Have some LMT questions...

Originally Posted by jordan...

VWT4: how do you compare the performance of the Bigmaxx to the LMT 1950? Have you run either on 6s?

I run the BiGmaxximum in a 5kg Supermaxx and the Lehner 1950-7 in a 7kg LST2, so there are very diferent trucks..

Both with 5S lipos the SuperMaxx seems to be more powerfull but it's really 2kg lighter... The handling of the Pletty is smoother, maybe cause the 6 poles or the Schulze 18.149f controller, the motors stays always really cool.

I still have to test the BiGmaxx with the eagletree, but yesterday I got some info from the LST2: with 5S 20C lipos RPM were 36.000, 105A and 1600W, the motor ran pretty cool.


BTW Lehner recently opened an ebay shop: http://stores.ebay.de/LMTdirekt

[jordan...]

i just put some figures in for a BM running 51/20, does anyone know what rpm ranges the Bigmaxximums can run at happily? (the estimated rpms are around 50,000) Here are the results:

Enter Front/Rear Differential Gear Ratio (?): UE 1/8 scale
Enter Transmission Gear Ratio: E-maxx 2nd gear
Enter Spur Gear tooth count (?): 51
Enter Pinion Gear tooth count: 20
Enter total battery voltage: 22.2v
Enter kv rating of brushless motor: 2300 kv
Enter tire diameter in inches: 5.8

Total Motor Speed (?):51060 RPM
Theoretical Vehicle Speed (?): 60.65 mph (97.43 km/h)

jordan

[bdebde]

1) I would recommend a Neu 1515 2.5D for 6s. If going Lehner, a 1950/7 should be good. Stay around 40,000 rpm for whatever motor you choose.

2) The high amp version is the only way to go, the small plugs really suck on the standard models.

3) Don't get the cooling system, you will only suck dirt into the motor. The Lehners run plenty cool if set up properly (gearing,voltage).

4) I like the Neu's because made in USA (not concern for you in Aus), easier service. They are all excellent motors ( I have 1 or more of each), pick whichever you can get easily there.

As far as running the Big Maxximum on 6s, they can handle 75,000 rpm max, but I would not do it. I have run a Big Maxx on 6s in a 13 pound Muggy with a center diff (30K fluid) and it spent so much time on its lid that it was no fun. If you run that set up in a truck with a transmission instead of center diff, it would be even worse. I went to a Neu 1515 2.5 on 6s and am much happier because I can actually drive the truck instead of going to flip it back on it's tires all the time. The Big Maxx would be perfect on 5s, it is just too much on 6s.

Keep the RPM around 40,000 and you will have plenty of power. The Lehners make the most power and have best efficiency around there.

[jordan...]

so if the motor rpm's are found by multiplying the kv rating and the voltage, no matter what the gearing, the rpm's will not change?

hmm, that Bigmaxx does sound crazy...

[bdebde]

Originally Posted by jordan...

so if the motor rpm's are found by multiplying the kv rating and the voltage, no matter what the gearing, the rpm's will not change?

hmm, that Bigmaxx does sound crazy...

That is correct.

[jordan...]

thanks bdebde, really helped having advice from someone who has owned/run both the BM and a Neu motor whcih is comparable to a 1950/7 on 6s!!

Even though you said the BM is no fun on 6s, your statement has made me want one even more now now

jordan

[bdebde]

Yeah, I figure I can throw BM in my truck when I want to get nuts, and run the lower rpm Neu for general bashing.

[jordan...]

so would running a Neu 1515/1y at around 48,000 rpm be harmful to the motor?

[jordan...]

i've been doing a little more research into these motors, and found that the 22xx series motors can easily push a truck over 60 mph on 6s.

I was looking at a thread from a little while ago where i think Promod ran a 2240/10 on 18 cells and it was pushing 60.

Now i am a bit confused, because the 2240/10 has a 1480kv rating. This is pretty low (i think ), and i was wondering how this could still push 60? Is it just the larger size of the motor in general?

What Neu series would be the equivalent to the LMT 22xx series??

thanks in advance
jordan

[jhautz]

I can sum up the answer to your question in 3 words... Gearing, Gearing and Gearing.

You don't necessarily need high kv motors or high rpm to get high speed. Its all in the gearing. I broke 60mph in my buggy using a 1578kv Hacker 10XL motor and 5s. Thats only 29000 rpm for the motor.

l also did it with a Neu 1512/2.5d and 5s and a Quark 80B.

You don't need the biggest motor on the block to get high speeds. All the huge motors do IMO is suck your battery down faster. You can only get so much power to the ground with the grip generated by the tires.

Get a motor that runs a comfortable RPM on the voltage you plan to use and the rest is just a matter of gearing for the performance you want (within reaason). Many times I actually think the smaller motors feel more powerfull than the huge ones. They spin up faster and just feel more powerfull and responsive.

No need to kill a fly with a sledgehammer, and the 22xx motors are sledgehammers.

[jordan...]

thanks for the info on gearing jhautz, really helpful

does anyone know where I can get a LMT that doesn't deal in euro. So far i've only found 2 places which both deal in euro, and puts the price of a motor around 460-500 us dollars

i guess for that price i'm better off running a dual Neu setup

thanks
jordan

[bdebde]

Originally Posted by jordan...

thanks for the info on gearing jhautz, really helpful

does anyone know where I can get a LMT that doesn't deal in euro. So far i've only found 2 places which both deal in euro, and puts the price of a motor around 460-500 us dollars

i guess for that price i'm better off running a dual Neu setup

thanks
jordan

There is only one US dealer...FDM.

[jordan...]

thanks for the site bdebde, these motors are more in my price range! hmm... it looks like they have 'sledgehammers' in stock as well

[aqwut]

check out Lehners website.. they have excel sheets for almost all of their motors... shows you what Amp, RPM & Volts are most efficient...