20T pinion on a Yeti?

[Sactown_Summit]

I did a search and read a few posts that seemed to indicate a few people were having good luck with their stock electronics on 2S but using a 20T pinion? Is this indeed the case? Any feed back to direct experience with this setup would be appreciated. I love the torque out of the stock power system on 2s, but I am looking to get a little more top end speed for some desert style running.

Thanks in advance for any personal account feedback given.

[Powerman]

I am running the 20t on 3s. I added a cooling fan to the motor and esc as well as updated the firmware. Should be fine on 2s as well. Just check your temps as you should anyways. I am also using a moderately high C rated battery. SPC 3s 6500mah 65c.
Since i have been doing this my motor temp has been roughly 120degf to 130degf on 75deg days. ESC has been averaging 110 to 120degf. Top speed in the yard using a Garmin Forerunner as a speedo has been 41mph on a fresh pack. Its not Slash 4x4 fast. But not bad for the weight of the yeti.
Good Luck.

[Sactown_Summit]

Thanks for the feedback.

That is actually great speed for the Yeti. I obviously won't see that on 2s but good to know the electronics can handle the 3s and 20T combo. I have a fan for both the motor and ESC so if temps are running to high I can throw those on as well to assist.

[Powerman]

I want to check the speed against another GPS and for a longer distance. It didnt look that fast. But my temp gun is good for sure. I am not sure how long the AE-3 will hold up to that. But so far its doing fine. Just dont try to crawl with that tall of gearing unless you upgrade to a better ESC.

[Sactown_Summit]

Yeah I agree. Even though I did the firmware update, I was able to thermal the ESC on the stock gearing doing some crawling. And that was on 2s too. Now it was in the 90's outside when I was crawling, but the stock ESC wasn't digging it. Saving up for a sensored system now. Will save the 20T pinion for that.

[binaryterror]

Crawling on the stock gearing will get anything hot. It's more a race/bash gearing stock.

If you want to crawl, you'll want a 12T or maybe 14T max.

[Sactown_Summit]

Originally Posted by binaryterror

Crawling on the stock gearing will get anything hot. It's more a race/bash gearing stock.

If you want to crawl, you'll want a 12T or maybe 14T max.

That's a good call. I quickly learned on the stock gearing it's not really crawling I do, it's more like rock hopping or bouncing. Have to keep the momentum going a little and keep pushing through along over bounce over the top of the rocks.

To truly crawl your right will have to go down to probably 12T pinion.

[Powerman]

I need to mention the fact that I am running smaller tires as well. Using the PL Badlands on stock wheels. They are about 1/2" smaller in diameter than the BFG Krawlers. I am looking at the Yeti as more of a SC truck so I am building the truck as being just that. With the 20/64 gearing the motor is not working at all. I am considering the MMP/3800kv on 3s to see if I can get a little more gitty up out of it. Unfortunately its in my CW Slice that I am very fond of. I cant bring myself to rob parts off of it.

[Sactown_Summit]

Yeah I think you have a good concept taking the Yeti more to the sc truck side of things. There is no wrong or right purpose, but for me I am looking for my Yeti to do a little of everything and I understand in doing that it won't do one thing great. For me down the line I am probably going to stay 2s, and go with a sensored 3500kv system to get more speed out of 2s with more gearing options, but also have the ability to crawl. That would leave me very satisfied.