gearing cuestion

[jalodo56]

hello
I have a kyosho kanai II brushless, with medusa 2200kv 50mm, Mamba max with ubec, 4s zhippi 5000mha 20c-30c. I have a 46t spur and 13t, 17t and 19t pinions. Which is the best configuration? Can I kill a nitro? I can buy an another pinion, but I prefer use my pinions.
Regards

[suicideneil]

Nitro killing is easy with BL, no worries there.

What are the diff ratios (front/rear) or the ring and pinion tooth counts, and the tire diameter.

When you know that much, you can then use the gearing calc to fine tune your gearing for your desired speed- 40-45mph should be plenty..

[jalodo56]

the diff ratios are 43/13(front and rear) the tire diameter is 4.5
regards

[suicideneil]

46/13 comes out at 36mph.
46/17 = 48mph
46/19 = 54mph.

I think a 13-14 tooth pinion will give you plenty of speed for racing with the 46t spur, but for nitro killing I woud think a 60mm motor might be better for more torque to allow the taller gearing work better; 48mph isnt too bad, but 54mph is a little much for a 50mm motor in a... 7lb buggy? I dunno how much it weighs or its size.

[jalodo56]

ok, thanks, My buggy weight is 7.9lbs with all, batteries, motor, esc............... then Can I kill nitros?
I want to go as the nitros or a bit more fast.
Regards

[suicideneil]

60mm Medusa would be fine for that, more than enough power to kill nitro buggies- might want to look into a few more spurs though to allow fine tuning of the gearing ( a few teeth larger if possible).

[jalodo56]

Ok, but I want use the 50mm 2200kv, with 13/46 all run cool, with 17/46 in 5 minutes of use the motor run cool and the esc a few hot, but I think that the 15/46 is the best option.

[suicideneil]

If you've already done the experimenting, then you also know what works/runs cool and what doesnt, so no real need to ask for advice. All you really need to know:

hot motor + cool esc + cool batts = undergeared.
cool motor + hot esc + hot batts = over geared.
Hot everything = way over geared.
Warm/cool everything = just right.

Like I said, a slightly larger spur gear would be good so you can use the larger pinions without being overgeared quite so much- hence the hot esc with 17/46. That said, I dont know if a larger spur is an option, so 15/46 sounds like it will be a happy medium.

...hmm 3.6kg buggy...

...i am running a 4.4 monster, HFX BrimStone, with the same CD...46 / 16 and the motor got hot so appaently i am undergeared? Only the motor really got hot...batteries were cool and the MMM was warm; the fan came on...

...The motorplate needs some holes and the heatsinks need to be taller too...Unfortunately i just ordered a 12 and a 14 pinion when i ACTUALLY should be going HIGHER than 16?