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Unable to change gears at a stop

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IDL
2/14/2008 12:00:31 PM
Sometimes when I roll up to a stop light or something I am unable to downshift when at full stop or going really slow.  Sometimes I get into neutral and can't go up or down.
 
It only happens on occasion, but I think it's starting to get more common.
 
It's annoying when it happens because obviously I want to get it into first gear before the light turns green.  I find that if I rev the bike sometimes I can shift, or sometimes I shift up from neutral into second because that is sometimes easier than getting it into first.
 
Anyone know what can cause this?
mycvil
2/14/2008 1:09:00 PM
Perfectly normal - just get it into 1st while you are still rolling (MSF trained that one). - Mine does the same - revving may/may not help, rolling the bike Fwd/Back or slightly releasing the clutch seem to allow it to shift while sitting at lights.
RojerLockless
2/14/2008 1:26:55 PM
quote:

ORIGINAL: IDL

Sometimes when I roll up to a stop light or something I am unable to downshift when at full stop or going really slow.  Sometimes I get into neutral and can't go up or down.

It only happens on occasion, but I think it's starting to get more common.

It's annoying when it happens because obviously I want to get it into first gear before the light turns green.  I find that if I rev the bike sometimes I can shift, or sometimes I shift up from neutral into second because that is sometimes easier than getting it into first.
Anyone know what can cause this?


Sticky gears.. its ok.. what you need to do is let your clutch out just a bit and it will let you shift down
IDL
2/14/2008 1:31:01 PM
Interesting, although is it possible for the bike to start doing it more often?
I don't think I've changed my riding habits but notice it more.  Sometimes even when rolling
 
Maybe I need an oil change..
RojerLockless
2/14/2008 1:49:47 PM
na generally most honda just have stiff gears and sometimes it happens.. if you engage the clutch a bit then put it back on you can shift back down jsut fine
ffingers
2/14/2008 2:14:29 PM
yep +1 on what they said...i read somewhere that it has to do with some sort of safety feature...i don't remember why...but they are meant to be stiffer and have trouble engaging if you don't downshift all the way while slowing down....

the easiest thing is to one) train yourself to downshift when coming to a stop; and two) if it happens...just slightly release the clutch to the friction point and quickly pull it back in and it will allow you to get all the way down...

i'll see if i can figure out the safety thing if i find it....made sense when i read it...
bergs
2/14/2008 2:23:36 PM
Try doing all your down shifting at higher speeds.
 
Most bikes I've ridden don't really like to go from 6th to 2nd at 10mph.
 
 
jfunkRR
2/14/2008 2:52:14 PM
My old F4i did the same thing, would pop into neutral sometimes when I wanted 2nd gear or wouldn't shift into first at a stop.  Feathering the clutch in and out or rocking the bike back and forth solved it for me.
 
My new 600RR hasn't done it, yet...I hear this is a common thing with honda's so it's not much to worry about.
IDL
2/14/2008 4:08:04 PM
Next time it happens i'll try the clutch trick
 
I shift to first at stop sometimes just because I find the 'clunk' annoying when shifting into first at any speed.
 
Out of curiousity, why is it best practice to shift into first while moving?  Is it for safety reasons or something like that?
thirdgenlxi
2/14/2008 6:41:28 PM
Yup yup... like everyone has mentioned already, completely normal.

Here's a little more in depth into as to why it won't shift into gear when stopped.

Unlike a car transmission, motorcycle transmissions are constant mesh NON syncronized.  The gears have what's called "dogs" on one gear, and "grooves" on the mating gear. They act similar to syncronizers in that the end result is the same.... locking any given gear to the mainshaft or countershaft.  But they're still quite different.   When you shift to engage a gear, it moves the gear with the dogs, which is called a "slider gear", and moves it to either the left or right, depending on which gear you're engaging.  The slider gears have splines on the center hole, which permanently attaches them to their respective countershaft or mainshaft.  The grooved gears are freespinning on bearings.  When you engage a gear and the slider gear moves over and meshes with the grooved gear, it then locks that gear to the respective countershaft or mainshaft, whichever it happens to be on.  Once that gear is locked to the shaft, powerflow can be achieved.

Here's a few pics to help explain.  These particular gears (in the first pic) are 2nd gear on the left, and 6th gear on the right.  As you can see, 6th gear is the slider gear, and has "dogs" on both sides of it. 2nd gear has the "grooves", and is freespinning until it is locked to the shaft by 6th gear.  If it slides one way it will engage 2nd gear, and when it slides the other way it will engage 3rd gear.  Although these are 6th and 2nd gears, 1st works exactly the same.  It uses 5th gear slider to engage 1st. 






The dogs and grooves have to line up in order for the gears to mesh.  This is why the gears have to be moving in order for them to mesh.  When both gears are sitting still, if the dogs and grooves don't line up, the dogs will just bang against the non-grooved parts of the mating gear, making it unable to engage and lock that gear to the countershaft/mainshaft.  The grooves are slightly wider than the dogs, allowing them to engage and disengage at speed, but also makes for some play in the drivetrain. This is why you get a slight "clunk" with each gearshift, and also  why when the engine is off and bike is in gear, you can rock it back and forth several inches, and it feels real 'loose'.  Just the dogs sliding back and forth a little bit inside the grooves.  The shift fork rides in the little slot on the black gear, right between the actual gear part of it, and the dogs on the right side


And when they're engaged




I know that probably sounds really confusing.... I suck at trying to explain stuff   But hopefully that gives you a general idea of how it works and why it won't go into 1st gear while you're stopped without rolling a little bit, or letting the clutch out first
ARay
2/14/2008 7:38:32 PM
it has gotta be a honda thing. my vtx did it also. letting the clutch out a little always worked for me

thirdgenlxi
2/14/2008 7:48:24 PM
quote:

ORIGINAL: ARay

it has gotta be a honda thing. my vtx did it also. letting the clutch out a little always worked for me



It's not a Honda thing, it's a non-syncronized transmission.... that's how they work.  It doesn't matter what brand it is, Honda/Kawi/Yamaha/Suzuki/ect.... all of them will have the exact same issues going into gear while stopped
slip_
2/14/2008 11:08:16 PM
Sweet, thanks for that very in depth explanation lol.
IDL
2/14/2008 11:20:31 PM
quote:

ORIGINAL: thirdgenlxi

Here's a little more in depth into as to why it won't shift into gear when stopped.


 
Wow thanks!
That totally explains it, dude that was awesome.
oodayvidoo
2/14/2008 11:42:16 PM
yeah uuummmmmmmmmmmmmmmmmmmmmm....


.... what jared said!!! =)
kukku
2/15/2008 12:31:48 AM
Great explanation. Don't mean to hijack but I have a gear question: when changing from 1st to second I can see the neutral light coming on for a split of a second. Does this has to do with the non-sync transmission or is it my sloppy changes? Thanks for any feedback. 
fishfryer527
2/15/2008 5:16:23 AM
quote:

Does this has to do with the non-sync transmission or is it my sloppy changes?

 
1-n-2-3-4-5-6 or Five up, one down. You pass through N on your way to 2 from 1 and vice versa. You may still be a dirty, filthy, sloppy, naughty gear changer, but the green blink in normal. 
jfunkRR
2/15/2008 8:08:54 AM
My old F4i had this same light blink, and I figured it was from the 1-n-2 so I never worried about it, but it also used to "pop" into neutral when I wanted 2nd, and if I was romping on it a little it was embarrasing because I would let the clutch out and throttle it and it would just rev in neutral, and I probably scared the crap out of some "golf balls" when I was moving down the road and I'd hit the rev limiter.  My 600 RR has yet to do this...so maybe I'm getting better at shifting...I don't know...or maybe I wasn't lifting my foot enough to engage it?  Over time I just learned to over-exaggerate when going from 1st to 2nd, but I don't ride that bike anymore so I don't have to worry.  I told the kid that bought the bike off me and he said it was anormal thing, and after reading Jared's awesome gear changing post, now I know why.
 
FYI - "Golf Balls" is a term coined by my old man, for the lil' old ladies that drive with two hands on the wheel and look thru the steering wheel over the hood, and all you can see is the perfectly round poof of white hair driving the car.


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