ImpalaPolicePack

hi guys,

i just bought a e-maxx for this winter.
i bought it because its the waterproof model and i dont feel like messing with nitro engines in the cold again. i had a great time last winter but its been expensive replacing servos, hump packs, bearings and i dont feel its good for the engine to go from 250F to 185F in a second because of a splash of snow.
(and i had put everything in ballons and dryed/oiled bearings after use)

so my questions are:

1. i paid 240$cnd for it, and still has original body wich is in good shape. the only thing i see that i have to change is a cv boot on a front axle. did i paid too much ?

2. i often see people talking about model numbers, how do i know wich one i have ?


thanks for your time !

Impala

cummins driver

My Feedback: (31)

Thats a very clean looking truck. Im not sure how that converts to U.S. dollars, but the truck looks really clean.

As for the model. That is a 3905.

3906- Old model, black chassis, AM Radio, 2 speed transmission
3905- first real revision of the e-maxx. New chassis, stronger 1 speed transmission, Brushed motors, AM Radio, Much bigger driveshafts
New 3905?- Same as original 3905, just a 2.4 radio instead
3908- Brushless ESC/Motor setup, 2.4 radio, everything else same as 3905

So, yours has the AM radio, brushed system, and new chassis, which makes it a 3905. My father in law has the same truck, and he loves it. Run times are good, and he hasnt had any problems from it yet. Its a fun truck to drive[8D]

Eric

Dale Gribble

My Feedback: (4)

You have the latest E-Maxx version, the 3905. It looks really clean, and I think you got a good deal.

I hear ya on the Nitro v. electric. I am still a die hard nitro guy, but I SURE love the each of the modern electrical systems and trucks.

Time to get to work now and make it look like this-

ImpalaPolicePack

haha thanks for the quick replys, and i dont think i will make it look as good as yours ! it will be for when i go out of fuel and a winter beater.
240$cnd is about 210-215$us

ill see what breaks first and fix/upgrade from there, probably with RPM since it will run at cold temps and stock plastic gets brittle.

thanks again !

Impala

ImpalaPolicePack

ok i ran it today for the first time with fully charged batts(when i bought it i tryed it with almost dead batts)

first impressions : it sucks !

bottoms out too easily, tires are kinda hard, slow as hell, slipper slipping big time,

so ill be looking at paddles for this winter and keep the stock ones for dirt/grass
tomorow ill mess with the slipper adjustment
anyone have innexpensive spring set stiffer then stock to suggest ?
and speed... 2 batts, 2 motors, and slower then a oldman electric wheelchair ! since i ran it in water/rain the esc and motors only got warm, but can i gear it bigger without heat issues ?


thanks for your time !

Impala

cummins driver

My Feedback: (31)

They arent speed demons, but if you know what to expect from a brushed R/C truck, then it shouldnt be that bad. Dont gear it up from stock, or the titans will live an even shorter life than normal. The stock tires are kind of hard. The springs are soft in stock form. Its not bad for climbing like that. Just put some preload spacers on the shocks.

What kind of batteries were you running? Do you know what kind of shape they are in and when they were last used? 6 or 7 cell?

Eric

Dale Gribble

My Feedback: (4)

I have seen a 3905 brand new out of the box and it is surprisingly quick. Your batteries must not be giving the juice the truck needs to scoot. Maybe cycle the batteries a few times and see if you can squeeze some more out of them.

ImpalaPolicePack

the truck came with 2 stock 7 cell batterys(3300mHa if i remember right)
it also came with 2 7 cell duratrax batterys. i used those for yesterdays testing.

i dont know how much time they sat before i charged them but i will give them a couple cycle on my charger.

im not really into climbing but more into jumping so when that plastic chasis slaps the ground my heart stops !
ill look at preload spacers at my LHS today.


the esc is max 16.8v
these batts are 8.4v - if i go lipo i cant run 3s
so 2s lipo is 7.4 - exept maybe better runtime, it will not be more powerfull ?

Dale Gribble

My Feedback: (4)

Good lipos provide a pretty significant power difference because they can sustain a larger current draw over their nimh counterparts with a lower voltage drop for a longer period. If you go with 2 decent 2S 7.4v lipos, you will most definitely see an improvement. It's not necessarily about the pack's voltage as it is the lower voltage drop and higher sustained output under load.

2 good 2S lipos will outperform average 8.4v nimhs, not to mention the weight savings.

Otherwise, ya, cycle those puppies a few times and the truck should wake up.

ImpalaPolicePack

thanks for the quick reply !

ImpalaPolicePack

ok first of all, i just noticed that i have the aluminum big bore shocks from traxxas(worth 90$+tax at my LHS)
so it still sucks , but a little bit less !

i also looked to see why the shocks were acting like this.
once removed from the truck they are hard and compress/decompress nicely so i looked at the ball joints and the upper ones are hard to move.

i tryed the shearch but didnt find any thing usefull. i want to know what i can do to make the ball joints move freely.

i tryed greasing them but it doesnt change anything.


thanks again !

Impala

Dale Gribble

My Feedback: (4)

The ball ends are secured to the a-arm with an allen headed ball mount screw. Look through the wheel (or take the tire off) See the larger hollow allen headed screw on the upper and lower a-arms? Those are what adjust the tension from the a-arm ball ends to the steering knuckle. You can loosen those to free up travel. If you loosen them too much, you will get slop. The key is to have those screws snug enough so the arms travel freely up and down.

These are what I am talking about-



Adjust those and a freely moving suspension you will get.

ImpalaPolicePack

awsome !

you have the right answer to every of my questions and i like it !

ImpalaPolicePack

fixed my binding suspension today, now im trying to see how i could improve steering response.

i didnt disasemble the servo saver yet but it doesnt look adjustable. i looked a bit on internet and people talk about the pro-line kit or the kimbroght(speeling?)

anybody have info on the servo savers upgrade ?

Dale Gribble

My Feedback: (4)

The new 3905 EMaxx does have an integrated servo saver that was much better than the previous model but I can't remember if it is adjustable... It is a good servo saver though and the steering response should be sufficient unless something is broken or sticky. Do you have the dual rate steering on your transmitter set to max?

Look at this picture. The side with the spring is a servo saver.

ImpalaPolicePack

thats the saver i have, servos moves but the wheels stays straight. the saver absorbs all the force from the servos.

i removed it this morning and its not adjustable. but i will try to put 2-3 washers on top of the assembly before putting the screw back in

ImpalaPolicePack

ok the steering response is better now with a couple washers under the saver.

now i have another problem, i went out to test the new steering and after about 5-10 mins the truck came to a stop.
i got close and i could see smoke comming from 1 of the motors. after inspection, one the the little copper bars that hold the brushes broke and fell inside the motor.

i want to keep it waterproof for this winter. after reading a bit i found something interesting, a single titan 775 running on my stock EXV2 4 output wires , keeping everything waterproof.
they say the runtime increase and the torque double. the speed stays about the same. that would satisfy me.

id like to hear from people that have done it.

thanks for your time !


Impala

ImpalaPolicePack

anyone ?[]

Dale Gribble

My Feedback: (4)

Based on what I read, that motor will not bolt directly to the stock E-Maxx motor plate without some modification. You could go that route or with a new pair of the Titan 550s. It will cost the same. I don't think you can go wrong either way honestly.

Dale

ImpalaPolicePack

thanks dale, i dont mind modding the motor plate, and since ill be running in snow i will use nimh batts. runtime kinda sucks with 4500mah batts on 2 motor.

im hoping that with a single 775 the runtime will increase a bit.