downshift from 4th to 3rd grindy

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james
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downshift from 4th to 3rd grindy

#1

Post by james »

Hello to everyone,
1952 Panhead foot clutch tank shift.

Upshifts like butter.
Downshift from 4th to 3rd goes bddddddddddddchunk into gear.
like a clutch problem not totaly disengaging.
Not the case. Been through the clutch several times, all ok.
Down shift from 3rd to 2nd ok actually everything works fine
except for 4th to 3rd.
I can change rpm and speed to make it change a little but usually I expect
a grind from 4th to 3rd.
Trans oil 50 weight and it's full.
Belt drive primary and it's not too tight.
All other gears are working fine up and down.
What are your thoughts?

Thanks, Jim
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Re: downshift from 4th to 3rd grindy

#2

Post by RUBONE »

Worn shift clutch dogs, worn shifter fork, worn third gear dogs, or some combination of them! Early shifter clutches are not relief ground for third gear and along with pre '59 third gear bushings being prone to wear make it very difficult to engage. Holding pressure on it to do so overheats the fork and wears the edges of it (and can also bend them!) making the problem worse and worse over time! Most likely scenario is going to be getting into the box itself for replacement of worn parts!
Robbie
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Re: downshift from 4th to 3rd grindy

#3

Post by jdpan »

Ratchet shifter pawl springs broke?
58flh
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Re: downshift from 4th to 3rd grindy

#4

Post by 58flh »

Sounds like worn shift forks or dogs on the gears as ROBBIE has already pointed out!--I just went thru a tranny not to long ago & it was both of those problems!--The guy kept riding it like that for some time & constant mashing on the shifter when downshifting caused the forks to be out of ADJ> & bent!--So the sooner you get into the box the better!--Also it might help when you downshift from 4th to 3rd to hit the throttle a little!-(raise the RPMs)-at the time of downshift!, Its not a fix but it might help on the grinding & forcing of the shifter. Although you probably already tried this!. GOOD-LUCK RICHIE
james
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Re: downshift from 4th to 3rd grindy

#5

Post by james »

Thanks for the replys guys.
Winter project.

Jim
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