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Duneable Override Spring Balance And Adjustment

11K views 12 replies 7 participants last post by  camatv 
#1 ·
Feel free to add to this or correct anything that I say that is wrong and I will edit and correct as needed.

I had the opportunity while I had my motor and trans apart to take a couple pictures and explain something about what those 3 little springs in a "DUNEABLE" override actually do.

Many people think those 3 little springs do nothing. They think that they may have to try to keep a gear pushed against a huge amount of force. That is actually NOT what they do.

Those little springs are only there to keep the slider gears in a neutral/middle type position and not engaging cogs left or right of it that would be spinning in the wrong direction or speed depending upon what gear the transmission is in. Of course helping to not break gears or wear/bend shift forks.

It is important to have the springs length and tension adjusted so as to have the slider gears sort of floating in between the other gears when not engaged so if the transmission is turned backwards by hand there will be no binding. The transmission should turn freely by hand both forward and backward in each gear.

When installing an override or replacing shift forks if the transmission will only turn backward about 3 turns in any gear before binding then you have a spring not holding the slider gear away from the gear that the dogs on the slider gear are supposed to miss.
 
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#3 ·
Here is a picture of the slider to the left and right as it could be without the springs. I am using a flat blade screwdriver to push the slider left and then right. Spring tension should be adjusted or balanced so the slider is held in between the other gears allowing them to spin past and not engage. They will be very close but shouldnt hit.
 

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#4 ·
Picture of the dogs that should miss each other and not engage if they are in a different gear when turned by hand backward in gear , these were engaging slightly in 3rd gear and the transmisssion was binding after a few turns in the wrong direction/ backwards. This is how they are after I fixed it and you can see they will not hit now. I stretched the spring closest to the sprocket a little to adjust it and now all gears turn freely in both directions.
 

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#9 ·
Just curious, who's duneable override are you running? what gears are cut, and how has it held up?



I tried a whitaker duneable overide. well actually 3 different ones, none lasted more than 5 minutes and i got tired of replacing tranny parts. went back to stock.
 
#10 ·
The term "duneable" is misleading.

They are more forgiving but you still have to be careful with backloading.



I have lunched a few parts in mine. I quit backloading it and haven't had an issue in two years.



Rick
 
#11 ·
This one is a whitaker duneable. I try not to backload it but I always do and I am pretty hard on it. I had a problem with 3 rd gear because I jumped my bike and backloaded it hard and messed up the fork bad caused one of the larger springs to jump over the snapring causing it to jam up in 3 rd gear and either lock up or freewheel. It was an easy fix but I think if it would have had the springs adjusted correctly like I showed it would not have had a problem.
 
#12 ·
So, if one were to take a regular overide trans and install the 3 springs then would it be a "dunable" or are there other changes?





I know when I spin the overide on the bench backwards, then 4th gear starts to bind but probably wouldn't with the springs. That is my thought.
 
#13 ·
nice write up todd.



anyone that has purchased one of these should have the instal instructions with it.



i personally havent been running a spring assisted lately. i prefer the good old std override anymore.
 
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