Which Medusa 70/80 series for a Converted Revo on 4/5s
 

I can decide on which Medusa 70-80mm motor for my new Revo conversion....I will be using 4 and 5s...mostly 5s. Any thoughts?:mdr:

2000kv, gear 'normally' for 4s, and down a tiny bit for 5s. Thats what I reckons at any rate.

I was figuring on as much...how about the 70 mm can vs. the 80?

I've had good luck with the 60,so would assume the 70 would be fine.But with the 80 being so close in price........

Thats the one thats been making my brain hurt- you either have to choose 2000kv which I think is a little high for 5s lipo, or 1600kv which I think may be a little low for 5s, and definately too low for 4s really. I would however go for the 1600kv 80mm motor on 5s lipo as the bigger motor can pull taller gearing to get you your desired speed, just means you need good batteries for the higher load.

Thats the theory anway....

On 5s w/the 1600kv motor, it will be quick, just not a speed demon w/the 70mm can. I am running 20c 4k 5s ProTek batts, if it makes a difference.

80mm 2000kv on 5S is good.

I'm running the 70mm 2000kv in my buggy on 5S & it's a rocket.

IMO, 5S x 2000kv is 37,000rpm & a perfect comparison to a nitro's 38-40k rpm.

Run it on 1-2 teeth above your stock clutchbell.

Would the 80mm can be better for nothing else other than the weight of the truck. It should give it more torque, but, the demand on the batts. would be greater?

Mozzy you asshole, now you've got me doubting my own rational again... :lol:

I believe so. That I'm an asshole that is! :lol:

That's why I chose the slightly higher kv & 80mm for my LST. The 80 will have more torque than the 60 & 70mm cans of the same kv.

Now, what about a heat sink for the 80mm can...any ideas?

Mike's RC Monster heatsinks fit well, but, on the 80mm they stop just short of the wires which is ok.

The 70mm is shorter than RCM heatsink.

I heard that there's a little fan unit that goes onto the back of the motor to draw air through it, but, I've never seen it.

See the flat spot on the shaft?

http://i55.photobucket.com/albums/g1...CMheatsink.jpg

I have a heat sink on a 9xl now, so it should work on the 80 mm correct...

Sure will & look something like this.

http://i55.photobucket.com/albums/g1...CMheatsink.jpg

novak hv motor heat sink direct fit with my 70mm medusa :)

Mike told me the 74mm XL clamp with the motor spacer is a perfect fit on the 70mm.

In a Revo I'd stick to the 70mm, the 80mm has some insane power and will shred your truck.

I have the 70-2000Kv with 5s on my revo conversion. The 70mm Medusa sits close to the rear upper arm so the 80 might give you some fitment issues. It runs cool. In fact, it runs cooler than my TeknoRC Neu because of the cooling holes in the rear of the motor.

http://i256.photobucket.com/albums/h...Picture092.jpg

Thanks for the pic......any issues w/dirt getting into the rear end of the motor w/the holes

So far none but I'll be installing a dust guard on it before my next run.

Nice install George- got a vid of that setup in action? Also, weight & comparison to setup with a feigao or neu etc?

I thought I had my setup planned out, but now Im just back to square one again... :lol:

Neil, I don't have a video of it yet. It's been cold and windy here lately so no time for any runs at the track. However, I did run both the TeknoRC Neu-powered ST RR on 5S and the revo/medusa on 5S 3 weeks ago. Both were using an MMM V3. I like the power and smoothnes of the Neu than the medusa. I know the medusa is a 2000Kv motor compared to the 1515 1Y 2200Kv on the kyosho so there is a very noticeable difference between the two. I'll be swapping motors in a few weeks and do another comparison run. Bottom line, I like the Neu better.

Kyosho ST RR:
RTR with 5S 6000mah Polyquest lipos, TeknoRC Neu 1515 1Y, CF MTR on LPR dish wheels.
10.23 lbs = 4.65 kgs

I still have to weigh the revo.

Edit:
Here are my temps on the Kyosho:
ST-RR
50/15, 5S

ESC – 104
Motor – 131
Batteries – 100


ST-RR
50/16, 5S

ESC – 112
Motor – 170
Batteries – 104


I'll run a 46/16 spur/pinion next time.

I will be awaiting your findings....I also considered putting a Neu 1515 in it, but I really didn't want to drop another $240+- on another motor...I own 2 other Neu motors, a 1509 3300kv for my crt.5 and a 1512 1.5YF for my Mugen buggy and love them both. As w/ many these days, money is a lot tighter and if I can save almost a $100- on a motor, I have to consider it unless the Neu is that much better that it is really worth the difference.

Are you keeping the 2-speed? If so, the 60 will be great. The 2-speed allows great low end power and good top speed from a smaller motor. We typically run Neu 1509's in our Revo's and I've had success racing one with a 50mm 2200kv Medusa on 4s. Plus, with the smaller motor you'll be able to get longer run times. Mike's L heatsink fits great on the 60mm's as well.