atunink

I have a Traxxas Revo 2.5R that I have upgraded to a 3.3 with a 14t cb and a 40t spurgear. I was breaking in the new engine and when I finally got to tank #5... The transmission wouldn't shift into second gear. I have adjusted the slipper clutch and also adjusted the tranny to shift sooner thinking that would do the trick. I have also reset the optidrive. I'm not sure where to go from here. I have read that there is a collar that could be loose on the shaft inside the transmission and may need tightened. But... That article was for the Maxx trucks. Does anyone have any advice for me? I am capable of tearing into the transmission but I just thought some wise words and advice from others might be a good idea before I tear into it.. Thanks.

piddlefoot

Sounds like what happens when its to rich. It cant get the revs up enough to change, does it sound like its bogging down ?</p>

atunink

Not at all... She's runnin like a champ! It sure sounds to me like there is plenty of rpm's.

atunink

If I was to remove and open up the transmission, is there anything in particular I should look for?

RCCanuck

was it shifting before the engine and gear change? if so then it isn't the tranny...how tight is your slipper?

Snook Man

The revo tranny is dfferent than the early model (black tranny) Maxx's. The collar/clutch is attached with a pin to the primary shaft and not a set screw like the early maxx' tranny used.

Sounds like a tune or slipper clutch adjustment is needed.

piddlefoot

Is any part of the drive line stiff at all ?

atunink

None of the drive line seems stiff... I have yet to adjust the carb in any way, I just finished breaking in the engine. It is running pretty good, I should only have to lean up the high speed needle a bit. As far as the slipper clutch goes... I rebuilt it and have tightened it a couple times. I suppose as the new pads get worn in it will need further adjusting. I can probably try and tighten it up a little more and lean the carb a bit. I just have a feeling it may be something more. It was running great and seemed as though it should have been shifting... I will look into things a bit more. Thanks guys for all your help... It may be a while before I get the time to get it out again but I will post my results soon... Thanks again...

piddlefoot

You havent adjusted the carby after run in ? Lean it ! My first post becomes relivant again ! Definately try that first, poor tune will slow the engines 'pick up' and give it less overall topend. You gotta tune digger !
It should sound like a motor bike on steriods with powerband if its tuned !

michaelwash

I'm having the same problem. And I think the tune is not the problem. I would like to know is there a factory set point for the tranny?

atunink

Ok... I took er out the other day and ran the s**t out of it!!! Tuned the carb... Leaned it up quite a bit... Its running really good... Still wont shift!! I have the slipper clutch adjusted on the tight side. I am completely baffled.. I plan on taking it out one more time to see if I can further tune it and possibly get it to shift. If not, not sure what my next step will be. Take out the transmission and check it out I guess, though Im not really sure what I would be looking for.. Thanks again guys.. If anyone has any other ideas... please post. Any help on resolving this will be appreciated...

Mr Max Wheelie

well im kind of a newbe but my maxx 3.3whichi steady chase the tune up and down on does this same thing when its too rich........also again im no pro but that gearing seems a lil odd to me,my new tmaxx came with a 22 tooth bell and a 58 tooth spur and my buddies new 3.3 revo came with a 20 tooth bell and a 54 tooth spur,im not saying ur gearing is wrong im just thinking maybe its something to look at b4 tearing into the tranny,by my 4rth tank of fuel during break-in my maxx was trying to shift intosecond...........anyway thats just my 2cents and maybe thats all it worth but good luck and let us all know how ya make out!!!!