Axial Yeti Speed

[Hedsic]

I am a noob to this so please bare with me and don't flame on me to hard. I just got my Yeti RTR the other day. I had planned to get 3s Lipos but everyone told me to stick to 2s since I'm a beginner so I picked up some 2s batteries and a charger.

I show that the Yeti is listed at going 30+mph. I felt like mine seemed really slow. Granted I get it's not a street racer but it still felt slower than I expected. For the fun of it I raced it down the road with my son using his Dromida brushed DB4.18 and the Dromida actually beat it just slightly in the long run (but the Yeti had way more torque). The GPS speed recorder listed the Yeti at 15mph max speed.

We did pop in a 3s battery and it's top speed hit 25mph which felt way closer to what I was expecting.

Is that pretty standard for it to be that slow on a 2s lipo out of the box? I'm not complaining at all because so far I love this thing and I find myself no longer looking at Jeep parts to buy and spend my day looking at modifications for the RC truck instead. Just wanted to know if 15mph on a 2s lipo seemed about right or if maybe something was wrong out of the box.

Any help would be appreciated, Thank you so much!

[micro racer]

Sounds about right. Remember, the SCORE chassis and electronics are no different from the regular Yeti...

[gbean]

Typical advertising.. Add 20% to the specs, you'll sell enough to cover any legal costs you (probably won't) incur.

[DenisLM]

probably the 30+ means with pinion change... traxxas do it since always...

[gbean]

Traxxas is the worst at this.

[DeviledEggs]

Originally Posted by micro racer

Sounds about right. Remember, the SCORE chassis and electronics are no different from the regular Yeti...

The score has smaller tires than the normal yeti so with the same gearing the TT will be slower...

[Ty1330]

My 3800 in the Rock Racer is pretty quick, 2s is nothing all that exciting but 3s is more than enough giddy up with that truck. My TT runs the rtr motor and esc and on 3s it was still pretty darn slow. I ended up bumping the pinion to a 22t and its pretty much at the point of being about as fast as that chassis needs to go (somewhere around the low to mid 30mph range). I personally never saw any 30mph claims on the boxes of any Yeti's I've seen.

[gbean]

Originally Posted by DeviledEggs

The score has smaller tires than the normal yeti so with the same gearing the TT will be slower...

Should means those stock electronics should last a bit longer....

[micro racer]

Originally Posted by DeviledEggs

The score has smaller tires than the normal yeti so with the same gearing the TT will be slower...

If you want to get technical, then yes, the SCORE will be a little slower than the regular Yeti. However, the difference is so minimal that only a tooth or two higher on the pinion would bring them to the same speed.

One could also argue that with equal gearing, the SCORE will be quicker off the line because of less rotating mass.

My point was that the SCORE is still a "rock-racing" chassis and is not designed for all out speed, not that the two Yetis are exactly the same...

[8000ft]

To answer your question, yes it all comes down to voltage and RPM's of the motor.
The motor is a 3800 kV so this means that it will turn 3800 RPM's for each volt supplied.

At a max charge of 4.2 volts per cell;

with 2S (8.4V) you will get 31,920 RPM
with 3S (12.6V) you will get 47,880 RPM

You can switch out the gear on the motor for a larger one, 17, 18, 19 OR put on a smaller spur gear 56,58,60 and your speed will increase.

I have tried a 19/54 on 3S and it is really fast but completely uncontrollable and flips at the slightest turn of the wheel.

I can't remember for sure but I think that I am running something in the middle like 17/60 on 3S and it is perfect.

I do feel your pain though, when I set up next to my sons Slash it's a totally humbling experience when he hits the trigger and is gone in a puff of dust. (his will run in the 50's with the current gearing).

[snapon boy]

Make sure you get a temp gun so you can check you motor and esc Temps when changing spur and pinions and also using 3s or 4s battles etc. Don't exceed 160. You may know this if so sorry.

Sent from my SM-T350 using Tapatalk

[tooltimenova]

Axial Racing - Yeti


I run a 21t pinion in mine when it is set up with the Score tires and body and go back to the 16t when i run regular 2.2 tires and the VW body. Axial has a blog about it (link above) and it makes sense with the diameter in tire change.

[8000ft]

gear ratios,
21/64 =3.05 Axial example for their speed run using a 3150kV w/3S (32.5mph)
17/60 =3.53, my current setup using a 3500kV w/3S
19/56 =2.95, my highest gearing option 3500kV w/3S (way uncontrollable)

their top RPM 39,690
my top RPM 44,100

my top RPM is roughly 10% so with their set up I should run about 35 MPH but my set up is slightly taller so I'm am guessing that I should top out in the high 30's and my tallest gearing would be in the low/mid 40's.

I am running a Vant battery 6600 maH, 3S

I don't know if this info does anything for you.

[Dbdynsty25]

I tried both the 21/64 and the 17/56 and ultimately I went with the 21/64 as the speed is pretty similar on 3S. Plus it's a lot easier to replace the pinion.

[8000ft]

pretty good guess on my part. I just GPS's it with my old phone and I wish it had a decimal readout but in whole numbers it was a solid 34 MPH at 12.6 volts three tests in a row.

31 MPH at 11.4 volts