I'm almost ready to run my t-maxx conversion the first time. I got the stock trans, fwd only single speed conversion. I have my RX8 2000kv on the way. What gearing should I go for running a 4s.

here is what I found on rc/nt site, I hope this helps. It helped me and I went from 22mph to 27mph on my Bone stock t-maxx 2.5 to et-maxx. I'm running 72t spur with now a 21t pinion and lots of fuuuuunnn:nod::nod::nod:


http://www.rcnitrotalk.com/gear-ratio-basics/

I hope i dont get in trouble for this link post:blush:

I'm doing a conversion as well. What battery trays are good to use?

I was looking into a novak tray for my build or maybe a custom tray with velcro straps.

I was messing around with ratio's last night to get around 35-40mph and I came up with 22, 24, or 26 pinion with a 64 spur. I think I will start with 22 pinion and the stock 70 spur, that came up around 30mph. Are you running an opti drive trans or the old style like me.

To all that are doing a conversion what are good tranny mods to do? I bought they fwd only kit and the single speed kit. What about gearing in side?

I haven't seen much, but you have to be careful with the optidrive and 2.5 trans, they have different gears. If anyone robinson racing might make a fwd only single speed metal gear kit but I doubt it. I'm just going to try stock gears with my tekin RX8 2000kv and go from there

Do you have the older black trans, or the new grey trans? Mine has the grey trans and I'm using 18 pinion, 54 spur, and it's pretty much perfect. Keep in mind I am using a 2650kv motor.

In mine I used Jammin CRT.5 / SCRT10 battery boxes. They stand the batteries up so you can fit 2 on the stock t-maxx chassis. I'm sure there are others that will do the job, these are just what I had laying around from my other trucks.

I didn't have a choice but to replace my gears with Robinson Racing gears. After a couple of runs, the stock plastic gears were shredded. I don't believe a metal single speed set of gears exists, for the t-maxx trans case at least, maybe there is a set for the e-maxx trans. Next thing to go is the center to rear driveshaft, make sure you have a couple spares, or upgrade them.

DCM0070- Its too bad you're on the other end of the state, if you were closer you could check mine out first hand.

Ok I dont know how you do it but I'm only able to quote one at a time. lol.
anyway here are some pix of my et-maxx and the break down of what I have done.
1. converted my original 2.5 2spd tranny to a ($8ish) single spd with the traxxas kit and also removed the reverse gear.
2. battery tray homemade plexi glass and $3 screws and nuts.
3. aluminium bracket free(found at work) just made holes:lol: a little cheap looking but working on a nicer one.
4. 80a hobbywing xerun esc $75
5. 2200kv 800w 540 motor ($35) so far highest temp reached 130degrees f.
6. robinson racing 21t pinion $12- the rr spur gear was original from the nitro engine.
7. Another small plexi glass on top of the old throttle servo mounts with valcro for the esc.

I am using a racing chassis and restricts room for batteries so I just stack them on tray. Oh by the way white foam cushion for batts.


http://i213.photobucket.com/albums/c...1/IMAG0042.jpg
http://i213.photobucket.com/albums/c...1/IMAG0029.jpg

http://i213.photobucket.com/albums/c...1/IMAG0030.jpg

http://i213.photobucket.com/albums/c...1/IMAG0031.jpg

http://i213.photobucket.com/albums/c...1/IMAG0035.jpg

http://i213.photobucket.com/albums/c...1/IMAG0036.jpg

http://i213.photobucket.com/albums/c...1/IMAG0038.jpg

Thanks for all the help guys it is certainly going to help my build.

Looks good, I'm a little worried weather your battery tray will stand up to the abuse, but time will tell. It was practically free, I get that, not trying to rag on ya. I only worry cause the motor mount I made from .125" (3mm) aluminum bent from landing too hard a few times. I like where the esc is mounted, good call.

Just gotta ask, what is up with your steering linkage? Did you accidently install the steering bellcranks on the wrong sides of the truck, and just said F it? :lol:

As for the multiple quotes, lol, you just hit the "mq" button right next to the "quote" button on every post you want to quote, the button will change color. Then when you're ready just hit the "add reply" button at the bottom.


Just an update on my own truck. As I said above, the motor mount bent towards the back of the truck pulling the motor away from the spur, so it's out of commission at the moment. I'm pretty sure I'm just gonna get an FLM emaxx chassis and see if I can get my t-maxx trans on it. If not, I'm gonna have to get the e-maxx trans, and sell my t-maxx trans since it's got Robinson Racing steel gears and all brand new bearings in it that have only been used for about 4-5 batteries. Money is a little tight right now, but I will update when I make some progress.

I should have got the reverse mount from how2rc and just mounted the battery in the back. Nice build tho, I didn't think about using that throttle servo mount for my esc. It also sounds like 20-24t and the stock 70T should be money for gearing, what speeds are you reaching and how torque'y is it with that gearing.

mine is the older trans, the non optidrive, I'm pretty limited on spurs because of that.

I think my biggest challenge will be mounting a single 4s or just giving up and mounting 2 2s's

soloracer- I didnt know there was something wrong with my steering. I've had this set up for the last 7 years. Never had any problems what so ever. "if it aint broke why fix it" oops:lol: I've beat the truck up pretty good and no problems with the motor mount. I think because it sits so low there is no room for flexing. Although if I want to change the spur gear I have to make another one. I have a 66t that I tried a dry fit and it was a no go, pinion didnt even touch a tooth.:(

redskull- with a 72t spur and 19t pinion my top was 22mph then I got a 21t pinion and toped out at 27mph. I just got a 66t spur but I need to modify the motor mount becuase of the diameter of the 66t is smaller. But I'm pretty happy with my current set up. It's very torqy and quick even when I put some bigger tires and it still lifts the front end but not as much. Which I like cuz I'm kind of tired of back flips and keep breaking my body post's.

I have the 22, 24, 26 pinions and a 64 & 66T spur in my wish list, so I should have lots of room to play around with the gearing. Have you checked out how2rc, he has 3 styles of motor mounts for $22 shipped, they have room for gearing mesh adjustments. Once the USPS gets my parts delivered out here, I can get to a roller and post some pics.

lol not bustin balls, was just curious cause as far as I can remember, all of my maxxes came with a short linkage to the bellcrank, and it uses the one right next to the servo, i know my current one does

And I had meant that the battery tray might not withstand the abuse, not the motor mount. That motor mount looks very solid :)

Why did you guys decide to do the electric conversion?

I personally wanted something different and beefy. I like the challenge it has brought, I learned my vehicle inside and out. I also got the satisfaction that I didn't take the easy way out and buy an e-maxx chassis:D