[mason.pine]

Was riding my bike when I tried down shifting into first gear without pressing the clutch in (I know, really dumb of me to do) anyways I had stepped down on the shifter when all of a sudden I heard a snap. I had stopped to check what the matter was, realized the shifter was no longer grabbing any gears it was loose without any tension. When I pulled the shifter out I was able to put it into neutral start the bike backup and put it into first gear but it would just slip back in a little bit and wasn’t able to grab a gear without pulling the rod out at a certain point. I think I’m going to have to take the right side cover off where the clutch sits, but I don’t know if I have to order any parts or if I broke something major, I’m decently mechanically inclined. Tell me what you guys think

 

[Troy Jollimore]

I am willing to bet that what happened is that the shifter shaft, which is short, snapped at it’s end inside. That end has what looks like a three-pronged fork sticking up from it. That fork interlocks with a similar fork on another, longer, shaft, which continues across the engine, towards the clutch side. Not the best of designs, as the teeth on these forks can become misaligned or stop touching each other. It’s also not uncommon for that ‘snapping’ to occur. Many have had to have the fork welded to the shifter shaft.

If you drain the oil and remove the right side crankcase cover, you can see all the way in through the crankcase, so you should be able to see the two forks together. They should be even. Reach in and feel how solid they are together. If you’re lucky, @swifty2014 might attach a picture of them. I don’t have it handy… 😉

 

[swifty2014]

Yes you will see what is happening with the right cover off.
A couple of guys had a weld break on the right side shift shaft. They re-welded it and all is well.
Or the circlip may have broken on that holds the shift plate in position.
Here is a video of what the shifter does and this one has a slipping problem.

 

[swifty2014]

Shift spindle teeth aligned and right below is the weld that was broken off and needed to be welded=

 

[mason.pine]

okay thank you! Seems like a big job I’m just hoping it isn’t costly and I can find parts. So if I weld the forks would that stop the shifter rod from sliding in and out because I still don’t know why it would be doing that since it’s not even supposed to be knocked off its teeth in the first place. Also I can still pull it about 3 mm out and get it to shift into 1st
The

 

[mason.pine]

I’ll have to take it apart tomorrow and let yous know what I find but looking at the video you sent it seems that it could be that gear select piece, when I pull it out a bit it’s able to switch gears (kind of) it doesn’t want to switch gears only when I pull it out at the right position. There must be a spring broke or something making it be able to come in and out like that?

 

[swifty2014]

If the left side shift shaft is loose there must be a problem with the retaining clip in the left case.
Maybe that would be the best choice to look into. It should be pretty solid not moving in and out.
My 1983 750 barely moves in and out.

 

[mason.pine]

Okay so pulling both sides off tomorrow then what kind of oil does it take (don’t have a manual) also should I change the filter while I’m at it?
I know it shouldn’t go in and out as much as it does even if it’s only 5 millimetres it goes from being pushed on with no tension what so ever free play on the rod but when I pull it had the tension just don’t know what makes this tension..

 

[mason.pine]

The rod would also slip and make the same snapping noise when trying to put it into hire gear than 1

 

[mason.pine]

Will be talking more tomorrow when I get the covers off and have a better look at the situation, hoping there’s no extreme damage and can be easily fixed. Thank you again!

 

[swifty2014]

Just take off the left side I think you will find the problem there. The right shaft is probably still holding fine by your description of excess play on the left shaft.

 

[mason.pine]

Oky thanks, would you know the type of oil I should put in?

 

[PhantomRider64]

Oky thanks, would you know the type of oil I should put in?

You just opened a big can of worms with that question.

Just get the Honda GN4 oil in the viscosity that works best in your area. If the oil is close to being changed then yes change the filter as well, again I suggest a Honda filter.

Eric


Sent from my iPhone using Tapatalk

 

[mason.pine]

How do I get this off also the gear shifter is going in and out and I still don’t know why does it have a cotter pin at the end of it by the teeth ?

 

[Troy Jollimore]

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Those teeth were supposed to be removable. Cotter pin may have been for that? If the shaft does move, the teeth can get misaligned. So you can usually only shift one gear in either direction.

 

[swifty2014]

It will move in and out when the cover is off. You don't need to take the flywheel apart.
The shaft is held in position by a circlip and a washer to keep it snug.
Did the circlip break or slip back on the shaft? Do you see both of them in there?

 

[mason.pine]

Yes I do it looked like the circlip was meant to be up there but was very confused why it was up by the gear, tried moving it but it wouldn’t budge is why I figured it was in a groove but okay that is exactly the problem. Where exactly does the clip and washer go on the gear shaft?
how am I to know if the teeth line up exactly right? Is there only one way it’ll go in or could it potentially only connect one tooth ?
also is the shaft supposed to move sideways/up and down when the cover is off?

 

[swifty2014]

The clip should be near the outer end and when the cover is put on the washer will ride on the cover and the clip will hold it there. Should see a groove or marking where it was for years. Yes the shaft will be loose with the cover off.

 

[mason.pine]

So can I take this rubber off the casing then put the circlip and washer behind the rubber? That’s the only way I figure it would hold the gear rod out, because when it’s pushed in it doesn’t connect with the teeth but when it’s out it only then locks in with the teeth.

 

[mason.pine]

Also what oil filter should I get? I seen a discussion you were in saying you used the Purolator L14459 would that fit my ‘84 750?