How to prevent Revo input gear from stripping...? - RC-Monster Forums

zeropointbug · **How to prevent Revo input gear from stripping...? -** 10.22.2007, 08:38 PM

Has anyone else completely ripped apart the input gear on the Revo tranny? Are there any metal gears that anyone knows of for the Revo tranny?

When this happened, all I was doing was speed runs up and down a smooth street, geared about 45mph. I wonder is this could be heat build up?

Other than replacing these gears all the time, if this is going to happen more, are there any other options?

riceman · 10.22.2007, 08:48 PM

I recently stripped a set in my Revo. I attribute it to landing a jump on throttle. I have since rebuilt it with the stock nylon but I did have a good look at Robinson Racing's offering. I may eventually got that route.

sikeston34m · 10.22.2007, 08:56 PM

Hi ZPB,

Sounds like you're running into the same thing that I encountered with the E Transmission. A couple of things that you might consider is sealing the case up with silicone around the edges, using sealed bearings in all the external locations and running a wet lube setup.

I believe if you set your mission goal to eliminate frictional heat and the ability to get rid of the heat that is generated. You will see alot of improvement in the longevity of your gear setup.

I have a Revo that I plan to convert to Electric, but since I'm still rounding up my parts, I haven't taken anything apart yet.

Here's a thought that I had concerning disappating internal tranny heat. Is there a way to install an aluminum or copper plate to act as a heat sink?

If there is, with a wet lube setup, the oil splattering around in there will carry the heat to the plate, then the plate will pass it to the outside where a fan or fins could be used to pass air. An "oil cooler".

I know your passing alot of power through that hot setup you have. I've been admiring your work for a long time. Let me know your thoughts.

zeropointbug · 10.22.2007, 08:59 PM

Yeah, that looks good to me, thanks riceman. Except, you know how we have to mod the 2speed clutch with screw? How are we going to use the steel one? Bummer.

The input gear looks good, but $100, ouch.

Another thing is the gear engager on the output gear, I really hate slack in the line, this just makes it hard on other gears in the tranny.

zeropointbug · 10.22.2007, 09:08 PM

Quote:

Originally Posted by sikeston34m

Hi ZPB,

Sounds like you're running into the same thing that I encountered with the E Transmission. A couple of things that you might consider is sealing the case up with silicone around the edges, using sealed bearings in all the external locations and running a wet lube setup.

I believe if you set your mission goal to eliminate frictional heat and the ability to get rid of the heat that is generated. You will see alot of improvement in the longevity of your gear setup.

I have a Revo that I plan to convert to Electric, but since I'm still rounding up my parts, I haven't taken anything apart yet.

Here's a thought that I had concerning disappating internal tranny heat. Is there a way to install an aluminum or copper plate to act as a heat sink?

If there is, with a wet lube setup, the oil splattering around in there will carry the heat to the plate, then the plate will pass it to the outside where a fan or fins could be used to pass air. An "oil cooler".

I know your passing alot of power through that hot setup you have. I've been admiring your work for a long time. Let me know your thoughts.

Wet lubricant sounds good, but I am really not sure if it would work with this. What kind of oil are you thinking? I wonder if shock oil would work. But, the resistance might be alot when you put so many rpm's through the tranny, it might draw excess current. Perhaps.

Might I add, this happened 3 weeks ago now, I have had my gmaxx single speed installed in it now, which is moe durable.

sikeston34m · 10.22.2007, 09:12 PM

I use Lucas Oil, it's a little thick to my liking but seems to work well. But even so, once the oil warms up it gets thinner.

I can't wait to get my hands on the new version of the E maxx transmission. If it holds up, I will continue my quest for more top end speed.

sikeston34m · 10.22.2007, 09:19 PM

Just to spin the transmission with my fingers, I can feel a small amount of additional resistence compared to a dry setup. But in thinking about this, when the rpm's are raging, the spinning gears move the oil away splattering it around the inside of the case. Centrifigal force only allows a small amount to stay on the rotating gears.

The faster everything is rotated, the smaller the resistence I believe. Just as long as the amount you put in the case isn't excessive. I only add enough to pool in the bottom of the case. Just enough to "wet" the lower 1/4" of the output gears. This way, each time rpm's drop, the oil is picked back up again and distributed around the internals.

My 2 cents.

sikeston34m · 10.22.2007, 09:29 PM

Hey ZPB,

You might wanna look around that site a little more.

Here's the input gears only, if that's all you need.

http://www.impaktrc.com/product_info...roducts_id=803

Much better price than the entire set.

BrianG · 10.22.2007, 09:31 PM

I've heard of this a few times now, even with wimpy Nitro motors. I wonder if it's a matter of raw power or speed? I've broken the shear pins, but never stripped a gear, but I'm only geared to about 35mph. I wonder if the heat buildup of high speed running is simply softening the gears until they are soft enough to break? Obviously, metal gears would help this.

I brought up a thought in another thread about the emaxx tranny. How about cutting some ventilation holes in a couple places (and on the bottom) to help cool the internals? Then, secure some screen material to keep the main debris out...

zeropointbug · 10.22.2007, 09:48 PM

About it spattering the oil around, thats true, that never occurred to me. I just don't know though, I have some pretty good mounting options with the single speed, and it's obviously more durable. But I also like some mounting options I have with the Revo tranny as well, and then I can use the Revo slider shafts, right now I am using the heavy duty half shafts, it's holding up, but I don't know for how long.

zeropointbug · 10.22.2007, 09:58 PM

Okay, great! That's much better than the whole set!

BrianG, yes, I am wondering about this myself. When it happened, it was on street, I had my 7s2p pack installed, and I can't remember what tires I had on, I think it was my RD Logic spike tires, which don't seem to have alot of bite on asphalt, I was some easy drifting though!

I mostly accelerated moderately, only a few times I really gunned it, but I did not lift the front end up, if seemed to be actually spinning the tires.

I wonder if a steel gear would prevent this... like it would have more thermal mass and absorb heat during high speed, perhaps?

10.22.2007, 11:10 PM

I'am to look at my revo to install/fit a Ofna Ultra LX 1/8 buggy center diff on my revo. If all fit like i want,.............talammmmmm!!!! no more trouble with the tranny. Pair with my RCM V1 hybrid diffs, souhld be a solid setup.

For answer to ZPB steel input gear, realy don't know if the Steel gear against the plastic 2-speed gear will hold up long.

And for the wet lub setup, forget it, the oneway bearing in the first speed gear will slip at fisrt run.