Kokam 3200 SHD Lipo

[lipomax]

If it wasn't for the amp draw possibly damaging the Lipos, I would have easily geared taller - there was as much acceleration as a 3100XL on 12 cells and geared with like a 12 tooth pinion!!!! The XL3100 on 12 cells and geared 20/66 could hit 45 mph, but no way could it flip backwards in second gear.

[RC-Monster Mike]

Did you get any extended run times with this setup? I bet the little motor works up a sweat putting out that much power. I have experienced the same concept. The little motors put out plenty of power! The problem is when racing, the heat buildup becomes an issue (I fried a basic 3100 in a race - burnt the windings!). The higher voltage should minimize the heat, but that would still be a concern for me.

[lipomax]

I did run the Basic 2700 with the 22.2 volts for an extended period of time - but it's COLD here in Chicago and I was running it in first gear the whole time. I was kicking up MAJOR snow rooster tails. The flying snow also kept the motor cool. At the end of 10 minutes, nothing was hot - but the batteries - 110 degrees F.

For racing purposes, I would NOT recommend a small motor. You need surface area and cooling fins and maybe even a fan. In addition, you want to keep the motor in the most efficient RPM range - about 30-40 k rpm. AT 22.2 volts, I think the basic XL1600 or maybe the XL2000 is better suited for long races. BTW, I think I ran for a good 10-15 minutes and I only used 1/2 the capacity!!!

[RC-Monster Mike]

We are on the same page. I run heat sinks and fans during the hot summer months. Racing is pretty hard on things. I haven't raced a basic sized motor in a while for this reason. Even the xl3100 gets pretty hot on 12 cells. I am looking forward to this season with some Lipos and hopefully cooler running with higher voltage. I have been playing with the Lipos, but mostly in my TC, as I had the same packs you did (2000mah, 15c Kokams) and did not want to push them too hard in my e-maxx. I ran them in series with an xl2400 for a good 8 minutes screwing around the house with no ill effects (and only drained 1300mah from the packs), but never raced them. I will race the 3200s, though!:)

[RC-Monster Mike]

I have had great luck with the Feigao "L" cans too. They are big enough to run pretty cool.

[lipomax]

When I run high voltage Lipo, the motors definitely stay cooler than with lower volts and NiMH. A basic 5300 with 6 cells get HOT during a 5 minute race. A Basic 2700 with 14.8 cells gets nowhere near as hot, nor does the controller get hot, and to boot, there is MUCH more power too.

When you ran those 15C 2000s, you were probably pulling about 60 amp spikes in first gear if you geared for 35 mph. Probably not damage those, but could if ran hard.

I used to run my 15C 2000s in my TC for 10 minutes at a time geared for 35 mph. I would pull amp spikes of around 40 amps but occasionally would end up swelling a cell here or there. Constantly going over the max rating will harm cells. BTW, for TC, I would rather use the U Force - the parameters can be set for drag brake, etc. First thing I noticed when I went for the 12.97fwe to the U Force 75 was that it was more driveable with a little drag - or maybe it was the car?

[lipomax]

Yeah, just got a Feigao 10L which is similar in specs to the XL2400. I got it with 1/8" shaft so I don't have to get special pinions and it holds up just fine for me. Plenty of torque too. But because their max is at 50,000 instead of 65,000, I tend not to use them in speed runs. In speed runs, I max out the motor and batteries. W/O a doubt the BEST value for motors out there. For 80 bucks you get a Neo brushless motor that can peak out around 2HP for brief moments, has no maintenance... Too bad nice controllers cost so much money.

[RC-Monster Mike]

I should have some MGM controllers soon. They are nicely priced and seem to be liked by some others. I hope to test them this week coming. I am getting the 60 amp and 80 amp 12 cell car controllers for now (should work nicely with the 1/10 vehicles and eliminate the rx pack needed in the warrior line). They have some higher cell count car controllers coming soon, too (and higher amp rated), and they are priced quite nicely. Hopefully they will work out.

I have pushed the Feigaos past their rpm limits (I'm sure you have, too!) without any ill effects, but I don't often do speed runs and tend to keep the motors working in the mid 40k rpm range (seems to be where they are happy). The Feigaos are a great motor for the money without question.

[lipomax]

Believe it or not, most of my running with Brushless is between 30-40 K. Rarely above 40K. Back to this thread, I got those packs in the mail today and first thing I notice is like the extra 6 inches of wiring - so I'm gonna have to cut open this pack and resolder the wire so it's only 3 inches long. Too bad - I only have clear heat shrink. Funny thing is that this battery looks IDENTICAL to my 15C 2000 mah Kokam packs but just longer. I wonder if those 15C 2000 mah are actually 20C but underrated at the time? Maybe...

They weigh a lot though and considerably larger than Polyquest. Thicker and wider. I guess you have a weight penalty for lower internal resistance. It weighs about the same as a 14.8 volt 3100 Polyquest, but is only 11.1 volts. However, max continuous power is 700 watts (minus voltage drop) vs. 550 watts (minus voltage drop) so oz per oz, it'll pump out more power, but less energy than the Polyquest packs. Good for high power shorter races, bad for 30 minute endurance racing. Good for drag racing too - 700 watts continuous from 10 oz is better than GP3300's. A 5 cell GP3300 cannot give out 700 watts CONTINUOUS. I'm thinking this pack alone will peak out at around 1000 watts - when the weather gets better, tests will show this soon enough.

[lipomax]

I've finally got a chance to run those Kokams in my TC4 last night. I've tried all sorts of combinations of motors and gearing. Tried the Twist 4200, C40 12s, basic 2100. Tried different ratios and different voltages. For my track (small indoor carpet track), I find that the ideal setup is C40 12s, geared 10:1 FDR using rubber tires Sorex 20. Funny thing is that 14.8 volts had too much power an dwas uncontrollabe so 11.1 volts was the better setup. Under 11.1, the max speed is only 30 mph, but the stock guys are running about high 20's and that top speed is only reached ONCE on the back straightaway. Motor RPM is almost 40,000. Comparing the Polyquest 3100 11.1 volt pack which weighs only 7 ounces vs. the Kokam 3200 11.1 which is 10 ounces, they were pretty much idential in performance. Actually, the Polyquest being lighter, transitioned better. So, for small indoor carpet tracks gearing a "slow" motor, I don't think you need 20C high discharge packs. The higher discharge packs weigh more for the same energy. I prefer the polyquest in my TC4.

After 20-25 minutes of NONSTOP running, motor temp was at 160 degrees F, controller 130 and batteries were at 105. That's pretty good running temps. I ran a total of 2 3200 packs, 1 3100 pack, and 1 4s3500 pack. I think 4s is better for larger outdoor tracks and 3s better for smaller indoor tracks.

When I get my Emaxx fixed (steering), I'll post actual tests and graphs between the batteries.

[RC-Monster Mike]

Thanks for the info. For a large outdoor track, I find that having some extra weight actually helps at times. I run the 2000mah, 15c discharge LiPos in my tc3 with a basic 4200 motor. I run two packs in parallel, so it weighs about as much as 5.5 nimh cells. I ma geared for mid 40mph and the acceleration is pretty insane. I don't have a data recorder, but I know I run 12-15 minutes and only put about 12-1400 mah back into the packs, so I think the draw is on the safe side. I planned on using the 3200s in my e-maxx and truggy conversion, as they need the amp draw ability. The 2000s will be used in the stampede and tc3. Hurry up and fix your steering! I am anxious to see the graphs for e-maxx duty!

[lipomax]

Do you have trouble with your diff on your TC? Mine keeps on getting loose and melting the plastic outdrives. So I got steel ones. Better, but after a few minutes, they slip again - at least it doesn't melt, but I have to almost lock them up between every battery pack! I' m thinking of running a spool in the rear now.

[lipomax]

I did try the basic 2100 motor the other day on 11.1 volts geared 28/72 x 2.5. It was okay for speed and acceleration - but when a motor spins too slow, you don't have as much fine motor speed control as you would if the motor was spinning a little faster. It seems like when a motor spins around 40,000 rpm it's easier to drive than a 20,000 rpm motor.

I'll have the emaxx tested by the end of next week. I'll start with the Feigao 10L with 22.2 volts comparing polyquest 3100 vs. Kokam 3200 vs. Kokam 2000. I'll have it geared 18/66 and use only first gear. That should give me a result of about 30mph in first gear. RPM should be right about 50,000 rpm. I'm gonna guess about 65 amp draws during acceleration... We'll see.

[RC-Monster Mike]

I had to go to the steel outdrives also and melted one diff. Once I rebuilt the melted diff and installed the steel outdrives, I haven't had any issues. I also run the front one way, so no diff to worry about there. I agree with your comments regarding rpms. 40000 is a nice number. It seems to be a happy spot for motor in terms of performance and running, and if you have too few rpms, the control becomes less smooth (half as many possible steps, I guess). I am looking forward to the e-maxx test results!

[lipomax]

Son of a gun... got the servo today, but more snow too!!! Sigh... BTW, can I order a servo saver for my emaxx for the JR servo? Do you have them in stock?