noob e-revo?

[rchotrodz]

I am planning on making an e-revo with the e-maxx trans and motors with the exv esc but I see alot of people are using a bec or is this used if only using the revo trans with a brushless motor? please help...
Thanks

[Hickoryhead]

A BEC or UBEC is used depending on the set up of your RC. I take it your using all the stock Emaxx stuff correct? What batteries and how many cells? Most or all ESC's have an internal BEC. They can only handle so much from the batteries you plan to use. I have an Emaxx tranny with a MM ESC. I plan to use 2s2p Lipo's ran in serious. I have to wire in a UBEC to handle the Lipo's. The internal BEC of the MM can't handle 4s. I hope this helps.

[rchotrodz]

well for now I am going to use everything stock until I see how it handles so stock exv esc and 12 cells so I don't think I would need the ubec unless I went to lipos correct? Also if I use the e-maxx trans can I still use the 2 speed or do i have to lock it in 1st or 2nd gear? I appreciate any and all the help I can get pics of where to dremmel out on the revo chassis would help if possible...
Thanks

[Hickoryhead]

I can't say yes or no to that. I don't have hands on experiance with the EVX. Like I said before your ESC is rated for so many volts or cells that it can handle. You need to see how many volts or cells the EVX can handle. If it can handle 12 cells then you should be fine. If not then you need a UBEC. You don't need a UBEC just because you are using Lipo's. Here's and old thread but it may help you:

http://www.rc-monster.com/forum/showthread.php?t=576


As for the tranny being locked into 2nd its up to you. You "could" leave it so you could shift it. But think about the mods you would have to do on the chassis. The Emaxx and Revo shifting servo are not in the same place. You would have to modify things for that. Plus more wires to run. More work then needed IMO. 2nd gear locked in is easier on the motors, ESC, and batteries. Think of it like this. Have you ever tried pushing a manual shifting truck? Which gear is easier to push it in 1st or 5th? You motors are pushing your RC truck. Which gear is going to be easier? Just my opinion. Its easy to modify the tranny. Brian has some pics if you need help. I used everthing in that was in the tranny already. 3 holes and 3 bolts later mine was locked. That easy.

here's another link to Brians pics:

http://scriptasylum.com/bl_conversions/

[BrianG]

Just to be clear: The Revo doesn't need a servo to shift, but if the 2 speed is left intact, you can't have motor brake/reverse. The emaxx tranny is totally different and does need a shifting servo for two speed, but you have motor brake/reverse in both speeds.

[rchotrodz]

well the exv esc can only handle 12 cells but that is fine for me for now and I will be using the e-maxx tranny is it possible to lock it into 2nd gear? or should I keep the 1st and 2nd gear with the shift servo?

[Arct1k]

You can lock into 2nd with a spring or such and then add a servo later to go two speed.

An UBEC is only about $15 and will take some load off the ESC. Castle have a new onle out for low $20's which is very configuable to.

I thought EVX took 14 ok...

[rchotrodz]

is there a photo gallery on this forum? I tried the one that I saw but it did not work I would like to see some peoples pics on how and what they did for the build using the e-maxx tranny and revo chassis...thanks

[Finnster]

Look for Dafni's thread on the Maxx tranny in Revo. It has 16K reads. :) I have one buried somewhere, but I didn't use a 2spd.

I would prolly try to keep the 2spd if you are using titans. It will run cooler, longer and be more fun w/ 1st IMO. Only w/BL is it useless.

I would go with a single st servo and then mount a shifting servo where the other st servo goes. This is what Dafni did IIRC. Making a servo mount should be the trickiest part of this, but not too bad.

A Ubec is to take pressure of the ESCs BEC. The way it steps down voltage creates heat. More step down, more heat. Above ~10V or so I would use a UBEC. The EVX is wierd that it runs two channels (one for ea batt) and BEC draws from just one channel so the step down from 7.2V is not severe.

[Arct1k]

This is my build - I used the old motor mount for a micro servo. Servo mount was easy for a micro servo using a couple of standoffs.

http://www.rc-monster.com/forum/showthread.php?t=7530

[rchotrodz]

ok I am not sure but I seen some e-revos with the e-maxx trans in backwards? and some with it installed like it is in the e-maxx what would be a good way and easier to do but remember I am going to use the stock setup from the e-maxx first then hopefully going brushless if my wallet allows me

[Arct1k]

http://www.rc-monster.com/forum/showthread.php?t=7530

[rchotrodz]

ok so I can mount it either way then right?

yes, as long as you are planning on using a sensorless motor, if it runs backwards , just swap two of the motor wires, otherwise flip the diffs

[rchotrodz]

Arct1k how much did you have to dremmel off of the revo chassis to fit the e-maxx trans also did you have to drill new holes to mount it? and any close up pics of how much you had to dremmel out?