Author Topic: grear shifter  (Read 3339 times)

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Offline CB750 SS

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grear shifter
« on: April 11, 2008, 07:37:17 AM »
I did what many would call a top end rebuild or a freshening of my motor and have a question.  basically all the seals and piston ringers, etc.  I used the info on this site to determine what to change.  At this point the engine is back (painted) and looking pretty complete.  I've replaced the clutch and now I working on the gear shift. 

BTW - I didn't pull out the transmission during the process as I worked fine and looked good.

So the gears seems to work well going "up" but they won't come "down"...what gives?  Do I need to reassemble the shift mechanism with the gears in a certain place?  thanks, 

Offline mystic_1

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Re: grear shifter
« Reply #1 on: April 11, 2008, 07:57:54 AM »
If you pull off the mission cover (rear left side), you can put the gear change lever back on it's shaft and work the mechanism with the cover off.  There's probably something awry with the selector arm or drum stopper mechanism.  This assumes that you didn't split the crankcases, if you did that it's possible the shift forks are not in there right, but I'd bet on the selector mech.

mystic_1
"A ship in harbor is safe, but that is not what ships are built for."
- John Augustus Shedd

My build thread:  http://forums.sohc4.net/index.php?topic=68952.0

Offline CB750 SS

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Re: grear shifter
« Reply #2 on: April 11, 2008, 08:10:52 AM »
split the crankcase - I did but basically left everything in the bottom as my goal was to fresh the seals and their wasn't anything wrong with the gears. I didn't pull the transmission or crank. I even left the clutch basket in place.

Offline mystic_1

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Re: grear shifter
« Reply #3 on: April 11, 2008, 08:14:30 AM »
Well, I'd still start by pulling the mission cover and checking things out.  Being able to upshift but not downshift definitely sounds like a selector problem to me.  If necessary you could even strip off the selector mech and drum stopper.  Then you could rotate the shift drum by hand to see if it changes gears.  That would assure you whether the shift forks are in there ok. 

mystic_1
"A ship in harbor is safe, but that is not what ships are built for."
- John Augustus Shedd

My build thread:  http://forums.sohc4.net/index.php?topic=68952.0

Offline CB750 SS

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Re: grear shifter
« Reply #4 on: April 11, 2008, 08:20:12 AM »
I just did that and I can go "up" and "down" with out the drum stopper in place.  Does anything know how to replace the drum stopper?  I can find a good picture off it.  The way I did it (per my poor pictures and diagram) limited the l "C" looking stopper (name?) from spring back up.  Does anyone have a good picture of how it's supposed to look?  thanks,

Offline mkramer1121

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Re: grear shifter
« Reply #5 on: April 11, 2008, 08:23:22 AM »
what bike?  mrcycles.com has good exploded parts diagrams in thier fiche that you can print out.

Offline CB750 SS

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Re: grear shifter
« Reply #6 on: April 11, 2008, 08:55:07 AM »
and there we have it.  Thanks!

Offline mkramer1121

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Re: grear shifter
« Reply #7 on: April 11, 2008, 01:00:14 PM »
and there we have it.  Thanks!

No problem, I fought with mine at first, now its no problem with the diagram

Offline kghost

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Re: grear shifter
« Reply #8 on: April 11, 2008, 08:38:48 PM »
Great next time ya might find the right forum for your question. ;)
Stranger in a strange land