutch, that friction is taken to near zero. when there isnt much friction, it lets the dogs slide in and out very easily. when you let off the gas, the same thing happens. the momentum from the wheel is keeping the transmission spinning, where the engine braking is trying to slow down. when that happens, instead of the dogs pushing the front of the slot, the back of the slot is pulling the dogs. obviously, there is a small gap where there is no friction in there(not long at all). when you preload the shifter, you are letting it switch as soon as that friction is released, but before the other friction is applied. a similar feeling can be felt by you when you let off the throttle in first or second, then hit the throttle again. there is a slight moment where the chain is in between pulling and being pulled due to the slack.

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When you say preload the shifter, do you mean put pressure on it, and then when you let off the throttle that same amount of pressure will now move the shifter up to the next gear?

Also, do you have any pictures of a transmission and the "Dogs"? I can hardly understand when I'm just reading it. I've looked on Howstuffworks to learn how a manual tranny works, but can't quite seem to understand. I've never taken apart my bottom end before.

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...Also, do you have any pictures of a transmission and the "Dogs"? I can hardly understand when I'm just reading it. I've looked on Howstuffworks to learn how a manual tranny works, but can't quite seem to understand. I've never taken apart my bottom end before.

no pictures, and a caveat: it's been a while since I was in a gearbox. But the ones I worked on have two shafts. One shaft turns with the clutch. The other shaft turns with the sprocket. If you have a five-speed, you have five pairs of gears (each shaft has five) and their teeth mesh together all the time. The gears are all different in diameter (duh). Each pair of gears has one gear that's locked to its shaft, and one that's free-spinning on the other shaft. So when you're in neutral and stopped with the clutch out - the shaft on the clutch is spinning, the shaft on the sprocket isn't. So the gears attached to the clutch shaft are spinning too and spinning their partner gear. The gears attached to the sprocket shaft are NOT spinning, and neither are their partners on the clutch shaft. They alternate along the shaft - one locked, one free.

When you're NOT in neutral, what happens is you take one of the gears that's locked to its shaft and slide it so it grabs one of its free-spinning neighbors. It has 'dogs' which are just pins sticking out sideways from the gear. So now you've locked a pair of gears together on one of the shafts and what was a free-spinning gear before now acts like it's locked to the shaft. So off you go....

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When you say preload the shifter, do you mean put pressure on it, and then when you let off the throttle that same amount of pressure will now move the shifter up to the next gear?

Also, do you have any pictures of a transmission and the "Dogs"? I can hardly understand when I'm just reading it. I've looked on Howstuffworks to learn how a manual tranny works, but can't quite seem to understand. I've never taken apart my bottom end before.

ok...here is a picture of the full tranny...

Another_preped_motorcycle_transmission_from_Performance_Design_c.JPG

and here is a picture of just a few gears...

gear1.jpg

if you look at the shift forks, you can see little discs under there. those are what connect to the inner shafts in the tranny. when the shafts are spinning, these spin at the same speed. when they are moved left or right, you can see the dogs(nubs on the gears) slide into the disks, and that makes the output shaft spin at a proportionate speed.

and yes, by preloading, i mean applying just a little pressure on the shifter

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Holy crap, thanks for that!

I can honestly say I understand this stuff now! You explained it great, along with a great quality pic!

One thing I'm not getting though, is how does the shifter move these shift forks? Clicking up and down doesn't seem to be able to be translated any way into moving the forks haha.

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Holy crap, thanks for that!

I can honestly say I understand this stuff now! You explained it great, along with a great quality pic!

One thing I'm not getting though, is how does the shifter move these shift forks? Clicking up and down doesn't seem to be able to be translated any way into moving the forks haha.

there is an item called the shift drum that is rotated by the shifter. it is a ratcheting mechanism when you shift. here is a picture of the drum, a shift fork, and the star mechanism i guess it is(i think it is actually called a shift pawl?). if you look at the forks in the picture from before, you can see little pins on the forks. those slide into the drum(you can see the channels they ride in), and then when the drum rotates(due to the little pin connecting to the star), the forks slide the disks from earlier, engaging a different gear.

IMG_0151.jpg

Hope this all helps

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