MMM Combo question
 

Hi all,

Picked up the 2200kv MMM Combo from Tower hobbies last week. Couldn't go past the price lol. $299USD less $50USD with a voucher they'd spammed me with sealed the deal.

Anyway, just a question with regard to the included 19T pinion. They say the 2200kv motor is recommend for 6S. Wouldn't the 19T pinion make the gearing WAY too high?

Bigger pinion = higher top speed/lower acceleration correct? At 2200kv, I would have thought that the pinion was too large, and in order to keep the heat and amp draw down, something like a 13-14t pinion would be required?

22.2v x 2200kv = 48840 unloaded RPM.

Anyway, was just wondering because I have a 1600kv 80mm Medusa on backorder, and all the advice I got given was that the 1600kv was the best on 6S, and that 2200kv would cause rather high amp draw and extra heat.

It's up to you to use the included 19T pinion. Keep in mind that the 19T can be used with sensibly depending on the spur you'll be using. For example, if I use the combo on my gmaxx, I'll be using a 51T spur with that 19T pinion. By the way, I'm running my gmaxx with 51/20 spur/pinion on 6S with a TeknoRC Neu 1515 1Y which is similar to the CC combo. I never had any heat issue with this setup.

Use BrianG's speed calculator to get an estimate of your setup.

Oh yeah, what vehicle are you going to run this with?

Kyosho Inferno ST-RR for now, but a Savage X SS or XL is on the books for conversion in the very near future.

I've only got the stock 50T spur, but I'll be ordering the 52T in the next few days.

What sort of amps are you pulling with your Gmax and which LiPos are you using, if you don't mind my asking? :D

I don't have an eagle tree so I can't tell you how many amps I'm pulling.

Anyway, I just completed an ST-RR conversion last month. It's running with the TeknoRC Neu 1515 1Y (I took it from the Gmaxx) on 5S Neu 5000mah(2s and 3s in series) with an MMM V3. I'm using the stock 50T spur with a 16T pinion. Highest temps I got were: Motor-130F, ESC-102F, Batteries-100F. Air temp was about 58-60F.

Here's a couple of pics:
http://i256.photobucket.com/albums/h...Picture038.jpg

http://i256.photobucket.com/albums/h...Picture036.jpg

Man those are nice temps... It must just be my crapola Feigao motor that gets hot doing a little bit of work lol.

Anyway here's a couple of pics of mine, with the new RCM battery mount. I currently run A123s, either 4s2p or 7s1p.

http://i157.photobucket.com/albums/t...R/IMG_7590.jpg


http://i157.photobucket.com/albums/t...R/IMG_7592.jpg


I will probably be swapping to LiPos as soon as I can decide whether to purchase 4x3s packs, or 2x6s packs, and whether to go 4000mah to keep the weight down, or 5000mah for longer run times. Seeing as how I only need to get between 15-20min, I might actually go for something like 3300mah packs to further reduce some weight.

Also considering ditching the mech brakes. It seems to be a bit of a waste of space, and I really don't notice the difference between having brake bias and not so its just extra weight.

How heavy are your packs?

I believe the pinion included with the combos is 18t, but it is 32 pitch. Your STRR (as well as the savage) I think is mod1, so you will not be able to use the included pinion.

I thought the pinions included WERE mod1?

It's 32P, note the teeth size compared to the 5mm hole.
Anyway, it's the most beautiful pinion I've ever seen, I may put it on my key chain.... :rofl:

http://bbs.rcfans.com/attachments/da...WKhO22hPez.jpg