MC tranny question
 

There is one thing about sequential trannes that annoys me.

You can't drop one into neutral for EOCing.

Yeah, you can pull in the clutch and coast, but, that's a PITA and not as efficient.

Would it be possible to make a sequential tranny that had a neutral spot on the high side of top gear?

Yes, in fact an early Vetter competitor did that (but on the low side of top gear). Not being as well versed in m/c transmissions, don't ask me how, but it was probably a relatively simple change to that internal gear selector arm/plate/whatchacallit.

There are already detents for neutral and the other gears, it is a ball on a spring riding on a drum of sorts. Trick is figuring out how/where to add more detents so you can feel it with your toe.

Since the bike HAS to fully disengage one gear before engaging another, there is such a position between every gear, but the vetter guy just added one between 4th and 5th (top), perhaps with a dremel and careful analysis and complete disassembly.

I've accidentally found these neutrals many times, especially when learning a new bike.

Yeah, I've found them too, unfortunately.

After a few of those you remember to grab some clutch and wait till the tach dips back down below 10 grand before giving it another click......or you learn how to rebuild trannies.

Any reason no to just put a heavy duty free wheel on the motorcycle? seems like it would be easier to do then modifying the transmission.

Right on Ryland, I'm working on one now. It's a one way bearing (sprag) from a yamaha Rhino centrifical clutch. It will free-wheel after throttle decel, and be like nuetral in every gear, I'm pondering now of how to keep it clean & lubed while on the rear wheel??? Most starter clutches from any motorcycle work the same way.

What about just removing a cog? On a six speed that would mean pulling the 5th gear.

I don't use the clutch when up-shifting, I just learn to be more deliberate on the shift when I unblip the throttle, finding the sweet spot for clean shifts and not bending the shifter forks :) Never had to rebuild a mcycle tranny.


The mod is actually pretty simple, grind/cut a groove in the shifter detent drum, a dremel and a ruler and a sharpie are the essential tools. If you unscrew the detent ball retainer, you might even be able to do it without much disassembly, but I wouldn't count on it.

Also I would never give up bump start ability willingly. That has saved my butt many times.

Does anyone here have a picture of where we would need to dremel.

look up

slipper clutch
or
sprag clutch

slipper clutches are used in racing. they do allow some off throttle slipping, but not complete freewheeling. i believe they are used smooth out high rpm downshifts so they rear tire doesn't break loose.

High IQ already knew that. He was just testing you. ;p

I cut and pasted this from my gs250 manual, the real trick is figuring out where to put the other neutral detent(s) slots on the drum.

I would suggest finding the mid point of the neutral you want to add (i.e. between top gear and top gear -1) by:
1. put it in neutral on center stand.
2. remove detent spring thingie, take a look in the hole while you are there.
3. locate the neutral you want to add by hand. Split the difference between the two gears where the dogs just touch (spinning the rear wheel might help), gently lift or push down on the shifter to adjust. Use the detent hole to help get your bearings.
4. put a dab of prussian blue or something on the tip of the detent ball tip and install it to mark where the new slot should go. Then remove it, all without disturbing the shifter drum. Mark the location more permanently with a sharpie or scribe or something. Hopefully this leaves a clean mark, might need to try something else if not.
5. cut a slot with similiar dimensions to the existing neutral slot at the new location.

5 is easier said than done :) If you can devise a way to do it through the hole (if your bike has a hole) then cool, otherwise it is disassembly.


http://ecomodder.com/forum/attachmen...1&d=1327758077

:D

did a little reading on slipper clutches and found they are adjustable, so perhaps they can be into actual freewheels.

.....................

^LOLZ!

Without fail, those who feel the need to point out how smart they think they are, aren't.

Any questions on this response?

So, just to be clear, one would need to cut a grove similar to the one indicated by the circled 2 in the lower left hand picture between 5th and 6th gears? I can't ell by the picture, but I am assuming there is a slight grove between each gear, and it would just need to be deepened and widened?

Thanks,
Kirk

Yes, that #2 is a groove across the drum that holds the whole drum at that location for neutral via the detent ball/spring. It is a big enough groove that you can feel it with your toe through your shoe, but not so big that the drum can wander around. And if there were a properly located groove between 5th and 6th then it should probably work as a neutral up there as well.

I'm not sure if the other gears have detents, maybe. If you get a look in the hole and shift through the gears you will know.

I deleted the content of one of the posts in this thread.

Guys, if you can't play nice, just put each other on your "ignore" lists.

thanks

then delete his comment as well.

I'm pretty tired of the sniping and backstabbing.

Backstabbing?

Some folks need to log off and take a break.

Doug, you've earned every last bit of the jabbing you've received by being an ass. I've ignored a fair bit of negativity tossed my way and been nice, yet you keep on with it. You reap what you sow.

Don't be so damned thin skinned and learn to take other's inputs to your own thread with just a bit of grace and you'll be treated nicer.

'Cept maybe for Frank. That dude's like a pitbull!!!!!

Anyway, if I may un-hijack my own thread, I'd like to hear some feedback on my idea of just losing the next to top gear cog. I guess you'd have to have something in there. Maybe a spacer. Maybe you could just knock the teeth off the gear and put it back in. You just need to run the next lower gear a bit higher and remember to give it 2 kicks to get into high, 1 kick down to get back to neutral for EOCing. I think this would work better than giving it a timid half kick to try to find neutral between gears.