Gearing Suggestion; Hobbywing 3656SD 3400KV

[OkinawaCrawler]

I picked up a Hobbywing combo sensored 3656SD 3400KV motor with SCT Pro ESC. This motor has a 5mm shaft, so I will need to get a new pinion anyway. What is your suggestion for gearing? 3S

Here is the combo, picked it up for $133 shipped:
HobbyWing Xerun SCT Pro C3 3656SD 3400kv Sensored Brushless Combo for 1/10/th & 1/8th Scale SCT & Buggy

Here is more info on the motor:
https://www.hobbywingdirect.com/products/xrm3656sd

[Rjohn929]

Start with a 15t pinion and check temps to see what way you need to go.

[calcagno45]

I would stick with stock 12/64 and run there. My Puller Pro 3500kv is mighty happy at the ratio on 3s.

[Rjohn929]

Too slow. I run a 16t with my 3500xl and wish I had a little more. To each their own I guess.

[nd4spdbh]

Originally Posted by Rjohn929

Too slow. I run a 16t with my 3500xl and wish I had a little more. To each their own I guess.

jezus!!! i cant imagine a bomber that fast.


I run my 1870kv motor on 3s with the trans in OD (flip the top and bottom gears inside so its 28:26 vs stock 26:28 but run the stock 12/64 and its PLENTY fast. I cant imagine needing to go any faster than stock gearing with a 3400kv motor. Hell id look at underdrive front n rear diffs at that point.

Either way OP id stick with the stock 12T pinion (in a 5mm shaft). If you want a little more speed after that, do what i did and flip the internal transmission gears.

[Rjohn929]

I ran a pro4hd 1850kv in a wraith trans a while back but that was on 4s with 16/54. Either I'm doing something wrong or you prefer a slow rig. They are racers not crawlers right?

[maslin]

I ran 13/64 3500kv on 3s for a while, bumped up to a 14t pinion with 2.2/3.0 wheels. Swapped the 2.2 back on and never changed from the 14t pinion. I can see 15t working, you're definitely into it money wise by that point.

Just starting out I'd probably get like 12-15 and see what works. Pinions are cheap, probably the single cheapest thing you can buy.

[Rjohn929]

The most important thing is to check temps. Undergearing and running full throttle is just as bad as overgearing. Start with whatever you have. Check temps and run it to see if your happy with it. If you're not change the pinion and repeat.

[MD ENFORCER]

I was thinking of picking up the same setup. In for results.
Actually looking at
Hobbywing P/n: 81030190

SC-C1
https://www.hobbywingdirect.com/prod...10-sct-combo-1

[OkinawaCrawler]

Originally Posted by MD ENFORCER

I was thinking of picking up the same setup. In for results.
Actually looking at
Hobbywing P/n: 81030190

SC-C1
https://www.hobbywingdirect.com/prod...10-sct-combo-1

You should consider the combo I got, I can't imagine you'd save much getting the sensorless combo.


I will try the stock 12T pinion. From what I read, a lot are still running stock.

[Lanky]

I run 12/64 3500KV 4s for nasty wheelspeed, and 3s for a perfect all around rig

[OkinawaCrawler]

Originally Posted by Lanky

I run 12/64 3500KV 4s for nasty wheelspeed, and 3s for a perfect all around rig

My god. 4s 3500kv must be nuts.

[maslin]

Originally Posted by Lanky

I run 12/64 3500KV 4s for nasty wheelspeed, and 3s for a perfect all around rig

What motor? 58000rpm is a lot. Castle says they're safe to 100,000, but I wouldn't test that out.

[Lanky]

Originally Posted by maslin

What motor? 58000rpm is a lot. Castle says they're safe to 100,000, but I wouldn't test that out.

Holmes puller pro standard... I run the same exact setup on a puller pro 3500 XL in my yeti 16/64....

They're good for 60k.... I do keep my eyes on the bearings.... most rpm I've logged "loaded" is 49k and change....

I am not suggesting this for anyone to do on their builds... and I do assume full responsibility if the motor looses a bearing. I will say under normal use, same gearing, 4s runs cooler.(from my testing). Most temp I've seen is 155 F. That was on the yeti.

[SCREAMER]

A while back, I started running 4s in my IFS Bomber with a Holmes 3500kv Puller Pro standard. It's so nice to have that extra torque and wheelspeed on tap. I do try to drive a little less aggressively but so far there haven't been any issues. My IFS Bomber does have a Wraith trans in it though so it's a bit of apples to oranges. My gearing is 12/56.

As far as OP's original question, I'd say stick with stock gearing, check temps, adjust from there. Swapping a motor, ESC, and changing gearing at the same time can do more harm than good unless you have enough experience with each of those variables to anticipate results fairly accurately.

[OkinawaCrawler]

Originally Posted by SCREAMER

A while back, I started running 4s in my IFS Bomber with a Holmes 3500kv Puller Pro standard. It's so nice to have that extra torque and wheelspeed on tap. I do try to drive a little less aggressively but so far there haven't been any issues. My IFS Bomber does have a Wraith trans in it though so it's a bit of apples to oranges. My gearing is 12/56.

As far as OP's original question, I'd say stick with stock gearing, check temps, adjust from there. Swapping a motor, ESC, and changing gearing at the same time can do more harm than good unless you have enough experience with each of those variables to anticipate results fairly accurately.

Cool! I had this same combo in my yeti with stock gearing and was pretty happy. It's super torquey and you can't beat the price for a quality motor/esc/programmer

[JatoTheRipper]

So did you get the HobbyWing combo yet? It looks like a great combo and that price is tough to pass up!

[OkinawaCrawler]

Originally Posted by JatoTheRipper

So did you get the HobbyWing combo yet? It looks like a great combo and that price is tough to pass up!

Hey Jato, I just bought this a couple days ago and I live in Japan, so it will probably be next week or the week after. I have to build my kit too.

I've had this combo in my Yeti though. The motor is 6mm longer than a standard 540 and has a ton of torque. You can't beat the price for $133 shipped with a 120a esc and programmer. I imagine there is limited stock of this combo though because hobbywing has released some new esc's and motors recently. They also have a 3652 can 3100kv that may be a roc412 equivalent for like $80.

If someone does buy this combo, use fan5 at hobbypartz.com for 5% off.

[OkinawaCrawler]

Hey guys, here are the specs on the motor. Also, here is a link to the motor, if you look at the bottom, you can see the 3652 motor I was talking about and also a 3660 motor. both are around $80

https://www.hobbywingdirect.com/products/xrm3656sd

P/N
Xerun 3656
90100000

KV (no Load) 3400 Kv
POLE 4
LiPo (V) 2-3S
No Load Current (A) 3.80
Max. Output Power* 450W
Max. Amp* 107A
Diameter (mm) 35.8
Length w/o Shaft (mm) 56
Shaft dia. (mm) 5
Shaft length (mm) 18
Weight 210