Revo won't go to WOT.... Help

[Revo1978]

Hey guys, I have a revo i just recently bought and had the old 27mhz radio in it. I bought a flysky gt3b and went through the setup with the optidrive. My problem is that it won't go full throttle. It did with the old controller when set to 70/30.

I should add that it is 2.5 with the 3.3 in it.
So far I have tried
- moving the end on the carb slide
- moving the horn on servo.

The only way i can get it to go close to wot is to set the trim all the way back.
Seems like the servo doesn't have the power to push it all the way or something. The slide is nice and free!

Only thing i haven't tried is to turn the carb to see if i can get a better angle.

Is this caused by the 70/30 of the old controller? Is therw something that I am missing from setting up the flysky? This is frustrating me greatly!
All input welcomed and appreciated!

Thanks

[metoo2]

You didn't mention servo travel adjustment. Have you tried that?

[Revo1978]

Do you mean endpoint?

[Revo1978]

I just tried the endpoint to 120% and no difference. my servo pulsates aswell. not a lot but enough, hold it full throttle and u see it go back and forth a few milimeters.

[96motorhead]

if it is moving a lot get a new servo that happened to mine and a new servo fixed the problem.

[Lincoln87]

i too had a similar problem, the throttle servo could not throw the carb open to WOT (its a 2075)

If i pushed the linkage it would get to 99% WOT, and if i used my fingers on the slide itself it would go WOT..

I adjusted the little thing on the carby (where the LSN is) to angle more towards the back end of the truck and it works ALOT better now (I still reakon its not WOT, maybe 99% but better than what it was before)

[Revo1978]

Yeah well i have a new servo ordered! Enough fooling with it. I set the endpoint to 120 took the horn off, hit the brake a little, reinstalled and used some trim. Now opens to 99 percent! I did try moving the thing on the end of the carb to. I'm thinking the spring is way to heavy, its the tightest spring I've seen on an rc. May try a lighter spring if i can find one!
She got Los of power, flip over on its roof no prob from giving it a blast if throttle. Its not perfect but its working....but why not have bigger endpoints? This must frustrate a lot of people!

[zdragon71]

With a 2075 servo that spring wont be too heavy. It will pull faster too.

[goodie1977]

No guys... You missed a key point. He went from a 27Mhz radio to a new radio and has an OptiDrive. Traxxas has 3 models of OptiDrive. They all have the same part number. The only difference is the color of the work SET. You must have the newest OptiDrive with the word SET in RED for the Traxxas 2.4 radio to work. It may not work at all with another manuf radio, but rest assure that if you have an old OptiDrive from an old 27Mhz radio setup...IT WILL NOT WORK WITH A 2.4G setup. Done lived and learned this one myself. See message string and quote below on the topic:


http://traxxas.com/forums/showthread...ti+drive+model

Ok just to add some more to this topic, I got a reply from Traxxas with regard to the OptiDrive units and basically it is summed up as follow:

SET in Red - Works with 2.4GHz radio and is the latest revision of the OptiDrive unit
SET in Black - Works with 27MHZ radio and has fail-safe.
SET in Silver/Grey (I've yet to see silver/grey but perhaps it's white) - Works with 27MHz and does not have fail-safe, so basically the earliest version.

[Lincoln87]

for the spring i have got a nitro 4tec throttle return.

[traxxas revo 3.3]

my revo has the same problem is just adjusted the the servo and it seemed to work but now i am having other problems with compression which isnt related to the servo adjustments.

does anyone know how to change a piston and sleeve cause i thought my revo had good compression till i put wd40 in it and know it has got nearly non at all.

[goodie1977]

does anyone know how to change a piston and sleeve cause i thought my revo had good compression till i put wd40 in it and know it has got nearly non at all.

Uh, thread hijack... but yeah, it was posted in the traxxas site and a very easy operation for anyone with basic mechanical aptitude.

[Kahabut]

I had a very similar problem recently. There was nothing wrong with the servo, it's just that the traxxas throttle horn pivot is a bit dubious. I found a couple of solutions.

First, be 100% certain your servo is in good shape. Then, check and see if when you hold 100% throttle on the radio, can you move the carb with your finger? If you can, the problem isn't the servo, it's the dodgy throttle pivot horn. I put a notch in mine with a rotory tool, about 1/3 of the way down. Large enough to catch and hold the carb piece. What this does is prevent the carb from being "loose" in the horn, and thereby deflecting, instead of opening all the way up. YMMV