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Wandering Shift point problem.

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RON!!!!!!!!!. . .holy :dancingpoop: how have you been i haven't seen you on in forever. Sorry about the tranny problems but its good to see your still alive
 
Rob, it's been a looooooong time i know. Back here at last though !!!

See you yahpoo bud !
 
Thunder_Tiger_EB4_S2_Pro said:
Early shift ? late shift ? WHAT SHIFT !!!! This thing just will NOT shift and the tranny is BRAND NEW including the FOC that's fitted.

I followed the E/D's from traxxas to ensure all was ok and in the right place when fitting the FOC.

The tranny refuses point blank to shift even WITH the brand new primary clutch, hence my annoyance.
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So, i get my revo running, shift point seems ok. Second run, no adjustments it fails to shift, so i set the clutch to engage into second sooner (by a 1/4 turn). OK, all seems fine and shifting exactly where i want it to shift. Pull it in and stop engine, go home. Next day, clutch shifts too soon, but leave it and play for 30 minutes. Have to go out so put it away. Get back, fire it up, and it refuses to shift, no matter how much the engine screams its little heart out. set it back to original point, wont shift, so Re-set it back to the 1/4 trun point i made before, STILL won't shift.
Ok this is what I replied too. You've gotten a whole news trans since then? It still won't shift? What gear ratios are you using?

Did you mess with the new primary clutch before you put it in the new trans?
 
2revo1maxx said:
So, i get my revo running, shift point seems ok. Second run, no adjustments it fails to shift, so i set the clutch to engage into second sooner (by a 1/4 turn). OK, all seems fine and shifting exactly where i want it to shift. Pull it in and stop engine, go home. Next day, clutch shifts too soon, but leave it and play for 30 minutes. Have to go out so put it away. Get back, fire it up, and it refuses to shift, no matter how much the engine screams its little heart out. set it back to original point, wont shift, so Re-set it back to the 1/4 trun point i made before, STILL won't shift.
Ok this is what I replied too. You've gotten a whole news trans since then? It still won't shift? What gear ratios are you using?

Did you mess with the new primary clutch before you put it in the new trans?
Click to expand...

Nope, the primary clutch went in alongside the brand spanking new wide ratio gear set.

Check my previous posts, all the answers are there, I.E

Thunder_Tiger_EB4_S2_Pro said:
OK, so it' been a while since i started this thread, but an update is required.

New tranny arrived, as did the "long leg" wide ratio tranny gears.

Even with the new tranny and a brand new primary clutch i'm still having shift issues. I've had the engine professionally-tuned (even though i am more than capable to do it myself) and fitted new clutch shoes (and spring) to boot.

I have tried running on tarmac, still wont shift even when adjustments are made.

So today I fitted a brand new primary clutch (2nd new primary clutch to date) still not shifting into second gear. Tried adjusting it for over two hours and still nothing doing

This thing is driving me nuts to a point that I am about to give up on it and sling the thing in the cupboard.

There is no clutch slip, the clutch shoes are brand new, the clutch bell is not glazed, the tuning is perfect with standard ratio cb & spur gear, it sits on standard rims and tyres. all CV joint grub screws are tight and there is no binding in the drivetrain. The Tranny has a FOC.

Running on 16% fuel.
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Also, and please do not take this the wrong way, I am no slouch when it comes to running or tuning nitro rigs, it's just this has me stumped !

1 brand new tranny, 2nd brand new primary clutch, and various other new componants and it still refuses to shift.

See my point ? oh and where I refer to adjusting the clutch, it was at 1/8 turn intervals until 11/2 full turns was reached, when no gear change happened, the 1 1/2 full turns were reversed back to where it started. I tried that in both directions to no avail, i.e to bring the shift point lower or higher.

I am also aware of the following notes:

The transmission may not shift if the adjustment screw is turned too far in (locked in first gear), or too far out (locked in second gear). If the truck has quick acceleration and does not appear to shift, the transmission is never reaching the shifting point. The shift point needs to be lowered by turning the adjustment screw counterclockwise. If the truck has poor acceleration but very high top speed, the transmission is shifting into second gear almost instantly. The shift point needs to be raised by turning the adjustment screw clockwise.
 
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I've tried winding the slipper nut in and locking it tight, still no good. The Slipper pads, backplate etc has been replaced also and still no shifting.
 
these things are sent to try us AND THEY DO !!!!!

I have a trick up my sleeve that i need to try, if that fails, then I'm fitting one more primary clutch and if that fails, sod it, it will stay as it is in single speed trim.
 
Thunder_Tiger_EB4_S2_Pro said:
these things are sent to try us AND THEY DO !!!!!

I have a trick up my sleeve that i need to try, if that fails, then I'm fitting one more primary clutch and if that fails, sod it, it will stay as it is in single speed trim.
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I know how ya feel man. I didn't learn how to tune the easy way. I've spent many a frustrating night working on my rigs.

Let us know what it was if you get it.;)
 
I already know 2revo1maxx, i just have to test it to prove I got it this time !

Had the tranny out on my desk, think i sussed what the problem is at last, so i'll test tomorrow and see if I am right.

Just a pity I broke that darn front push-rod......................
 
Ok, so I finally broke the will of the beast and now I have it shifting !!!

After two hours stripping out the tranny, then robbing the good parts from three different primary clutches and making one good one, then rebuilding and refitting the tranny, all is well in the 2 speed department. Now, back to tuning that shift point. when was that ? oh YEAH, LAST YEAR ! grrrrrr

It seems the clutches all had issues, so the best parts from each were made into one good one and it worked ! Here's how it went down; i took the housing from clutch one, the spring and ball from clutch two and the clutch finger and hinge pin from from clutch three.

So ends a pain in the A$$ shifting problem.

At least it IS shifting..................Now, back to tuning that shift point. when did i start that ? oh YEAH, LAST YEAR ! grrrrrr

Oh crud....where on EARTH did i put my transmitter and glow ignitor...............clunk.....THUD.....OUCH !! well, now that i have found my transmitter by tripping over it, where's that glow ignitor..............Thunk...........OWWWWWWWWWWWWW That hurts........hmmmmmmm so THAT's where it went, UNDER MY FOOT, no wonder i fell over, it rolled under my foot !!

Better get outside before i do some SERIOUS damage to myself ! lol
 
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Oh goodness TT.....sounds like you had quite the good time with it. I know I have had the same thing before and it was buggersom as all hell to figure out. But like you said...as long as it works now right?
 
Yup, indeed it was a pain, but things that my father said years ago kept crossing my mind, like "never let anything beat you" or "never be beat" or "take your time and you will find the solution" and it helped and it got sorted in the end.

At least i will know what to do "next time"...............................
 

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