Author Topic: Won't shift into FOURTH??? updated 12/5 - fixed  (Read 17063 times)

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Offline KB02

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #25 on: November 02, 2009, 03:19:25 AM »
...bump...

Any suggestions on what to look at???
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Offline HedNut

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #26 on: November 03, 2009, 10:05:42 AM »
Don't know if this will help?... but this is a pic I took right after I pulled the cover on my bike (although...my bike never ran since I got it, so who knows what con'd it's shifter is in!?...I don't think anybody monkied with it)....it's a 78' K


Offline MRieck

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #27 on: November 07, 2009, 06:43:47 AM »
 Is your nuetral switch positioned correctly and set completly into the case? If it is not the shift drum will move around and not allow shifting especially in upper gears. Just a thought.
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Offline KB02

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #28 on: November 08, 2009, 07:22:36 AM »
That is something I will have to check this morning. I had some problems with getting that in to begin with, so I'm hoping that might be it. I REALLY don't want to have to pull the engine.

And it's a beautiful fall day, too. I nice day for a test ride.   ;D
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Offline MRieck

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #29 on: November 08, 2009, 04:39:59 PM »
That is something I will have to check this morning. I had some problems with getting that in to begin with, so I'm hoping that might be it. I REALLY don't want to have to pull the engine.

And it's a beautiful fall day, too. I nice day for a test ride.   ;D
Be sure to push the shift drum all the way in.
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Offline KB02

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Re: Won't shift into FOURTH??? (updated 11/18)
« Reply #30 on: November 18, 2009, 04:35:06 PM »
So I was able to spend a little time working on the bike and here is what I have found:

With the neutral switch out, the shift drum would slide a little bit further in. It still did not allow any further upward shifting. Sliding the drum in or out still did not allow any additional shifting. With the neutral switch out, it did allow the drum to slide, so I know that it has to be in there.

Looks like I will have to pull the engine.  :-\ :-[
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Offline Trav-i

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #31 on: November 19, 2009, 11:17:45 AM »
I had a simillar situation last week durring some test and tune rides, but involved second gear not fourth.  And Monday I found the problem with the help of Andy750.  My problem was not obvious and took me twice looking in the shift mechanism to find.  My problem was the bolt above the shift drum (if you look straight at the end of the shift drum you will see it at about the ten oclock position near the stud with springs on it), it had backed out so far it was getting shift linkage and screwing up the works.  Not real obvious, but as soon as I tightened it back up my shifting went right back to normal and has worked flawlessly since.

Hope this helps.

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Offline scondon

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #32 on: November 19, 2009, 03:33:56 PM »
    When putting the cases together there is one shifter fork that is in the lower case transmission assembly that must be properly joined to the shaft in the upper case transmission assembly. This fork selects fourth gear in the transmission. I reassembled an engine and had the fork sitting on TOP of the shaft, rather than around it. Bike ran fine, but popped out of 4th and into a false neutral. When I split the cases to fix it there was no damage to the fork and I was able to simply reassemble the cases correctly and ride.
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Offline KB02

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Re: Won't shift into FOURTH??? (updated 11/1)
« Reply #33 on: November 20, 2009, 04:55:51 AM »
Well, Trav-i, I'm pretty sure it's not that bolt, but it is one thing I'll check as I start pulling the engine apart.

Scondon, I have a feeling that your suggestion may be the problem. I'm hoping for Trav-i's suggestion, though...  ;)
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Offline KB02

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Re: Won't shift into FOURTH??? updated 12/2 - need quick response
« Reply #34 on: December 02, 2009, 07:52:36 AM »
I need a quick response on this as I have the day off and don't want to have to do this again.

Take a look at the pictures below:
Do I have that center shift fork in upside down?




The second picture is less blurry, but the first one has the better angle.

Here is the Fiche:
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Offline mystic_1

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Re: Won't shift into FOURTH??? updated 12/2 - need quick response
« Reply #35 on: December 02, 2009, 07:55:02 AM »
Look at the pin on the shift fork where it engages the shift drum.  If the fork were upside down, that pin wouldn't engage properly.  I believe you do indeed have it in upside down.


Suggestion, dry-fit the case to check for fitment and proper transmission operation before gluing it all back together.

mystic_1
« Last Edit: December 02, 2009, 08:01:54 AM by mystic_1 »
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Offline MCRider

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Re: Won't shift into FOURTH??? updated 12/2 - need quick response
« Reply #36 on: December 02, 2009, 07:57:59 AM »
Mystic beat me to it. To repeat, does the pin that is supposed to engage the drum, look like it will in fact engage the drum when assembeled. hard to say in the picture, But I'd say its in upside down.
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Offline ron.cieri.313

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Re: Won't shift into FOURTH??? updated 12/2 - need quick response
« Reply #37 on: December 02, 2009, 08:00:15 AM »


+2...here's reference photo from my tear down
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Offline KB02

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Re: Won't shift into FOURTH??? updated 12/2 - need quick response
« Reply #38 on: December 02, 2009, 08:06:52 AM »
Yup! It's upside down. Sweet (kinda... :-\ ) I have found my problem.

Thanks for the quick responses. Took all of 8 minutes! This place is AWESOME!!

The center shift fork has the nub right on the back of it. Unlike the other two forks, which are on the side. Hence my idiocy in putting it together wrong.

Thanks again, guys. I started my day by falling down my stairs. Looks like things are going in a better direction.  :D
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Offline KB02

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Re: Won't shift into FOURTH??? updated 12/5 - Fixed
« Reply #39 on: December 06, 2009, 03:15:53 PM »
Well, the cases are back together, the linkage all in place and test shifts conducted. Looks like my problem is all taken care of. Now I just have to get the engine back in the bike... of course, they're predicting snow the next few days... figures...
1978 CB750K Project
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Offline nobody

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Re: Won't shift into FOURTH??? updated 12/5 - fixed
« Reply #40 on: December 06, 2009, 07:01:42 PM »
Glad to hear it's all coming back together man.
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Offline HedNut

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Re: Won't shift into FOURTH??? updated 12/5 - fixed
« Reply #41 on: December 07, 2009, 04:41:13 AM »
That's great to hear, getting things sorted out!....sorry to hear about the snow, it's 7 deg F here...with a good 2 inches of snow tha looks like it's here to stay.  Good thing mine doesn't run yet....i'd be upset.   CHEERS!