TRX-4 Gearing options

[Jerold]

Does anyone know of any larger spur gear options for the TRX-4 with the two-speed trans?

It has the 45T spur at the moment, which is the largest one Traxxas recommends/sells.

I can always do the underdrive diffs, which gives me about 13% reduction (3.09:1 -> 3.5:1).

I've tried smaller 9T pinions but, when they get small, they just start howling.

Looking at the manual, and a little math, the Total Teeth Count (TTC) is between 54 and 61.

So in theory I could us a something like a 52T spur and a 9-12T pinon; however, I have no idea if it will fit in the trans case?

 

[inddirt]

Are you trying to slow it down?

 

[Jerold]

Are you trying to slow it down?

Yes, slow it down or reduce the gearing. So bigger spur or smaller pinion.

 

[Chubaka]

$10 rc4wd or axial motor if it's brushed?

I'm assuming training mode on the esc if factory would not work as you still want all power just not the rpm?

 

[inddirt]

Higher turn brushed motor, under drive gearing, 50% training mode, 2s lipo instead of 3s, etc.

 

[Jerold]

Slowing it down isn't exactly right, I want more torque and control with lower gears. Slower is a byproduct of the gearing.

I'm running a Holmes Hobbies TrailMaster Sport 550 Brushed Motor (21T) with a HobbyWing 1080 ESC on 3S. It's a good combo.

However, I ordered the HobbyWing Fusion 2300KV on sale and will be swapping to that later in the week. More run time means smaller batteries, less weight, it's super quiet plus torque control, blah blah.

My goal is to gear it down and not have it make all kinds of noise from the tiny pinions.

 

[inddirt]

I have the axe 550 3300kv on my defender and after last firmware update, its slowest speed is so slow you can't tell it's moving unless you stare for a while. Oh and the torque is crazy even at that low speed. Can send a dropbox link of a vid

 

[Jerold]

I have the axe 550 3300kv on my defender and after last firmware update, its slowest speed is so slow you can't tell it's moving unless you stare for a while. Oh and the torque is crazy even at that low speed. Can send a dropbox link of a vid

Dang. You've convinced me.

I guess I will see how I like then mess with it if I need to.

Thanks!

 

[inddirt]

I ordered smaller pinions also. Installed the 12t that came with it and haven't changed a thing. Plenty fast in 2nd speed. Almost too fast if there's such a thing.

 

[Jerold]

I ordered smaller pinions also. Installed the 12t that came with it and haven't changed a thing. Plenty fast in 2nd speed. Almost too fast if there's such a thing.

I put it in yesterday and gave it a test run. It is SUPER quiet, so now you can really hear the squeak in the trans. LOL.

It is so smooth, I was testing it in 2nd gear and didn't realize it. Definitely a nice upgrade.

 

[inddirt]

I'm glad you're enjoying it. I've put 1 in the trx6 also and not looking back. Very happy with that purchase