electric revo questions

I just recieve my rollier revo, and i want to convert it to brushless.
I've the mamba max controller, and i plan to run it on 4 or 5 li-po cell flight power.
I I've a Feigao 9L and i want to know if this motor is enough powerfull to push a revo.
But i think to buy a Plettenburg Maxximum.

And most important, is the revo drive train (tranny and diffs) will hold on bruhless power?

Wich modif should i make?

Thank!

David

[BrianG]

The 9L will be strong enough if you keep the 2 speed tranny. The only downside to the 2 speed is that you can't use the motor for braking or reverse.

Other than that, the drivetrain is pretty tough. I've only broken the pins holding the gears to the shafts inside the tranny, but upgrading to the slightly larger Jato outdrive pins fixed that (and a little shaft/gear modding to get them to fit).

I would stick with 4s if using the Mamba Max ESC. It should be able to handle 5s, but IIRC, some people say it acts funny. Besides, 4s is plenty for a 9L.

Brian could you tell me what's your custom 4 spyder diff?? And does this mod bulletproof the tranny or the stock will be fine?
And should i lock it in second gear?

thank's

[BrianG]

Originally Posted by david lamontagn

Brian could you tell me what's your custom 4 spyder diff?? And does this mod bulletproof the tranny or the stock will be fine?
And should i lock it in second gear?

thank's

You mean the custom center diff? I got it from Squee a while back, and now Mike has it so he can take a look and possibly copy it and maybe make it better. The Jato pin mod does make it stronger; I haven't had any trouble since I did it. With the stock pins, I broke a couple. If you are running a 9L, you shouldn't have any problems since it's not quite as torquey.

OK if i understand well, the easy and cheapest way to convert my revo is to take a RcMonster motor mount, put my 9L on it, install a FOC kit on the tranny (because i don't want to have reverse), installl a better pin on the input shaft and lodk the tranny in second gear (i'll want to keep a servo for the break, don't want to break with the motor to drain less current from the batt) and buy a FlightPower 5000mAh, 14.8 volts li-po pack??? That's it??

[suicideneil]

Custom diff: http://www.rc-monster.com/proddetail...rod=rcmflmrvdf

Stock tranny is pretty strong, and the 9L doesnt produce quite as much torque as an XL motor, so it should be fine. If you intend to mainly race, then I would say leave it unlocked, but if you want to bash more, then locking the tranny in 2nd is a good idea (very simple) so you can use the motor for braking+reverse, otherwise you will need to keep the mechanical brakes fitted, and probably disable reverse on the esc since the reverse gears are very weak.

When you say leave it unlock, you want to say to leave the 2 speed fonctional?

[squeeforever]

If the tranny gives you troubles, RRP makes metal gears I do believe.

[BrianG]

If you keep the servo brake and don't want reverse, why not keep the 2 speed? You won't have to do the lock mod then. That will let you run a little more aggressive gearing (like 40/16) to give you good top speed while first gear will help with take-off power. Actually, the Revo will probably run better like this since your gearing matches the motor.

If you have the tranny open anyway to do the FOC, you might as well do the pin mod; just prepare for drilling a slightly larger hole in the shafts since they are steel (high speed and light pressure). You'll also want to slightly enlarge the hole in the gears otherwise the slightly larger diameter of the pins may crack it if you try to jam those Jato pins in there. But I think the stock pins should hold up with that motor, but don't quote me on that.

So, this is what I would do:
- RCM motor mount
- A few Jato outdrive pins. Not sure if you can find just the pins...
- FOC
- Whatever battery you want (4s is good)

OK Brian, i thaink to keep the two speed, but if i plan to upgrade motor in near futur, like an 9XL or a Plattenburg BigMaxximum, is the two speed gear will hold on the extra power???
Because on my Jato conversion, with a Feigao 380c 6L on 3 cells, each time that the tranny was shifting into second gear, the second gear exploded in the tranny!!!!

But anyway, with a 9XL or a Plett motor, the extra power will not justify the two speed anyway, right?

And for li-po, don't want wich to choose, i think to the FlightPower 4900mAh, 4 cells, but they cost $80.00CAD more than the MaxAmps HV5000, 4cells.

But somebody here on the forum tell me that the extra $$ of the FlightPower realy worth the money, that's right???

And the i think to the 5 cells too, but thinking that 5 cells will be too violent on the tranny and diff gear.

I'll use this truck only for bashing, with paddle on it, because for racing i've a brushless crt.5.

[BrianG]

Well, if you definitely plan to go to an XL in the future, then maybe locking it may be a good idea. But, you can always do that in the future. TBH: I've never run the 2 speed on BL so I'm not sure how well it'll hold up. Your experience with the Jato makes me wonder now. Hmm. Well, if you do lock into second, I would run pretty modest gearing, like 12-14T pinion with the 40T spur. Otherwise, the 9L/ESC/battery might be working too hard and heat up.

It is said that the FlightPower cells hold their voltage under load quite a bit better under heavy current load than other less expensive cells. This will translate into less heat generated by the lipo pack. If lipos get too much above 130*F, they could go bad. If you wanted to use cheaper cells, you could go with a motor with higher turns (lower kv) and run 5s or more, but you'd have to use an ESC capable of that voltage. Higher voltage on a lower kv motor pulls less current yet still generates just as much power as a lower voltage but high current setup.

Is the MM esc is a capable unit to power a heavy truck like the revo, or should i think to buy something better?,, I've take a look on the MGM controller but it's alot of $$$ for a controller.

You say that if i keep the two speed, gear it 16/40 and if i lock into secont, 12-14/40 did the job?

I've a 13, mod1 here, and a 18, so the 13 for the lock option and the 18 for the two speed option??

But i think that i'll order a 9XL right now. But on 4cells, is i'am better with the 7XL?

Excuse me Brian, i know i ask alot of question, but before to start a big $$$ conversion, i want to be certain of what i did...!

[zeropointbug]

The MM is probably the most used controller for these trucks, GREAT buy for running a budget setup with Feigao, and they run great with Lehners.

[BrianG]

Like ZPB said; a lot of people use the MM ESC. After all, it is capable of 100A and 4s. If you want to go with higher powered setup, a higher current and/or higher voltage ESC would be needed. The MM is definitely the best bang for the buck.

That gearing looks about right. I would stick to the 40T spur for those gears and that motor. If upgrading to an XL, it would be cheaper to pick up different spurs than pinions if you need to tweak the ratios.

The 7XL is certainly faster, but can pull a very healthy amount of current. The MM is good, but that may be too much for it. IMO, I would stick with a 9XL or maybe an 8XL at the lowest.