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Old 01-24-2012, 09:50 PM   #1 (permalink)
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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?


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Old 01-24-2012, 10:04 PM   #2 (permalink)
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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.
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Old 01-24-2012, 10:25 PM   #3 (permalink)
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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.
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Old 01-26-2012, 04:04 PM   #4 (permalink)
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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.
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Old 01-26-2012, 07:04 PM   #5 (permalink)
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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.
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Old 01-26-2012, 10:04 PM   #6 (permalink)
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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.
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Old 01-27-2012, 07:37 AM   #7 (permalink)
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What about just removing a cog? On a six speed that would mean pulling the 5th gear.
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Old 01-27-2012, 07:46 AM   #8 (permalink)
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Quote:
Originally Posted by pete c View Post
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.
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.


Quote:
Originally Posted by Ryland View Post
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.
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.
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Old 01-28-2012, 01:19 AM   #9 (permalink)
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Does anyone here have a picture of where we would need to dremel.
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Old 01-28-2012, 02:38 AM   #10 (permalink)
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look up

slipper clutch
or
sprag clutch


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