many questions about a first time electric kit build,Yeti

[8000ft]

Hello, this will be my first electric RC.
I have had 1/8 nitro and 1/5 gas experience only.
I live at 9000 Ft elevation and am tired of the drop in HP due to the thin air.

So with a divorce in the very near future and the selling of the house I will have a bit of spare cash in my pocket and a fair amount of time to myself ...so back into the RC world I go.

This is what I have planned so far and please tell me if I am doing something incorrectly or something(s) that I have missed.

Yeti 1/10 kit
Spektrum DX4C w/ srs4210 RX
HiTec HS-5646WP
Castle Creations BEC
Tekin RX8
Pro4 HD 3500kv
Turnigy nano-tech 5000mah 3s 65-130C

And here come some questions....I have spent more than a dozen hours searching and researching and can not find the answers to these,

1, Is this battery "C" rating overkill for this motor?
2, What is the amp draw of this motor? normal and peak.
3, could I run a 4S?
4, Is there any advantage to running a 2500kv with a bigger than stock pinion OR a 4000kv with a smaller than stock pinion?
5, Is this motor (3500kv) more "powerful" than the stock RTR?

......I haven't seen any videos with the Yeti actually doing wheelies.....

6, What is the RTR top speed and do you think that this will be any faster?

I will be running the 2 speed so I can have a slow crawler and speed too.

7, Is the RX8 that much better than the Mamba Max Pro ($80 difference) and why?
8, What is the difference between the SRS4210 and the SR410 ($50 difference)
9, What servo to use as the 2 speed actuator?
10, I would like a variety of pinion sizes, will any 5mm shaft size work?
11, what is the stock RTR pinion and spur?


If you have read all of this, I thank you very much for your time, Ted.

 

[fr8cture]

1,No that C rating is fine. You can get to low of a C rating but as far as I know there is no such thing as too high. (in Rc batteries atleast)

2, N/A

3,I wouldn't run 4S on this motor. It's only rated for 2S so 3S is as high as I would go myself.

4, All depends what you want but for the yeti is 3000kv seems to be what most people are running

5,Yes although the 3000KV version has the highest RPMs at its rated voltage from Tekin.

6, Stock is high 20s low 30s on 3s. This should be quite a bit more overall power.

7, The RX8 has a bigger Amp rating and has some nice programming features but as far as just working as an ESC I don't see a real benefit.

8, The SRS4210 is a AVC RX basically it tries to improve your driving IMO not worth it just go for the SR410.

9, I just used the stock RTR servo from my Yeti and upgraded the steering servo.

10, With the plastic spur any pinion will work. If you go to a hardened steel spur you will need extra hard RRP pinions for that.

11, Stock is 16/64

I answered the best I could. If I'm wrong someone feel free to correct me.

 

[svt923]

Fr8cture pretty much nailed you questions but I would like to add:

The HS-5646WP servo you listed is pretty weak for a Yeti, it is essentially the same specs as the RTR version's servo which everyone replaces. Something in the 250+ oz of torque range with a response time under .15 is the specs you should be looking for in a servo.

3. If you want to run 4S, then the Tekin Pro4 HD in 2500kv is the way to go. The performance should be similar to the 3500kv on 3S.

7. The advantage the RX8 has is the much higher amp rating like Fr8cture said, this is really beneficial 2 times: when you cram a 1/8 scale motor into a Yeti or when you run a very fast 4 pole motor (like the 4300 Pro4 HD) on 2S. The amp draw is usually too much for a smaller speed controller, that is why the RX8 is the ESC of choice for most 1/8 electric buggy and 4x4 short course racers. The RX8 can also be programmed via an android app on your phone which is pretty cool.

9. Basically, any standard size servo will work as a shift servo since it is not very taxing on the servo. If you have any old servos lying around from your 1/8 scale buggy days, it should work just fine for shifting duties.

 

[trig n tahoe]

I run pro4 hd 3500 on 3s and it rips! Gearing is low 12/64. But can crawl well and float wheelies:mrgreen: I use a MMP. Would love to have RX8 but cant justify it. The mamba works fine. Sorry to hear about divorce, but a new relationship is on the rise already! It just takes a battery and will piss you off just the same! But, you can BEAT it to death if need be!"thumbsup"

 

[8000ft]

Thank you for the responses.

After some more research last night I did find the answer on the RX and it seems like a great option for 2WD race buggies but I don't see any real benefit on a bash truck like the Yeti. (other than the cool factor, I guess).

It looks like I will stick with a 3S capable motor sense I will be swapping batteries with my son's truck/buggy when ever we decide on what kind he wants. (He's 11 and looking for a 4WD buggy with great top speed, I'm thinking that Traxxas may be the best option??)

As for the KV rating, school me on the cost/benefit of running a 2500kv with a bigger than stock pinion OR a 4000kv with a smaller than stock pinion

suggestion on a steering servo?

Is the kit version a plastic or steel spur gear?

Any specific company's to search for pinion's?

I also forgot to include the charger that I'm looking at, the SKYRC iMAX B6AC V2 Dual Power (6Amps, 50Watts)

http://www.amazon.com/dp/B00ND7J38C...TF8&colid=2NMEAM945TQG3&coliid=I11I7H1Q003195

Any opinions??

 

[fr8cture]

Traxxas doesnt make a 4wd buggy as far as I know. I would look at Losi or Associated and maybe Aarma.

For a servo I went with a Protek 150T its the quietest and smoothest servo I've used. It's also very fast.

RTR and Kit both have a plastic spur gear

Pinions I would stick with traxxas and Robinson racing. Most hobby shops carry both of those so its easy to find them.

As for KV ratings I don't know much about them. Only reason I know of for a higher KV is if you run 2S or you are crazy and overvolt it and risk ruining it. Lower KV like the 2500kv if you want more low end but less top end.

 

[8000ft]

I run pro4 hd 3500 on 3s and it rips! Gearing is low 12/64. But can crawl well and float wheelies:mrgreen: I use a MMP. Would love to have RX8 but cant justify it. The mamba works fine. Sorry to hear about divorce, but a new relationship is on the rise already! It just takes a battery and will piss you off just the same! But, you can BEAT it to death if need be!"thumbsup"

Any issues running the 3500kv on 3S?

 

[svt923]

As for the KV rating, school me on the cost/benefit of running a 2500kv with a bigger than stock pinion OR a 4000kv with a smaller than stock pinion

There is a limit on what gearing can do since a 4000kv motor would generate 16+K RPMs than a 2500kv motor on 3S. That is a lot of RPMs to make up through gearing.

Assuming you are running 3S on both motors, you would have to gear up 9 teeth on the pinion using a 2500kv motor to get similar top end as the 4000kv motor on stock gearing. That high of gearing puts a big strain on the motor and would generate a lot of heat.

On the flip side, trying to reduce a motor's speed can cause some problems too. Undergearing too much can cause the ESC to run hot even if the motor isn't getting hot. The 4000kv motor should also eat through your battery faster than a 2500kv motor when geared to give comparable speed to the 2500kv on stock gearing.

 

[8000ft]

Great info, thank you.

Here is my goal, I would like to run the 2 speed transmission and use the low gear for 0-12 mph ( general crawling and slow speed environments like the woods around the house), and use the high gear for everything above ( street, baseball-fields, dessert, jumping, etc...).

Am I trying to do too much?

It sounds like I should go with the 3000kv Pro4HD and play with the spur/pinion combo.

https://drive.google.com/file/d/0B83oSBQhNctYemNlYkxRWmtoR0U/view?usp=sharing

19/56?? or something??

 

[trig n tahoe]

No probs with 3500hd on 3s....... Except the smile hurts my face :mrgreen:

 

[Phaeton]

From my own experience, running the RTR with stock motor and gearing.

2. Amp draw 29 A during full acceleration

6. Speed with a 2s lipo 29 km/h. Will try a 3s lipo another time, but expect it to be just over 40 km/h

Yvo

.

 

[8000ft]

Oh crap, I just realized that the Pro4 HD and RX8 are not waterproof. Any difficulties in proofing them?? I will study some videos tonight when I get home on the subject.

 

[fr8cture]

Conformal coating. You could get a Holmes setup that is already waterproof.