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I have a problem..

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g0dspeak

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alright well I'm not sure if my revo is the 2.5 or the 3.3.. but it has the OptiDrive system.
it sat for 2 years or more up in my attic. got it down, got it running, and whenever i try and go forward it barely moves, even with full throttle. i replaced the spur gear since i saw the teeth were badly chewed up. that wasn't the problem. so i took the transmission apart and everything seemed just fine in there.
i believe its the optidrive system.. in the manual its telling me that if the throttle trim is messed with then the system will need to be re-programmed.. could that be the reason that it wont even shift into any gear by its self?
when i move the shifter button on the controller, it doesn't shift like it should.. and i have no clue what is up.
 
I have the REVO 3.3 and found that the slipper clutch was too loose when it did not want to change into 2nd. First make sure that it is tuned properly (adjust HSN, then LSN then idling and then the HSN again) before you make any changes to the slipper clutch or tranny settings.
 
From your description it's difficult to tell exactly what your issue is as chewed up spur teeth don't usually muck with your optidrive settings.
The optidrive serves two functions in life.
The first is to keep an idiot from shifting their vehicle in reverse (or forward) while the vehicle is moving as that could really mess some stuff up.
The second is to piss you off and it's hard to tell which it's best at.
If you mess with your controller settings - such as reset 70/30 to 50/50, you gotta reprogram the optidrive.
You can remove the optidrive if you don't want reverse or are smart in when you engage it.
You can live with optidrive if you can figure out what sets if off and how to reprogram it.

How to reprogram it:
http://www.traxxas.com/products/nitro/revo/revo25/resources/Revo-OptiDrive-setup.pdf

Worst case - if the optidrive is your issue you can resolve it - and if it's not, you can eliminate it from being your problem.
 
TGL said:
From your description it's difficult to tell exactly what your issue is as chewed up spur teeth don't usually muck with your optidrive settings.
The optidrive serves two functions in life.
The first is to keep an idiot from shifting their vehicle in reverse (or forward) while the vehicle is moving as that could really mess some stuff up.
The second is to piss you off and it's hard to tell which it's best at.
If you mess with your controller settings - such as reset 70/30 to 50/50, you gotta reprogram the optidrive.
You can remove the optidrive if you don't want reverse or are smart in when you engage it.
You can live with optidrive if you can figure out what sets if off and how to reprogram it.

How to reprogram it:
http://www.traxxas.com/products/nitro/revo/revo25/resources/Revo-OptiDrive-setup.pdf

Worst case - if the optidrive is your issue you can resolve it - and if it's not, you can eliminate it from being your problem.
Click to expand...

thank you. well i tried reprogramming it, i had no luck. the green light doesn't flash when i pull the throttle. i might take it to the hobby store and have them replace it or something....
 
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It sounds like your slipper clutch, or more likely the clutch on the motor itself. I would bet it's the clutch.
 
DreamState said:
It sounds like your slipper clutch, or more likely the clutch on the motor itself. I would bet it's the clutch.
Click to expand...

i dont think it is... when i move the shift button on my controller, it doesn't do anything. its not shifting into gear at all. and when i have it running, it just doesn't go..
 
you mean when you try and put it in reverse the servo doesn't even move?

Take the body off and look at the spur gear and clutch bell gear. When you hit the gas do they spin fast, slow or not at all? Does the engine rev. or bogg when you do that also?
 
Last edited:
DreamState said:
you mean when you try and put it in reverse the servo doesn't even move?

Take the body off and look at the spur gear and clutch bell gear. When you hit the gas do they spin fast, slow or not at all? Does the engine rev. or bogg when you do that also?
Click to expand...

the spur gear is brand new, and the clutch bell is fine. theymove when i hit the gas. the engine revs up good.. i think the problem is the optidrive, it doesn't shift at all. doesn't shift into forward or reverse.
ok i started it up, and i tried going, and for some reason the tranny isnt engaging.
 
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well i might try and sell it on craigslist, for parts or whatever.. the engine is good but i just dont have much time or money to put into it anymore lol, no time for it..
 
Expect to get about $50 out of it. Try bypassing the opti drive and hook the shifting servo right into the 3rd channel on the receiver.
 
bergoff said:
Just bypass the optidrive. They are a pain to deal with. Hang in there you will get it.
Click to expand...

i tried bypassing it, but half of the wires are hardwired into it. the ch3 and shift in are hardwired i think. ill have to look, but right now i gotta go take a shower..
 
g0dspeak said:
i tried bypassing it, but half of the wires are hardwired into it. the ch3 and shift in are hardwired i think. ill have to look, but right now i gotta go take a shower..
Click to expand...

Clip.:) I'd snip whatever wires you have to. Make sure your slipper's adjusted properly after the truck's moving.
 
this is what i have, the throttle in and shift in are both hardwired..
fvz5as.webp

r72j3b.webp
 
The servo connectors look normal in the pictures. Just hook the servos directly to the rx. That would clean a huge nest up too. Get a fail safe though.
 
Metalhead Matt said:
The servo connectors look normal in the pictures. Just hook the servos directly to the rx. That would clean a huge nest up too. Get a fail safe though.
Click to expand...

and the rx is what? sorry, i know next to nothing about these cars. could you help me out and explain a bit better? any help would be greatly appreciated.
 
Rx=receiver. Just hook the steering servo to channel 1, throttle to channel 2 and shifting servo to channel 3. Get a failsafe to go in between the throttle servo and receiver. If you run out of range or your batteries go dead, a failsafe will automatically set the throttle servo to a pre-designated spot that you set it too.
 
Metalhead Matt said:
Rx=receiver. Just hook the steering servo to channel 1, throttle to channel 2 and shifting servo to channel 3. Get a failsafe to go in between the throttle servo and receiver. If you run out of range or your batteries go dead, a failsafe will automatically set the throttle servo to a pre-designated spot that you set it too.
Click to expand...

i tried it, still had throttle and steering. but the clutch isnt grabbing or something..i have the slipper tight.. any more and it will break it...
 
OK, you have throttle and steering so it sounds like you can eliminate the optidrive as being your problem.
Describe what you are doing and what is happening.
For example - pre-start - Controller on and Revo on - do you have full throttle control?
If you take off the air filter and blip the throttle, does the carb open up all the way?
If you let off, does it close down to where it should be to idle (1mm gap)?

Air filter on:
Can you start your Revo?
If you blip the throttle does the engine rev up?
If it revs, does it move forward or just sit there?
If it sits there, like DreamState mentioned, it sounds like your engines clutch is the issue and not your spur gear - so I wouldn't worry about the slipper (spur gear) unless it's spinning and the truck is going nowhere.
 
Ok, this is easy to figure out if you use the process of elimination. The engine is making power and sending it out and that power is leaking out before it gets to the wheels some where.
With the truck running
1) rev the engine... Is your flywheel spinning... is your clutch bell spinning...
is your spur gear spinning.
2) Lift up the truck and look under it, when you rev it.... are the drive shafts coming from the tranny spinning...

If everything but the driveshafts are spinning and you have already correctly bypassed the optidrive, than your slipper is free spinning our you have one or more tranny gears slipping.

I have had fwd only conversion for awhile so I don't remember, but can't you just disconnect the linkage going from the servo to the opti and manually put it in gear? Just to check it.
 

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