9L Vs 9XL performance in Emaxx?
 

Hi, I was wondering what the sort of power difference is between the two motors on low voltages - 12/14 cells. I have both motors although the 9L is in a different car at the min, and figured the motors lighter and revs higher..so I can get a better top speed but will it have all the same crazy torque? To conclude, I'm happy with my 9XL performance, but was wondering if theres any advantage to be had with a 9L on 12 cells.

Cheers.

The 9xl would be the best bet because it would run way cooler than a 9L. You gear up on the 9xl for speed and still have torque due to the longer can. Pretty much just stick with the 9xl and ditch the idea on the 9l. A 9l would be good fora buggy, not a maxx.

Thats pretty much what I thought, thanks for confirming that, I'll leave the 9L in my RC10GT.

Only bit that bothers me is on 12 cells it has no real top speed, on 20/51 its around 25-30mph. Plenty of torque & accel, but I can't gear any higher. On higher voltages it has a much higher top speed, but for general mucking about I don't see the point in putting more cells than needed in.

Why dont they refer to 9L as a 540 9l / 9xl / 9L / 9turns / which one is cooler or hotter so confusing for the new folks like me, which one is better to run on 12 or 14 cells or wait maybe they r talking about the 1950 L who knows, I want to make a purchase but which one is going to give me longer runtime and which one is it ouch:007: :020:

Swift - I believe the 9xl will run cooler and give better run times, but on 12-14 cells, i owuld get the 7 or 8xl. But it depends on the batts.

I think there are a few reasons for the difference in L vs XL (or vs S for that matter):

1. Efficiency. There is an ideal rpm range where each motor is at its most efficient. To get that RPM, you apply the required voltage based on the kv value. Since an XL motor has a lower kv for a given turns count, you would need more voltage to get that ideal rpm. Running an XL with the same voltage as an L of the same turns won't be as efficient.
   
2. Weight. Well, of course the XL will weigh more, not to mention the battery weight for the higher voltage requirements.
   
3. Cogging: A lot depends on the controller firmware, but if you use a low kv motor on low voltage, it isn't going to spin very fast and the controller may have a harder time to read rotor position at low speed driving.
   
4. Power matching. For a relatively light (6-9lb) truck, you probably don't need tons of torque, so an L will suffice. Just like an S size works for 4-6lbs, and an XL works well for ~9 and up (to a limit of course).

That's my $0.02.

Thanks Brian and Neweuser this forum is great and always willing to help out,all you have to do is ask , I am kinda settled on a xl3600 or the 9xl with a 9920bk or MGM 16016 bought the bec and have the gp 3300 7cell already have the cvd and wish i had enough to get the g3,thanks for the info guys and this forums moderators make this a fun hobby. Still a project in progress. Yesterday I decided to put a 7cell gp3300 on my t4 wow with the ss5800 this thing was flying with no problems just a little warm on the motor but fun.:027:

Maybe I should just wait for the xxl thats new any suggestions

The XL3600 would fry the controller. Especially on 14 cells....My XL3100 ran hot on 12. Get the 8 or 9XL.

If you run like 12 cells. I would go 7xl. The 7xl can take more cells to if you choose.

swiftneed, the 7XL or 8XL on 12-14 cells will be very impresive. I run my 9XL on 14 cells now and love it.

Only thing that concerns me is the ESC gets pretty warm after a hard run with a 9XL, i'd hate to think how hot it'd get with a 7XL, without any forced cooling.

Just run a fan on it. I have run a 10xl and 9xl on 16 cells and did fine. If I were you, run the 9xl. you can gear it up and it'll stay cool. If you are sticking with just 12 cells, go with the 8xl. Then you could run 12 or 14 without problems...i always run a fan on the controller as extra insurance. They're not all that heavy, fairly cheap, and hell, why not?

Thanks guys I live in new york and the temp are now in the 60s definitely dont think the temp is going to be a problem I am leaning toward the 9xl but the esc has me concerned would like to get one, I dont want to buy two just one to hopefully later use on more cells currently 14cells.

So u guys r saying the fiego 540c 9xl for my emaxx how about the xl3600

Maybe this helps......

oK Squee gotcha:013:

Thanks for the info guys will order the quark monster pro , the ib4200 7cell and the 9xl getting them now

If you get the Quark, get some heat sinks for it...and maybe a fan

Kinda didnt want to add the fan but dont mind the heat sinks does mike sell them maybe i should go for the neu 1515 1.5y

The neu will definately run cooler and is more efficient. If you run the Quark....i would suggest a fan! I run two 30 mm, works great, never thermal. heat sinks you can find at computer stores and such. I created my own out of a block of aluminum. Mike can make them too, shoot him a PM. Search around on line to see what is close and cut it, then use arctic silver to mount the heatsink, once you have it to where you want it, you can thermal adhesive it, but i wouldn't recommend doing that until you are totally set after test runs as you won't be able to get the heatsink off!

OK here it goes quark monster pro,Neu 1515 1.5 , ib 4200 , and the ubec , NOW you know i will be asking questions after recieving items

run your cells in series...zoooom...zooom :)

Wise choice about the motor.. :)

So eager to purchase the motor didnt notice it says sorry this :010: motor is not in stock ok back to the drawing board any suggestions:032: :031:

OK check this out how about I get the monster pro, in the meantime use my hacker c50 and then instead get the G3 but i think there might be more stuff to buy like the motor stand :032: :007:

The 1512 2.5d is a good motor. It runs pretty good on a monster truck. I run mine on a 80b quark. I would suggest a 125 though.

would a difference in 700kv be substantial or is it just preference

I understand the i should get a lower kv motor for the torque because of the amount of weight

You want to match the kv rating to the voltage you are planning to run. Shoot for a total rpm in the neighborhood of 35,000 - 40,000rpm.

So...

the 2700kv motor would be a good 12 cell (or 4s lipo) motor,
12(cells) x 1.2(V/cell) x 2700(kv rating) =38,880rpm.

the 2200kv motor would be a good 14-16 cell (or 4-5s lipo) motor

the 1700kv would be good for 16+ cell (or 5-6s lipo) motor.

Geared properly, there shouldn't be much differance in top speed, but there will be in tourque.

Since it sounds like you are going for a 14 cell setup, I would think that the 2200kv motor would be ideal, and it would even leave a little room to add a cell or 2 in the future if you wanted.

1.5Y or 1.5D ?

I have the 1515 2.5D (1700kv) I think it's a nice motor too. I as going to get the 2200kv one but they were out of stock.

I like them in the 2000kv range... but depends on the vehicle and purpose. If I was doing a speed/bashing truck I would choose the 2200kv if not the 2700...

Seems like we are shooting for the 2000kv which is the 1512 2.5df neu i am wondering geared properly the amount of run time on ib 4200. Glassdoctor i meant the 1515 1yf i believe but luckily u guys r here for the help, I could see myself not matching up correctly what i would like, thanks so much for all the explanations thanks to jHautz for putting it in laymens terms, OH and by the way i let the smoke out on the shulze 18.61 experimenting on how to get this running the c50 was a rocket cool:007: :005: Squee did warn me :025:

OK finally after all this help just paid for the 1515 1yf and the quark pro125 I am in the cirlcle now:018:

Nice. :dft003: Should be a very solid, reliable setup.

I will recomend some sort of heat sink or fan on the quark though. Makes a HUGE diference.

Funny I feel the same way jhautz states cant decide if its more fun to make it or break it:005:

It's fun to build, and fun to wreck SOMETIMES, otherwise a tad costly! LOL

Here i am back on my build after a long :sleep:

3 year smoke huh lol

How goes the truck? 3 years is one heck of a bash session... :lol: